School of Life Sciences | Ask A Biologist

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You may know that your skin is made of cells, your bones are made of cells, and your blood is made of cells. But these cells aren't all the same types of cells. Different types of cells each do unique jobs in your body. Together, they let your body function as a whole. So to put it in a joke format, how many types of cells does it take so that an adult human can screw in a lightbulb? Any guesses? Over 200.

Question From: Mat
Grade Level: 7

Answered By: Jameson Gardner
Expert’s Title:
Graduate Student

More Information

Looking for the number of total cells in the human body? Visit Building Blocks of Life.

For more simplified information on cells, check out Cell Bits and Cell Parts Bits.
Interested in immune cells? Don't miss Viral Attack.


Have a different answer or more to add to this one? Send it to us.

Mixed cell image by Librepath.

One Wormy World

Around 4,000 years ago, on the wind-swept island of St. Kilda, Scotland, people started creating a food storage of sorts. They moved a population of sheep to the island, likely as a back-up food resource for when times were tough. Little did they know that their actions would affect 21st century science. Today, rather than ending up as a meal, sheep from this isolated population are the subjects of research on immune function. Evolutionary ecologist Andrea Graham takes Dr. Biology on a trip of exploration through the dangerous cliffs, windy conditions, and wormy world that the Soay sheep deal with on St. Kilda.

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Topic Time
Introduction 00:00
Why work on the Soay Sheep? 01:27
How did the sheep get on the island? 03:55
How does the body defend against a parasite? 05:15
Can up you get rid of round worms without treatment? 06:49
The difference between tolerance and resistance. 07:11
Do all the sheep have round worms? 08:26
Do you have to collect the specimen, or will a photo do? 05:18
How do the sheep get the worms? 08:29
How do you catch the sheep? 09:44
Unpacking a question from Andrea's website. 11:20
Autoimmune system, sheep, and Lupus. 13.52
Could our improvement in health and nutrition be a possible cause of some autoimmune diseases? 16:39
Where is the symbiotic part of your work? 18:27
Importance of bacteria in the gut. 19:16
What is next to discover or explore with the Soay sheep? 19:51
Let's talk about your background in art, science, and teaching in K-12. 20:33
Does your art enhance your science or vice versa? 22:44
Three questions - When did you first know you wanted to be a biologist or artist? 23:34
If you couldn't be a biologist or artist, what would you be? 24:38
What advice do you have for a budding biologist? 26:26
Sign-off. [learn more - Coping with Parasites in a Wild World] 27:25

Transcript - (PDF)

[wind blowing – sheep sounds in the background]

Dr. Biology:  This is "Ask A Biologist," a program about the living world, and I'm Dr. Biology. For our show today, we're going to be taking a virtual trip to the wind‑swept island of St. Kilda to learn about the Soay sheep. If you're not familiar with this island, it's off the coast of Scotland.

And, yes. I did say sheep. You can hear them in the background. To be precise, we're going to be talking about some nasty worms that live inside some of the sheep.

How they either resist or tolerate the worms is very important to their overall health and survival. My guest today is Andrea Graham, an associate professor of Ecology and Evolutionary Biology at Princeton University. She's at Arizona State University giving a talk at the Center for Evolution and Medicine about Antibodies, Health and Disease.

For our show today, we'll be talking about resistance and tolerance in the body, along with immuno‑parasitology.

I know, another word that just rolls off the tip of your tongue. But this one is simply a part of biology that deals with animal parasites in their hosts. In this instance, the worms are the parasites and the hosts are the sheep. Welcome to the show, Andrea Graham, and thank you for taking time to talk about your work with the Soay sheep.

Andrea Graham:  Thank You. It's a pleasure to be here.

Dr. Biology:  I guess the first question would be, why work on sheep, and why the sheep on St. Kilda?

Andrea:  Why work on sheep? It's true that we think of sheep as being domesticated animals. They give us wool. They give us milk. They are very widely cultivated in agriculture. But it turns out they might be really useful for developing our understanding of how hosts deal with infections, as well.

One major reason is that ‑‑ unlike the mice that are very frequently studied in immunology research, in understanding how we fight off infections ‑‑ sheep actually live quite a long time, in terms of how their life histories are designed. They start to approximate the lifespan of a human host certainly much more closely than a mouse does. Because a mouse, at best, lives only two years.

These sheep, some of them live up to 15 years and beyond. We think that sheep may actually provide a better view of the mechanisms of defense against infection, in a species in which preservation of life, extension of lifespan, is more central to the biology than it is for mice. Mice are really rigged for breeding.

They're really good at making more mice and they don't tend to live quite so long. So we think sheep are good in that way. We think that these sheep on the island of St. Kilda are especially interesting, because they have lived without human intervention for a really long time. They're unmanaged. They don't get vaccines. They don't get drugs to clear them of their infections.

They're doing it on their own. They also have a heavy burden. They're exposed to a lot of infectious agents and this is super important too. Not only are the sheep interesting enough themselves and doing it without the aid of medical intervention but people are observing them very closely.

I joined this study really quite recently, but others have been studying these sheep since 1985 making the most detailed observations you can imagine. We know everybody's birthday. We know everybody's date of death. It's a really quite extraordinarily detailed data set about the lives of these individuals and the worms they carry in their guts.

Dr. Biology:  Oh. We're going to get to the worms in just a bit. This is where the true gory parts come in but also the really good learning parts. St. Kilda, as I mentioned at the beginning of this show is an island, and I suppose that's good because these sheep are captive.

Andrea:  That's right.

Dr. Biology:  One of the questions I have is, how did they get on the island in the first place?

Andrea:  Yes. This is quite an amazing part of the story. About 4,000 years ago, during Neolithic times, people brought sheep out to this island as a backup food supply in case the fishing and such failed.

It is strange to think of sheep living out in the middle of the North Atlantic on this very tiny island, but there they have been for 4,000 years largely unperturbed by humans, although the early inhabitants did hunt them when the seabird egg crops failed, as it were.

But yes, it's a strange environment for sheep, but since they're captive on that island, we can actually reliably capture individuals repeatedly, and that is super important for watching how host parasite interactions change over the course of a lifetime.

Dr. Biology:  Right. Host parasites. These are those worms.

Andrea:  The parasites are the worms. They're the ones I think about the most.

Dr. Biology:  Right. So, these are the round worms?

Andrea:  Yes.

Dr. Biology:  All right. You also talk about infections. In Ask A Biologist, both the website and this podcast, we often talk about infections. You can get an infection from a cut. You can get an infection from catching of a flu virus or a cold virus.

There's also bacteria. In this case we're talking about something different. We're talking about a parasite. What are the relationships out of that, and how does the body defend against the parasite versus when I get a virus?

Andrea:  The key distinction I'd like to draw here is the sheer size of these parasites. Viruses are just vanishingly small. You can't see them without the aid of very fancy microscopes.

Worms on the other hand, can range in size to being meters long. Some of the tape worms that live in the gut are the most extraordinary in terms of their sheer size. You do not need a microscope to see that.

The worms that the sheep have are somewhere in between, but you definitely can see them with the naked eye. The key thing here is that they're living in the gut. They're living in the stomach, one of the many stomachs of sheep, and the challenge for the immune system is to push them out, basically push them toward the exit as it were.

Whereas if your sheep are fighting a virus infection, it's much more a case of either getting a cell to gobble up that virus, getting an antibody, or other molecule to bind to a virus and stopping it in its tracks. But those are too small.

The molecules and cells that are really good in clearing a virus infection, they can't get any traction on these big parasites. And instead, basically on the immune system, co‑opts the gut physiology, the one way traffic through the gut and pushes the worms out the other end. Mucus is a really big player in this.

The mucus that is used as part of normal digestion anyway, gets ramped up to a high level and shoves the worms out the door.

Dr. Biology:  Can you get rid of these roundworms on your own if you don't have any kind of treatment?

Andrea:  Yes, some hosts do. They have the right genes to help them get that purging done. But most, domesticated sheep need a lot of help with it. Certainly drugs that help paralyze the worms and make them easier to shift out of the gut, are incredibly important to agriculture.

Dr. Biology:  There are a couple words I used earlier on, and there's a difference between the two of them. But, they're still both very important to our health and basically any animal health like in the case of our sheep. That's the difference between tolerance and resistance. Can we talk about those two words?

Andrea:  Yes, of course. Resistance is a word that biologists use to talk about the ability of a host to kill the virus, kill the bacteria, kill the worm, or get it out of there. This whole purging mechanism that I was talking about is a resistance mechanism, because it reduces the number of parasites in your body.

Tolerance on the other hand, is a way of letting them be, letting them stay in the body, but maintaining your health despite their continued presence. We're just starting to understand what some of those mechanisms might be. But we are starting to think they're at least as important as resistance mechanisms in promoting health.

Dr. Biology:  Right, because there's a certain amount of energy required to push them out or to get rid of them, verses if you can just cope with them in your body?

Andrea:  And get on with growing, and living, and breeding, all these priorities animals have. We think that maybe just as important as clearing parasites.

Dr. Biology:  Do all the sheep have the worms?

Andrea:  Very high fraction of them do. The prevalence is often as high as 80 or 90 percent. 80 or 90 percent of the sheep, especially when they're lambs the young are very full of worms. The percentages drop off in adulthood and that's because the sheep's immune systems learn how to resist the parasites.

Dr. Biology:  How do the sheep get the worms in the first place?

Andrea:  That's important. It's transmitted by feeding on the wrong bit of grass basically. If the sheep are foraging for their dinners in the greenery on the ground, and if there are nematode larvae, young worms attached to that grass, they will ingest the parasites along with their food.

Then the parasites, from their point of view, they undergo some development in the gut. They partner up with another worm, they make some babies and that gets passed out in the feces. So that everything's happening in the intestinal tract and it gets passed out with the poop of the sheep.

Once the poops on the pasture, those little larvae can come out again and get ready to infect the next host. It's what we call a fecal‑oral transmission, because it depends upon ingestion of another host's excreta.

Dr. Biology:  OK, we will not be eating grass.

Andrea:  No, don't eat grass.

Dr. Biology:  All right, you had these sheep on the island and you have a bunch of scientist there studying them. How do you catch the sheep?

Andrea:  That is tricky I must say, because we can't use sheepdogs even if the National Trust for Scotland would allow it. We couldn't do it because these sheep do not act like the sheep that sheepdogs are used to. When someone approaches these sheep, instead of flocking together and being herdable, they bolt in every direction, and they're bolting on a bunch of sea cliffs, and over Neolithic Ruins. It's really rough terrain, and they're of course nimbly running around.

All these scientists who spend most of the year in the lab, behind the computer, whatever they're doing, are trying to run around. There have been broken ankles, I myself lost all the skin on my left knee, falling, tumbling about. But, what we end up doing, with a lot of clumsiness along the way, is herding them into traps.

Basically, we herd them into gaps in the walls of the old settlement there. There are gaps in the walls into which we install hemp fencing, and we herd them in there and then quickly close the gate. Then we're able to herd them with tarps and things into a corner of that. But, only once we get them in a confined space by just chasing them through gaps is pretty low tech and pretty hard on one's joints.

Dr. Biology:  We need a video of that. I bet that could be put to some comical music.

Andrea:  Yes, absolutely. In fact, sometimes people make these videos inevitably. There's some great tumbling fall that one of the scientists takes right in front of the camera. Yes, there actually is good footage of this.

Dr. Biology:  I visited your website, and I found a page that I really like. It highlights what scientists do. What I'm saying is, scientists ask questions. They seek answers. These are the how and why type of questions we all have, and I say we all have at least when we're young. When we're young, we're full of wonder, and everything's fun to explore.

You listed five clear questions on your website. I don't always see this in every lab website. The number one question is, why are hosts, here we'll talk about our sheep, prone to producing overzealous, and really like to do a lot of responses that cost proteins, and then we're going to have to talk a little bit about proteins, and may actually even cause disease? That's a really big question.

Andrea:  It is a big question.

Dr. Biology:  Let's unpack that and let's talk about it.

Andrea:  I'd be delighted. That is my favorite question. That's why I put it at the top of my list. You're right. It's multi‑layered. It's really getting at trying to understand why immune systems harm their bearers and trying to understand the genetic and environmental causes of that.

In particular, it defies our expectations about organisms in a natural environment, because we think that every bit of food that you eat that you could convert into growing stronger, so that you win the next wrestling match. If you are mounting an immune response, you often have to direct that calorie or the proteins that you eat into the immune response. Instead, you have to invest in it.

It's to the detriment of other stuff you want to do, like grow. There are many other priorities in life, but immune responses can detract from all those other priorities. What on earth are hosts in natural populations, who are very often food‑limited? They're hungry. The sheep, for example. They almost never have enough to eat, especially at times of high density of sheep on the island.

What are they doing investing so strongly in immune responses, when it comes at this cost to the rest of what they might like to do? That's one part. Then, there's the other part. Like, the vertebrate immune system is supposed to be the pinnacle of adaptive evolution, this wonderful machine that can achieve things like remembering a flu virus for decades.

All these great examples of the wonderful things is the immune system can do, but it also can blast holes in the host's own tissue. I just find that a great puzzle. I want to understand that.

Dr. Biology:  In other words, it can turn on itself.

Andrea:  Correct. That's what I mean.

Dr. Biology:  That'll get us into some of the things you've been doing with the autoimmune diseases. Some people know about some of the arthritises that are autoimmune, but you are spending time with a particular one called lupus.

Andrea:  That's one of the ones I think about a lot.

Dr. Biology:  Let's talk a little bit about what lupus is, and then how these sheep are going to relate to lupus. Because a lot of people when we think about research, it's not always really clear what we're doing out in the middle of an island in a really cold windy spot researching these sheep that are wild. What's the link?

Andrea:  The easiest way to explain the link is that, lupus is an antibody‑caused disease. What happens is these molecules that are so powerful in defense against infection, if you have too many of them or they start clumping together or binding self too avidly, they can cause harm especially to kidneys. Host kidneys end up being smashed up by antibody.

What we've done in the sheep is to ask whether the propensity to make that kind of disaster unfold is a natural thing at all, or if it's something about the relatively artificial environments in which modern people live where we don't have very many worms. We are not food‑limited.

Have we alleviated the nutritional cost of immunity, such that we can invest in these very crazy, strong immune responses that might do more harm than good? We looked for the evidence that any of this kind of this autoimmune condition existed at all in the sheep. When we found it, we went on. That was finding a) it is out there in a population that's full of parasites and often food‑limited.

It does seem to be some sort of natural phenomenon. What became more interesting is when we went on to study how it might be associated with survival of the sheep. We found that the sheep who were potentially prone to that kind of disease manifestation, they actually had a survival advantage. We've been busily trying to unravel that.

Because if stopping short of when the actual kidney damage starts happening, if hosts experience benefits of having that kind of strong immune response or even self‑reactive immune responses, we need to know that, if we want to understand why lupus and lupus‑like conditions might persist in human populations. It gives us a test bed for the occurrence and causes of this kind of predisposition.

Dr. Biology:  In the case of lupus, if left unchecked, it starts to attack tissues in the body and organs. In this case, you're talking about the kidneys. What's interesting is if I read this correctly or if I understand you correctly is that, the body, when it has nothing better to do, because it doesn't have to worry about these other things.

Now, it's got extra time on its hand, extra energy on its hand, does it start to turn on itself? Is that the way I'm reading it?

Andrea:  Yes. I would say we need to ask and answer those questions. There's a little more to it. That is that, parasites often immunosuppress the host. If you think about it, that would be to the worm's advantage, if we return to the worm example. A worm who can turn down the immune system of the host is a worm who's going to live longer itself, and who is going to be able to lay more eggs.

We expect that to be very much in the best interest of the worm. If that also dampens the chances that the host will overreact to its own tissues, that it will have collateral damage to its own tissues, then having worms can also bring us benefits. That's why we would expect that in parasite‑poor environments, we would expect more of these kinds of excessive immune reactions.

Dr. Biology:  I read something when I was looking into your work. You said this area of science that you're spending time in, it enables you to, jointly pursue interest in symbiosis. Also, the parasite ecology in medicine.

Let's talk a little bit about that, because we have been talking about parasites. That's a one‑way street. That's where the parasite benefits and the host doesn't. Often, the host either gets weak or dies.

Andrea:  Yup.

Dr. Biology:  In a symbiotic relationship, there you have two organisms that are benefiting from each other.

Andrea:  We would call that even a mutualism, where there's mutual benefit.

Dr. Biology:  In your work, where is the symbiotic part?

Andrea:  Symbiosis means living together. Ecologists would say that even the host‑parasite interactions are on the symbiotic spectrum, because it's organisms living together. You're very right to draw the distinction between a parasitic relationship and a mutualistic relationship.

Everything you can point at in, say what we think about human health and interactions with the microbes in our guts through to the most horrible, nasty pathogens like Ebola that sweep through human populations will fit somewhere on the spectrum between their benefiting to our clear detriment in the case of parasites or where our normal physiology depends upon their presence, as in the case of a mutualism.

I think modern medicine is starting to realize that a perfectly clean gut ‑ let's keep talking about the gut because the data are best there. A perfectly clean gut is a terrible thing for a host to have.

Dr. Biology:  This comes up, because we think of bacteria as something very bad and it's clear that we have very beneficial and critical bacteria in our gut. We have more bacteria in our body than we have cells?

Andrea:  Correct.

Dr. Biology:  Without these particular bacteria, we wouldn't be living, quite frankly?

Andrea:  Correct. That's right.

Dr. Biology:  What's next on your list of things to do and things to find out about the Soay sheep?

Andrea:  I would say my number one, what's next, is figuring out the tolerance variation among them. What did we pick up on, when we saw that some of them were able to maintain their body weight in the face of a very heavy worm burden and others lose body weight in the face of that same parasite burden? What are we picking up on there? We don't know.

We don't know how they might be achieving that, the ones that don't lose much body weight. They might be the lucky ones. They were exposed to some subset of the parasites that are out there that just happened to be kinder. We don't know if it's on the parasite side or the host side or both and I'd love to know.

Dr. Biology:  One of the fun things about having guests on Ask‑a‑Biologist is that I get to go out and explore what you've been doing and how you got to where you are. You earned your undergraduate degree in biology and sculpture?

Andrea:  Correct.

Dr. Biology:  After that you taught both of those subjects at New York City in the public high schools. Can you talk a bit about your journey in biology and the arts?

Andrea:  Sure. One thing I like to say is that, producing both of my final projects for that dual degree enabled me to do the other. Each one enabled me to do the other, because I feel that the scientific thinking and the scientific writing, exercises one part of my brain really well. But it lets other parts wither.

So, I was delighted that when I had writers block or reached some sort of dead‑end in the science project, I would go into the welding studio and make progress on my final project, for my sculpture degree, which was a throne. I made a throne out of found parts of Model‑Ts and tractors and that sort of thing.

Dr. Biology:  Do you still sculpt?

Andrea:  Not as much as I wish I did. Being an oxyacetylene welder is not exactly a portable hobby. It's a difficult thing to take with you and I've traveled to many places. I'm very lucky to have been based in lots of places for my work and I haven't managed to bring the welding kit with me, but I ought to.

I do keep up my artistic side in other ways, but not my sculpture and that is my favorite. I really do miss it. But then I was even luckier I think, to take it into the high school setting, where it was really experiential learning high school.

What I did was I took students out into the city in small groups to either investigate scientific questions and many of them had to do with human behavior. These were teenagers and human behavior is one of their favorite things to think about, hypothesize about. We would study human behavior, for example on the subway system or I would take them into the city to do found objects sculpture.

We would rummage in the city and come up with objects that would be the basis for our next sculpture project. So experiential learning and really engaging the students in the city that way, was absolutely wonderful. I feel lucky about that.

Dr. Biology:  You mentioned that the benefit, for you with the art and science, is you got to exercise both sides of your brain. Does your art background enhance your science career or possibly the reverse, where your science career enhances your art?

Andrea:  I would say it enhances my science. I think that after college I got better at thinking across both sides of my brain, even about scientific questions. I don't always think about problems in the same way other people have thought about problems. I think that's a real strength. I think that has helped me as a scientist.

I also think that it's part of why I think it's important to have a handsome website or maybe I also bring aesthetics to my science communication and I'm glad about that. But I think I'm maximizing the potential crosstalk between these two parts of my interests.

Dr. Biology:  This leads me into my three questions, I ask my scientists. So we'll jump in. When did you first know you wanted to be a biologist and in your case maybe first knew you wanted to be an artist?

Andrea:  I would say that I just completely love being out of doors, poking around creeks and puddles. I grew up in Colorado. I spent a lot of time in the mountains and the life form that I remember getting most excited about really early on was lichen. I just thought lichen was amazing and maybe that's even partly why I was drawn to studying symbioses.

I couldn't believe it was this amazing collaboration that led to these beautiful lichens all over the rocks. As for when I first wanted to be an artist, I was a tinkerer with found objects from the start as well. Maybe both of them arise from being very curious about the world around me and trying to think about it in new ways and maybe assemble new things out of what I collected.

Dr. Biology:  Now, I'm going to take it all away. You can't be a scientist. I'm going to take away your art.

Andrea:  OK.

Dr. Biology:  And I know you like to teach. So I have to do the trifecta for you.

Andrea:  Oh dear. OK.

Dr. Biology:  The reason I'm doing this is I want you to stretch. If you couldn't do any of those, what would you do or what would you be, if you could do any of those. I mean, if you could do anything?

Andrea:  Anything but those three. I think that's a pretty straightforward answer, because I love languages. I think that if I couldn't do any of those things I would want to be, I don't know if linguist is quite the right word, but I'm fascinated by shared word roots across languages and then the extent to which some languages have really weird, out of left field roots to their words.

I guess maybe I'm cheating because in a way it's another evolutionary problem. I'm basically saying if you're not allowing me to study evolutionary biology, I might study evolution of languages. So maybe I'm cheating but nonetheless I think I'd want to study languages. Learn more of them, get better at them. I have a few second languages that are extremely poor and rusty and I would love to be able to have them flow more.

Dr. Biology:  What are the languages that you have?

Andrea:  French is my best second language but I've also studied Hindi and Japanese. Hindi, I have used to good effect and so I know it could be resuscitated in my brain if I only used it more. Japanese, I have never visited Japan. I've helped a couple of tourists who knew even less English than I knew Japanese. I was able to use it, but basically not very much.

The thing I like about those languages is they're ostensibly rather different from each other, except that Hindi does come from the Indo‑European language group. So it's not surprising that there are commonalities there.

Dr. Biology:  For our final question. What advice would you have for a young biologist or perhaps someone who wants to move into the world of biology from their current job?

Andrea:  I think I would give the three word advice. Go for it. I think biology is a really, fascinating, fundamental science, but I think people are really appreciating, it is the wave of the future. It has not been as amenable to our analytical methods as physics and chemistry so far. It brings layer upon layer of complexity. We need all sorts of brains working on it to really figure it out.

It's also incredibly important to not only our health in the context of my own work but in terms of food security and climate. Just about every major challenge we face today, there's a biological element. We need all our best brains on the task.

Dr. Biology:  Well, I'm biased of course. I would have to agree with you. Well, Andrea Graham, thank you for visiting with me today.

Andrea:  Been my great pleasure. Thank you.

Dr. Biology:  You've been listening to Ask‑A‑Biologist and my guest has been Andrea Graham, an Associate Professor of Ecology and Evolutionary Biology at Princeton University. If you'd like to explore more about the Soay sheep and Andrea's research, we have a story in our PLOSable section.

It's called, "Coping with Parasites in a Wild World." It's written by one of Andrea's colleagues, Adam Hayward. There is also an added bonus to the story. Like all our PLOSable stories it's linked to a primary research paper published in one of the PLOS journals. You can think of it is a fun way to get started reading articles written by scientists.

The address is,‑wild‑world. Don't worry if you couldn't write that down. We're going to have the link from the podcast page. You can also learn about the Soay sheep project at That's actually spelled S‑O‑A‑Y S‑H‑E‑E‑P.

The Ask‑A‑Biologist podcast is produced on the campus of Arizona State University and is recorded in the Grassroots Studio, housed in the School of Life Sciences which is an academic unit of the College of Liberal Arts and Sciences.

Remember, even though our program is not broadcast live, you can still send us your questions about biology using our companion website. The address is or you can just Google the words “Ask A Biologist”. I'm Dr. Biology.

Transcription by CastingWords

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One Wormy World

Audio editor: CJ Kazilek


The race is on. It is one where biologists and citizen scientists are working as quickly as possible to find and identify all the species on Earth before some go extinct. It might not seem like an important race, but we learn from entomologist Kelly Miller that not knowing what species we are losing might be more important than we think. Today scientists combine traditional and newer computer tools to speed up the search. These combined tools are part of the world of cybertaxonomy.

Content Info | Transcript

MP3 download | 15MB

You are missing some Flash content that should appear here! Perhaps your browser cannot display it, or maybe it did not initialize correctly.

Topic Time
Introduction 00:00
What is taxonomy and why is it important? 01:30
How many species have we discovered and ordered? 02:06
Why is is important to discover and catalogue species before they go extinct? 02:55
Mining species - for drugs [Nature's Medicine] 03:31
Citizen Scientist 03:59
What do you need to do when collecting a specimens? 04:40
Do you have to collect the specimen, or will a photo do? 05:18
What do you do after you collect a specimen? [make your own plant press] 06:07
How do species get their names? 06:57
Why names are so important. [Planet Bob Video] 07:51
Cybertaxonomy 08.22
Using GPS to mark the location where specimens were collected. 09:11
Using Google Earth to enter GPS information. 10:20
Other tools for taxonomy. 10:43
Expeditions - collecting insects. 11:16
Do you have to travel to far away places to find new species? 12:14
Do you have a favorite expedition? [lion story] 13:00
What insects do you collect and study? 14:11
Scanning photography - a new tool for entomologists. 17:02
Why are illustrations important if we can take photographs? 18:26
Part of discovering a new species is you get to give them a name. 19:43
Back to cybertaxonomy. 21:50
What would the museum of the future look like? 23:12
Spida-web - the future of cybertaxonomy 25:03
Three questions 26:06
When did you know you wanted to be a biologist? 26:15
What would you do if you could not be biologist/entomologist? 27:53
What advice do you have for someone who wants to become a biologist? 29:16
Sign-off. [learn more - Linnaeus & Taxonomy - Making the List] 30:59

Transcript - (PDF)

[beeps – electronic lock and vault door opening]

Dr. Biology:  This episode of "Ask A Biologist," is being pulled from our special collections, that have been stored in our secret vault.

This is Ask A Biologist, a program about the living world and I'm Dr. Biology. There is a race on today. You may not know it and it's one that's critical, not only for humans but also for all living things on this planet. Like many races, it's a race against time and the growing list of living things becoming extinct.

Leading the race is a group of scientists and citizens scientists who are searching our planet to find undiscovered species to organize them and name them. This is all part of the world of taxonomy.

Now people have been discovering, classifying, and naming species for thousands for years. More recently with the invention of computers and the development of the Web taxonomy is moving into the cyber world.

My guest scientist is Kelly Miller, professor in the Department of Biology at the University of New Mexico. He's here to talk about the world of taxonomy and the new frontier, cyber taxonomy. What is it, and how will it change the way we see and learn about species that live on this planet?

Welcome to the show, Kelly, and thank you very much for visiting with me.

Kelly Miller:  Good to be here. Thank you very much for having me.

Dr. Biology:  All right. Before we jump into the world of cyber taxonomy let's first talk about taxonomy. I mentioned it briefly at the beginning of the show, but let's do it justice and talk more about it. Why is it important?

Kelly:  Well, it's important because the study of taxonomy is the study of the diversity of living things. With thousands and thousands, in fact probably millions, of species of living things, that's one of the most amazing scientific endeavors that human have ever undertaken, is to better understand the diversity of living things, the things that live around us every day.

Dr. Biology:  Let's put some numbers on this. How many species do we know? We've given them names, and we've started ordering them.

Kelly:  Right now it looks like we have about 1.7 million species.

Dr. Biology:  OK, we'll round that up to two million species. How many do we think we are missing?

Kelly:  We think we're probably missing on the order of 15 million species.

Dr. Biology:  Whoa. Lots of work to do.

Kelly:  That's a lot of work to do.

Dr. Biology:  When I talk about the race against time, every day we're losing species.

Kelly:  That's right. Because of things like deforestation, habitat change, climate change, and things like that, our earth is changing. As a result of that many species are going extinct, many of which we don't even know yet. Species that we don't even know about are going extinct every day.

Dr. Biology:  This has been going on before humans were even thinking about taxonomy. Why is important to find them? I mean they go extinct. They're missing. What we don't know, we didn't have. Who cares, right?

Kelly:  Well, some might argue that. I would argue the exact opposite. Those things that we don't know about, that's the thing that enriches us and helps us to better understand the world around us.

When they're gone, they're gone forever. That means that knowledge is gone forever. That means that the possible uses of new species to humanity is gone forever. That knowledge will be gone forever if we don't go and try to understand it now.

Dr. Biology:  Right. Some of this mining if species and in particular, some of the drug companies been doing this for quite some time, right?

Kelly:  That's absolutely right. Many of the drugs that we get are found in plants. What's interesting about that, now I study insects and insects are chemical factories.

There's so many chemicals involved in insects that we don't know anything about. And we haven't exploited those for pharmaceuticals and other sorts of medicines yet. We've only done it with plants. We haven't even started looking at insects yet.

Dr. Biology:  To be fair, I'm on your side. I'm very interested in knowing about what's out there before we lose it. I mentioned that there is a group of scientists, taxonomists, but they're also citizen scientist, right?

Kelly:  You bet.

Dr. Biology:  As a citizen scientist what can I do to help in this endeavor?

Kelly:  One of the things that can be done is simply collecting the specimens that are there. It's something that I started when I was just a kid, I started collecting insect specimens. That's how I got interested them.

Those insect specimens, if you combine the specimen with information about where you collected it and when you collected it, that becomes a valuable data point for scientists to use down the road.

Dr. Biology:  If you're taxonomist or a citizen scientist, what are the things you need to write down and catalog?

Kelly:  Well, the most important thing is the place where you collected it. We know that insects, for example, occur all over the world, but certain species only occur in certain places and you need that information to better understand the distribution of those species.

You also need to know the date that you collected it, as many people know, some insects come out certain times of the year and you have to have that information. That's true of plants, that's true of fungi and that's true of all living things. So it's primarily the place that you collected it and the date that was collected.

Dr. Biology:  Now, when you collect, do you always have to have the thing or can you get by with a photograph?

Kelly:  Well, in my opinion you have to have the thing. A photograph is nice for hanging on the wall and for recording your adventure, but the thing is what goes into museum collections and that's what's there for all time. We have specimens and collections that were collected by Darwin.

Now, if he had only taken photographs of those specimens, we wouldn't have the actual specimens. We wouldn't know exactly what he was looking at because now we can go to the actual specimen and identify it.

Dr. Biology:  Right. And you don't know what view you might need to look at and so if they only took a view of, in the case where you work with beetles, the top of the beetle...

Kelly:  That's a good point.

Dr. Biology:  ...and not the bottom then there'd be all sorts of problems. All right. So, we go out there. We collect the specimen. What do we do next?

Kelly:  There are certain techniques you need to use depending on what kind of thing you're collecting. With insects, certain insects need to be collected into alcohol to preserve for all time. Other insects need to be collected, so they can be pinned. If you're collecting plants, they need to be pressed, so that they can be put on herbarium sheets and preserved in museums.

So, there's a variety of different techniques. If you want to learn more about how to collect a particular species of living things, there are a lot of resources available on the Internet, for example.

Dr. Biology:  We actually have a really nice section on, Ask A Biologist, that actually shows people how to make their own herbarium and it's a great way to start a collection.

Kelly:  Now, that's great.

Dr. Biology:  We've collected these specimens in various ways. Whenever I look in a book they always have a name. Who names them?

Kelly:  Well, that's the job of the taxonomist.

Dr. Biology:  OK. And what's the big deal about naming specimens?

Kelly:  Well, what's so big a deal about naming people? Could you imagine if your family didn't have names? What's the first thing when you bring a dog home, a puppy home, you need to give it a name. You need something to call it. You need a handle so that you can communicate about it.

Dr. Biology:  But there is more to the name other than just communicating. When we give it a name or when taxonomists are doing it, were actually naming them in order to organize them?

Kelly:  That's exactly right. We have an organization system for the names that we use. That organization system ensures a number of different things. For example, we want only one name for every species of living things on the planet. That's critical, otherwise we wouldn't be able to communicate effectively.

Dr. Biology:  So one scientific name, very precise. OK. It's an interesting thing because we have a really fun little video that was produced out of the International Institute for Species Exploration and it's called Planet Bob. And the reason I like it is, it's not just so much the fact about giving a name. In this case, everything is named Bob.

That's the same problem if it didn't have any name. In this case, everybody and everything is named Bob and it is pretty comical. So, let's talk about cyber taxonomy.

Kelly:  OK.

Dr. Biology:  How computers and computer networks, i.e. the Internet are changing taxonomy? What's going on? What's the Brave New World?

Kelly:  Well, one of the most exciting things about cyber taxonomy is, no longer does taxonomy have to be restricted to just scientists. Now, anyone who can access the Internet has the possibility of going online and finding out what the different species are.

Back in the old days, it used to be just scientific journals and stodgy old museum guys who were able to do this kind of work and understand the diversity of life. Now anyone can go online and access information about the diversity of life, about taxonomy from anywhere.

Dr. Biology:  So, more people can get involved and one of the things you mentioned was, making sure you write down the location of where you collected the specimen and that used to be, maybe just a map and a reference of a town or something. But that can be a problem because town's names change and there are other issues because you might need to be more precise.

The new smartphones and mobile devices now have GPS, Global Positioning Systems in there. So I have heard and you can tell me more about this, that you can use those now to tag where you collect the specimen?

Kelly:  Well, that's absolutely right. In fact, that's exactly what we do. All of the specimens that we collect now have latitude and longitude that we get from a Global Positioning System and that's included with the information associated with that specimen. That allows us to do very sophisticated things like digital mapping of the distribution of species.

So you can see every place on the world where the species occurs by mapping it, using latitude and longitude information from that label data that's included on the specimen.

Dr. Biology:  Does this require a special software or we hop on the Web and go to Google Earth.

Kelly:  You can absolutely go to Google Earth. That's the easiest way to get that information out there. We have a number of projects where we are labeling all of our specimens with latitude, longitude, getting them into a database that Google Earth can access and you can see the distribution of species, just with a simple click of your mouse.

Dr. Biology:  Are there other tools out there that we're going to be able to use or are using right now, that are making a big difference on taxonomy and world cyber taxonomy?

Kelly:  Well, one thing that I hope is in our future is the ability to download an application onto your phone that will allow you to identify specimens while you're in the field.

Wouldn't that be fantastic if you could download some sort of an identification tool for the butterfly that you're looking at right now while you're in the field? That's something that I do think is in the future.

Dr. Biology:  Wow! That would be cool.

Kelly:  Yeah.

Dr. Biology:  So, I went out and did some research on you. I went to your website and one of the things I loved about it, you had the classic areas, publications and the lab and the things you're dealing with, research was a topic.

We had one section there called expeditions and I like just the word alone. And I saw that you've been, jeez! You've traveled to so many countries, Central and South America, Africa, Australia. It sounds like a really pretty cool life?

Kelly:  Well, you know it's cool. It's fun to see these exotic locations, but it can also be very difficult. A lot of these places we go don't have the kind of roads we have. They don't have the kind of food that we have and it can be a real challenge getting into these areas. Especially when our goal is to collect insects in some of the most remote areas on the planet, which is where many of the unknown species occur.

Dr. Biology:  So this isn't for the simple tourist?

Kelly:  No, not for the faint of heart.

Dr. Biology:  [laughs] All right. But do you really have to go to the far ends of the earth to discover new species? Could I go out to my backyard and find something?

Kelly:  You absolutely could. We know so little about things like insects, that there is new species being discovered literally in our backyard every day. In fact, just to give you an example. You guys have all heard of field crickets, the little black crickets that live outside your house. Well, it turns out that the species that lives right in Phoenix has never been described.

Dr. Biology:  You're kidding.

Kelly:  No, I'm not kidding.

Dr. Biology:  Wow!

Kelly:  Never been described. In fact, from all of the Western United States, only six species have been described. Now we have as many as 50 new species from the Western United States.

Dr. Biology:  That's pretty cool. Sounds like a neat project to me. How about, if we are talking about your expeditions, do you have a favorite one?

Kelly:  A favorite expedition. Boy, they're all so great. But there is one that, I think, really blew my mind and that was a trip I took to Africa, the country of Namibia. And what was so great about that expedition was, not only were we collecting a lot of fantastic new insects, but we also got to see all of the big African animals. We saw elephants and rhinos and lions and every kind of big animal that you could think of over there.

Just to give you an example of one story. We were camping actually in the bush one night and we woke up in the morning. We were sleeping in tents and I heard off in the distance, a lion roaring. And then, pretty soon I heard a roaring a little closer. And then after a little while it roared a little closer.

Dr. Biology:  [laughs]

Kelly:  And he kept getting closer and closer. And finally we'd had enough and we decided to get into the pickup trucks that we were driving. We sat in there and the lions roared within 40 yards of us on the other side of some bushes.

Dr. Biology:  OK. I'm in the trucks with you.


Dr. Biology:  Let's talk a little bit about when you're on these expeditions what are you actually looking for? Because obviously you don't hunt for every species out there. You have some favorite ones. So what's your favorite one?

Kelly:  That's right. The groups that I work on are mostly water beetles. We study beetles primarily that live in the water. And the group that I work on right now has about 6,000 species described. But we find new species on every expedition that we go on.

Dr. Biology:  What's the name for these water beetles that you like?

Kelly:  The main ones are diving beetles and whirligig beetles.

Dr. Biology:  Whirligig beetles. I love that name alone, whirligig. Those are the ones that, if I'm not mistaken, if you look at a pond or a little pool of water, it looks like there are these little almost ripples going around and if you actually look, instead of being something dropped on, there's a little beetle in there...

Kelly:  That's right.

Dr. Biology: that little ripple. They also are pretty unusual. They're not your normal‑looking insect. If you could say that insects are normal‑looking?

Kelly:  That's right. They're pretty unusual and they're very uniquely adapted for living right on the water's surface. That's pretty atypical. What you find though is that if you look really close at the beetle, you'll see that one of the adaptations they have is, their eyes are divided.

Now, most insects have one pair of eyes like we do, but whirligig beetles actually have two pairs of eyes. One pair looks up into the air, the other pair looks down into the water, and that's pretty unique to beetles.

Dr. Biology:  Now, that's almost like having eyes in the back of your head.

Kelly:  [laughs] Yeah. That's exactly right. It's exactly like it is.

Dr. Biology:  That makes me wonder, how do you think they see it? I mean do they have a split screen? I mean, how you're going to process both of those? Do they turn one on and one off and why do they have two pairs of eyes?

Kelly:  That's a really good question. I think the best answer to that is, they probably see everywhere all of the time and so they're processing all that information, all at once. I don't think they turn anything off. But they look up and they look down, because as with most insects, they need to worry about getting eaten by birds and other predators. So they're looking up for birds, but they're also looking down for fish.

Dr. Biology:  Fish. So how big are these whirligigs?

Kelly:  Most of them are pretty small. They might only be about a quarter of an inch long, but then there are some that are over an inch long.

Dr. Biology:  But that means pretty small fish?

Kelly:  Well, pretty small fish, yeah. Sure.

Dr. Biology:  When something is that small, how do you get a good look at it. I mean you can obviously grab a microscope, I suppose. But how do you look at it in real detail?

Kelly:  Well, I'm afraid that the best way to do it is through a microscope. Sometimes, we use different kinds of microscopes, including electron microscopes to look very close at the small details. Because it's in those details where species are different from one another.

Dr. Biology:  Recently, I had some students, some co‑hosts. Ask A Biologist has student co‑hosts. They spend a lot of time in the W. M. Keck bio‑imaging lab, which is really just down the hall from us and they were exploring the microscopic world, or as I like to say traveling into inner space as Micronauts. [laughs]

Everybody is excited about astronauts, but inner space has got some amazing things and worlds to explore. You also spend a lot of time imaging your insects using a very cool instrument built by Visionary Digital?

Kelly:  That's right.

Dr. Biology:  We think you can collect a series of images, it's like get a stack of cards, each card and each one of those is nice and sharp, because of anybody's ever looked through a microscope, some things are in focus and some things aren't. If you readjust, you can get the stuff that was blurry in focus.

This lets you get all the things sharp and then you take it to the computer and it puts it back together in unbelievable detail. How important is this new tool to cyber taxonomy and to your work?

Kelly:  It's absolutely incredible. Even though we talked about at the beginning that a picture isn't substituted for a specimen, pictures are critical for communicating information about those specimens. The opportunity to take high‑quality digital images and make those available on the Internet has revolutionized taxonomy and identification work.

Dr. Biology:  You also showed me illustrations today that are based on the photographs. The big question for me is if we get all this detail and we can do this wonderful imaging with this instrument, why are we still drawing them?

Kelly:  Well, have you ever used field guides to identify birds?

Dr. Biology:  Some people have and I have, yes.

Kelly:  Sure. There's some field guides use drawings of birds and other field guides use pictures of birds and sometimes one of the field guides is a little better for a particular bird than the other type of field guide. And that's true when it comes to identifying parts of insects as well.

Sometimes, a particular thing is communicated better using a drawing. Other times, it's communicated better using a photograph.

Dr. Biology:  In this case, maybe simplifying what you're looking at with the drawing, makes it easier to understand the overall structure, and the way that insect looks, whereas the photograph has just got so much detail, you might not catch all that information?

Kelly:  That's exactly how it works here.

Dr. Biology:  All right. So part of discovering new species is giving them names and you actually have quite a history with this. Yes, he is rolling his eye.

Kelly:  [laughs]

Dr. Biology:  I'm saying this because you've come up with some rather exotic and actually well‑known names. Can you give me a couple?

Kelly:  I have. I need to say that, I've done this in large part, in collaboration with Dr. Quentin Wheeler and I blame him for much of it. But we've named some species after some famous people. One of the great things about discovering new species is that, when you find a new one, you get to name it. You get to give it a name and that name stays for all time.

It's a great opportunity for us. We have given a number of species some prominent names. We named a species after Steve Colbert. We also named a species after Roy Orbison, the great singer and probably the most famous one is, we named a species after George Bush.

Dr. Biology:  Oh, really.

Kelly:  We did, we named the species after President Bush, while he was President and believe it or not, he actually gave us a call to thank us for naming that species.

Dr. Biology:  Now, which George Bush are we talking about?

Kelly:  George W. Bush.

Dr. Biology:  So give me that name of that species.

Kelly:  The name of that species was Agathidium bushi.

Dr. Biology:  OK. And what was the actual insect?

Kelly:  It's a type of beetle that lives on a group of organisms called slime‑mold.

Dr. Biology:  OK [laughs] . Well, I was going to ask and I suppose, I'll go ahead. Do you make sure you match the species characteristics for the person it's named after?

Kelly:  [laughs] . No, I'm afraid that's not quite what we go for.

Dr. Biology:  [laughs] OK.

Kelly:  I need to say that any time we name the species after a person, it's considered an honor. In fact, it's considered poor form to name a species to dishonor somebody. And in fact, there are species that I've named for my wife, for my daughter, and for my son. Also, for certain friends. But we also name species for a variety of other reasons.

Sometimes, we'll name a species after the place where it was collected. Sometimes, we'll name a species after a particular feature that's really different on the species.

Dr. Biology:  Getting back to cyber taxonomy. Most collections are housed in natural history museums and similar museums. It may be housed at universities around the world. In that case, you've got to be able to get the physical collection to see the specimen in most cases. How is cyber taxonomy changing the natural history museum?

Kelly:  It is revolutionizing, how we use natural history museums. Back in the old days, you had to borrow specimens or go visit the museum just in order to see the specimens in that museum. Nowadays, with the digital imagery, we can put images of all the specimens in the collection online. So you don't necessarily have to go to the museum or borrow specimens.

The other possibility that, I think, is really exciting, is the idea of having a virtual microscope. Perhaps, you could look from your desktop computer, through a microscope that exists at a museum somewhere and look at specimens in that museum through their microscope. That's one of the most exciting things, I think, about cyber taxonomy.

Dr. Biology:  Right. So you wouldn't have to rely on how someone took a picture, you'd actually be able to get the specimen, maybe even move it around.

Kelly:  Maybe even move around, maybe even do a dissection of that specimen.

Dr. Biology:  That'd be pretty cool. We're getting into the next question and the next question is, all right. I'm going to let you build the Natural History Museum of the future, using cyber taxonomy. What would be your dream museum?

Kelly:  Well, of course, the specimens are still really important, so we would have the specimens still residing in the museum. But all of those specimens would have the label information digitized so that you could access it from anywhere in the world and would also have images of all of the specimens available from multiple different angles.

In that way you could access that collection from anywhere in the world, anytime you needed to and get all the information that was available there.

Dr. Biology:  Now, assuming you going to throw that microscope in there or a tool that could go out grab a specimen, and bring it over, put it under the microscope, let's you look at it...

Kelly:  Now, that's a great idea.

Dr. Biology:  So, now we have these robots at this giant room. I can see robots going and grabbing specimens, depending on who needs what. What about some hunting for a specimen, if you're not an expert? You know your water beetles like the back of your hand, which you probably had them on and so for you it's not that difficult, and you also speak the language because there are terms and words we use that the average citizen scientist may not have.

What are we going to do about that? Is it already out there? Can you go some place, if I know nothing about water beetles and I find one and I want to know what it is, that I could track down, what it is?

Kelly:  Well, there's a few resources like that, but that's just getting started. That's something that we need to develop as a community, as taxonomists is, those resources online for people to access. You've all used Wikipedia. I can imagine a taxonomic Wikipedia, where all of that information was available.

Dr. Biology:  We had Norman Platnick on the show and he had spider web, which was a really cool tool and that's one when where you could actually go take a picture of a spider, upload it and the computer would actually go out and try to find a match. That is intriguing to me. Do you think that's going to be in somewhere in the future of cyber taxonomy?

Kelly:  I absolutely do think it will. You guys have all heard of face‑recognition technology, where you take a picture and you match it up against faces in a database. The same exact sort of thing could be used for taxonomy or for identification. Take a picture of a specimen, match it against a database and hopefully come up with an identification.

Dr. Biology:  So in this case, everybody could be a taxonomist?

Kelly:  Well, everyone may be able to identify specimens, but keep in mind, it takes a lot of knowledge to identify new species and what are the new species and to categorize them and catalog them.

Dr. Biology:  OK. So then everyone can be helpful for a taxonomist?

Kelly:  Absolutely, anyone can be helpful.

Dr. Biology:  Because you could go out there, plug in a new water beetle that you found. It goes through this fancy database. It doesn't find anything and says, "Uh, this might be and I can say might be a new species." At that point give you instructions and how to mail it too, maybe off to your laboratory.

Kelly:  I think that would be fantastic if we had something like that available.

Dr. Biology:  OK. So, we can get people involved, because if I remember at the beginning we're short species by at least 15 million?

Kelly:  That's right.

Dr. Biology:  And if we don't get involved, all of us, we're going to have some problems?

Kelly:  That's right. All of that information will be something we'll never know about.

Dr. Biology:  And it can be in your backyard. You don't have to travel off to exotic places. Although, if you have the money, the time and the desire, maybe you could do that too.

Kelly:  And you're not afraid of lions.

Dr. Biology:  [laughs] And you're not afraid of lions. One of the things we do on this show, none of scientist gets out of here without answering three questions. All right, the first one is an easy one. When did you first know you wanted to be a scientist or a biologist? Was there that spark?

Kelly:  Well, I would have to say was, when I was so young, I can't even remember exactly when it was. As far as I know, as long as I've ever been alive. I wanted to be a scientist.

Dr. Biology:  Now, did you always know you're going to be a taxonomist and that you're going to be working with water beetles?

Kelly:  No, I didn't know that. That came quite a bit later. But once I found out that there were people in the world that got paid to identify new species, describe them and name them, I knew that's exactly what I wanted to be.

Dr. Biology:  Right. So did you think of yourself and do you think of yourself as an explorer?

Kelly:  Absolutely. My whole life, I wanted to be an explorer. Once I found out that most of the places on the earth had already been explored, but then I found taxonomy and I found new species. That's the cutting edge of exploration. And that sense of discovery is very fulfilling.

Dr. Biology:  Right. I always say, especially the taxonomist that go out and do these wonderful expeditions, I really do see the Fedora, the Indiana Jones hat or the Indiana Jane hat, depending on if you're a male or female. It is really, I think a cool job. If you want to do it, that's probably one of the best you could do.

Kelly:  Absolutely.

Dr. Biology:  OK. Now a little more challenging. If you were not a scientist or a biologist, what would you be? And because my scientists have a tendency to say, Well, I'd love to be teaching, because we also teach. I take that away now. I love both of them.

Kelly:  OK. That was going to be my answer.

Dr. Biology:  Yeah. [laughs]

Kelly:  If I wasn't a scientist, I don't know what I would be. Well, I'll be honest with you, I think one of my great loves in life is woodworking and I think I could be a carpenter or a cabinet maker or a woodworker. I think that's the type of thing that I would probably be.

Dr. Biology:  It doesn't surprise me. I mean, again it's working with this form and shape and there's some really beautiful pieces of furniture, and objects that are made.

Kelly:  Well, it's similar to taxonomy too. You take something that's unordered and disorganized and you organize it into something that's beautiful.

Dr. Biology:  All right. And the last one, all right. What advice would you have for a young scientist, maybe someone that just got turned on to taxonomy? What's your advice for them?

Kelly:  My advice is go for it and contact the experts. Most of us are really excited to help you out, to encourage you, to give you resources if you want to try to identify things. And you should contact us. Don't be afraid just because we're scientists somewhere. We're just people just like you and contact us and let us know what your interests are and how we can help?

Dr. Biology:  Well. And if you're trying to say ID, a water beetle, Ask A Biologist, of course, has the ask section and now that we have Professor Miller here. He is on the hook. He has now become an honorary member of the team and so maybe we'll get him the images and move him along there. Or if you live in Albuquerque, right.

Kelly:  Yep.

Dr. Biology:  You could do that or if you just want to give him a call you can actually find him on the Web.

Kelly:  Absolutely.

Dr. Biology:  Professor Miller, I want to thank you very much for visiting with me today.

Kelly:  It's been my pleasure. Thank you very much for having me.

Dr. Biology:  You've been listening to Ask A Biologist, and my guest has been Professor Kelly Miller, visiting ASU from the Department of Biology at the University of New Mexico.

The Ask A Biologist's podcast is produced on the campus of Arizona State University, and is recorded in the Grassroots Studio housed in the School of Life Sciences, which is a division of the College of Liberal Arts and Sciences.

And always remember, even though our program is not broadcast live, you can still send us your questions about biology using our companion website. The address is or you can just Google the words Ask A Biologist. I'm Dr. Biology.

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Audio editor: CJ Kazilek

Time Traveling Paleoentomologist

If you could travel back in time what would you find 50 million years ago? What was the climate like? Would you find the same plants? What animals were crawling, walking, and flying around? Paleoentomologist Bruce Archibald takes Dr. Biology back in time to explore the planet during the Eocene Epoch where things were a bit different than today – there was even a giant flying ant that would make anyone look twice.

Content Info | Transcript

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Topic Time
Introduction 00:00
What is biodiversity? 01:46
Do you have a time machine? 02:55
What is a fossil? 03:18
How are fossils made? 04:08
What makes a good fossil? 05:24
How much detail or resolution can a fossil have? 06:23
Why are museum fossil collections important? 08:24
The giant ant story. [ Titanomyrma lubei ] 11:34
What did the ant look like? 13:23
How does an ant get from Germany to North America? 14:15
Another research project on climate and biodiversity. 18.02
How the research was carried out. 21:45
Three questions. 25:24
When did you first know you wanted to be a biologist? 25:37
What would you be or do if you were not a paleoentomologist? 28:02
Advice for someone wanting to be a biologist. 29:28
Sign-off. [ Read more about Giant Insects. ] 30:42

Transcript - (PDF)

Dr. Biology:  This is "Ask a Biologist," a program about the living world, and I'm Dr. Biology. Today we have the opportunity to do some time traveling. In this case we're traveling back in time, and not just for a short trip. We're going to be going back as far as 50 million years.

What's the occasion for the journey? Well, my guest has been exploring the world around 50 million years ago. He's been learning about insects living at that time. Oh, and by the way, scientists call that period of time the Eocene Epoch.

While he's been back there, what's he been doing? He's been studying tiny insects. Some of which are smaller than the nail on your little finger. He also has an interesting story about a giant insect. Well, giant by our standards. You might be asking how large? Well, how about an ant that's five centimeters long, which is about two inches, or using our hand analogy the size of an adult thumb. Along with his work with insects, he's been studying the climate these animals lived in and their diversity. In other words, how many different kinds of species of insects lived during the Eocene Epic?

My guest today is Bruce Archibald. He's a paleoentomologist in the Department of Biological Sciences at Simon Fraser University. In case paleoentomology is new to you, paleo means old or ancient and entomology is the study of insects. So Bruce spends his time studying ancient insects and the world they lived in.

Today we learn how this paleoentomologist travels back in time and what he's discovered. Welcome to "Ask A Biologist" Bruce Archibald and thank you for taking the time to visit with me.

Bruce Archibald:  Thank you Dr. Biology.

Dr. Biology:  Let's get started with just a couple words just so that we have some of our vocabulary down. First is biodiversity and the reason I bring it up is you hear it a lot. But I think it's good to know a little bit more of what we're saying. So what is biodiversity and why do biologists talk so much about it?

Bruce:  Wow, well there's a lot of different ways of defining it. I'm looking at it in terms of species richness in a community and that is how many species are you packing together. But there's a lot of different ways that people define biodiversity depending on the kinds of questions they're asking. Species richness in a community is sort of the thumbnail sketch of how I'm looking at it.

Dr. Biology:  Right, so it's not just the number of species but the number of different kinds of species.

Bruce:  Mm‑hmm.

Dr. Biology:  Comes up because if we talk about the tropics, it's not uncommon for them to say it's a very rich environment. It's very biodiverse. Then if you move further north you end up with less biodiversity.

Bruce:  Absolutely, yup.

Dr. Biology:  That's part of the reason that that term gets used. I agree that that's not necessarily the only reason. The other thing is I talked about us traveling back in time, but I want to be really more accurate. Do you have a time machine?

Bruce:  Well, I've got the fossil record.

Dr. Biology:  Exactly. You do get to go back in time by studying those fossils.

Bruce:  You bet. Yeah.

Dr. Biology:  That's the next best thing to a time machine.

Bruce:  Absolutely.

Dr. Biology:  And in some cases, maybe even easier because they don't run away, right?

Bruce:  That's right. [laughs] They don't.

Dr. Biology:  Let's talk a little bit about what is a fossil and how are they made.

Bruce:  Fossils, the way I define them and look at them, are the remains of animals and plants or fungi. Anything that was living, or their works that are found from a long time ago.

Now, their works might mean their track ways or the nest of a bee that might be found as a fossil. Or if you find a fossil leaf and it's all torn up from chewing marks, that might tell you a lot about the insects that were feeding there at that time . The fossil's not only the leaf but the fossil is the trace of the behavior left behind by those insects, as well.

The word fossil can cover a wide range of things which tell you about life in the past.

Dr. Biology:  And how they're made. How do fossils get made?

Bruce:  There are a lot of different ways in which fossils are made. For example, a lot of the fossils that I look at, they were in a forest surrounding a lake. The leaves and the insects maybe blew out or flew out and landed on the surface. Then floated for a short while on the surface tension. Then sank down through the water column to the mud below.

Each year a little bit more of this dust‑like mud would settle over them. And eventually the lake basin fills up with sediment. Then that gets compressed and that mud squished and turned into stone. That's one way that fossils are made.

Fossils can also be made in other environments, in a marine and oceanic setting or in amber for example, which is the resin of trees. They get stuck in there like a sticky trap and covered over by the resin. Then that winds up in maybe a coal swamp where the trees get turned into coal.

There's a lot of different ways in which life can be preserved from the past. Like I say track ways, for example. Walking along the muddy river bank. That muddy river bank is filled in with sediment and then exposed millions of years later.

Dr. Biology:  What makes a good fossil?

Bruce:  Well, once again, it depends on the questions you want to ask. A good fossil leaf for a paleobotonist might be very complete and whole. A good fossil leaf for someone who studies insect behavior might be one that's all eaten up. That would be a good one for that person.

For me, I look at insects body fossils, that is the actual body insects themselves. What I want to see is something that's clearly preserved so that I can see the minute details is as complete as possible. Lot of fossils are mushed up, to use the scientific term, or incomplete because of the way the rocks split or whatever.

You often need to see a lot of the structures, defined structures to understand what that insect was. So, a good fossil for me has got enough for me to really tell who it was and what it's related to today.

Dr. Biology:  That's brings me to a really great point. That's how much detail can be captured in a fossil. Let's go back to basically something that's stone. We won't do the amber. What kind of resolution can you get compared to film or a really good digital camera?

Bruce:  You can get amazingly good fossil insects. In fact, modern entomologists are often shocked when I show them some of the fossils of insects because they can't understand how good these can be. I can get tiny wasps that are maybe four to five millimeters long in which I can look down to the wings and see the tiny hairs on the wing membranes.

Dr. Biology:  Would it rival film?

Bruce:  Yeah, some of the insects that I'm looking at is really limited by the lenses in the microscopes. There's more detail there than I can see with the gear that I've got to look at them.

Dr. Biology:  So optically, we can even get to the level of resolution that fossils have?

Bruce:  You bet, and gear will get better and better, and we will be able to know more and more. That's why we put these things away in drawers and maybe in a hundred years time someone has some super space age equipment and to be able to do a lot more than I could do with them today.

Dr. Biology:  Ah, the future paleobotanist or...


Dr. Biology:  ...the paleoentomologist.

Bruce:  That's right.

Dr. Biology:  This is actually a fun topic because a lot of people have seen fossils. They've seen amber on, for example Jurassic Park as a classic where they see the amber.

Bruce:  Yes, absolutely.

Dr. Biology:  Then stone, it's not unusual to go out to a trade shows and other places where people actually sell them as pieces of art. There are actually beautiful pieces out there. The other place you see them, as you mentioned in the drawers, tucked away in the natural history museums.

A lot of times you don't even get to see them because maybe they're not the pristine beautiful piece the whole specimen that you get to see, but they have a lot of information in them. What I'm curious about is, why are museum fossil collection so important?

Bruce:  Oh, wow! Well, they're super important. For example, there's not that many people who look at fossil insects like myself. Some of these fossils sites their a lot more paleobotanists if you look at the fossil plants. Paleobotanists will go to a site and collect these leaves and other plant material. And then they'll see, "Oh, there's much insects here. Well, I'll just taken them aside in the box."

Those going on a museum collection, they might sit there for 50 years or 80 years or a hundred years until the right pair of eyes come along and sees them. As long as the're safely and carefully stored in the museum with the right database, somebody will come along one of these days and say, "Ah, I know what that is." I'm able to work on that.

Dr. Biology:  I find that really interesting, because I think some of your work, you've even gone back to some early collections that they gather just much information at that time, and then you've revisited it.

Bruce:  Absolutely.

Dr. Biology:  It reiterates the fact that it's not always that we're changing the answers or what we know. We're just getting better tools to understand better what we have in front of us.

Bruce:  That's right. Sometime we do change the answers because we have better equipment to ask the questions more finely. Of course, in science, everything is the best knowledge we've got at that time. Best answers we have available. Sometimes, we can get better answers either by theoretical of answers., people understood things better, or sometimes just the equipment. It gets better.

Back in Galileo's time, he could see a certain amount with his telescopes but now we've got the Hubble, and our answers are more precise. We could do more stuff.

Dr. Biology:  We were just talking about microscopes as well. Robert Hook and Anton Van Leeuwenhuek. It was interesting because because that's a fun story in itself. You could see then, you could see cells, but you couldn't see inside cells. Now, we've got new, you can get into the organelles. Within the organelles, you can get into the DNA, and it goes on and on. All with better instruments.

Bruce:  I should just interject this here for a second. We were talking about mosquitoes, and amber, and the whole "Jurassic Park" thing. That actually happened in a certain sense. But now, I'm talking about a shale fossil, fossil in rock.

That was a friend of mine. Dale Greenwalt, who works at the Smithsonian, was looking at shales about the same age as I'm looking at in British Columbia, a little bit younger. In Montana, he found mosquitoes there. Those shales are, I believe, about 47 million years old.

He is a geochemist, so he was able to look at these fossil mosquitoes and do some analysis and find the iron compound in this mosquito's gut was a blood meal. He was able to do that and get to that level to see this ancient mosquito's last meal.

Dr. Biology:  Wow. Let's go back to our museums.

Bruce:  Yes.

Dr. Biology:  Turns out that not uncommon that you go and visit other museums and look at their collections.

Bruce:  Sure.

Dr. Biology:  We're going to talk about one of your finds, and that is by today's standards, a giant ant.

Bruce:  [laughs] Yeah. You bet it was giant.

Dr. Biology:  It's not like, there's a 1954 movie called "Them," where it's these giants ants. I mean, they're...

Bruce:  The size of a tank or something.

Dr. Biology:  Yeah, size of a tank. These aren't like that, but it's still an amazing find. There's really is an interesting story with these ants. Can we talk a little bit about them?

Bruce:  As you mentioned, I found this specimen in a museum drawer. I was visiting Denver Museum on Nature and Science. I don't know it's formal name, Culture, Nature and Science or something.

The paleobotanist there, Kirk Johnson at that time. He said, "Yeah, we got this great, big fossil insect. We want you to take a look at it," and I, "That sounds pretty good." I went down and I looked at it. I immediately knew, "Oh, I know what this is." It was one of these giant ants.

I knew it because they had been found in Germany. They were pretty famous from Germany. There had been a wing of a ant related to that found from North America, but it was a smaller one. It was a small relative, but none of these giant ones before. The wings are also known from Britain, I believe, from the UK.

Anyway, I saw this and I thought, "Oh my God. OK. Here are these ants have come over from Germany at some point, or which way we don't know. From here to Germany, or from Germany to here." I recognized this ant right off the bat.

Dr. Biology:  Yet, tell me a little bit about what the ant would look like today...

Bruce:  Sure.

Dr. Biology:  ...if you got to see it.

Bruce:  In fact, if you took a little bird, and you plucked its feathers, and set it next to this ant, this ant would be size of that little wren or maybe a little chubbier. The queen ants have wings. They're flying ants. Flying along, they would have been very impressive.

I named this ant "Titanomyrma lubei." The name lubei was named after Mr. Lube, finder of the fossil. But, Titanomyrma was a fun name. "Myrma" just means ant, and "Titano" means titan of the ants.

I found out recently that it was actually used in a video game. But in that game, they show the ant as being the size of a dog, which it's fun.

Dr. Biology:  We're talking 50 million years ago. If we think about today, how does an ant get from Germany to North America today? It's different than what could've happened back 50...

Bruce:  You bet. I should just mention also that I found it in a drawer of a Denver museum, but it was unearthed in Wyoming. That was where the fossil was found. Once again, it was roughly 50 million or so years ago. That turned out to be a very interesting story about how the distribution changes of animals and plants.

At that time, that's called the Eocene Epoch, is the name of that time, the early part of the Eocene Epoch, the North America and Europe was connected by land. I'm sure your listeners may be aware that continents move by tectonic forces, there's continental drift. The Atlantic Ocean has been opening up. Europe and North America are moving away from each other.

That's a good fun fact. If you take your thumbs and put them so that the pointy ends of your thumbs are apart from each other, the two thumbnails are growing away from each other at about the same rate that Europe and North America are separating from each other. Ain't that a good fun fact?

Dr. Biology:  Yeah.

Bruce:  [laughs] Anyway, back then, 50 million years ago, Europe and North America were still connected. But, they were connected through Greenland. You could walk from here in Arizona all the way to Spain, or whatever, through forest all without getting your feet wet.

There was this also a time when there was low sea level around the world for a bunch of other geologic reasons. You had low sea level. The continents closer together formed these land bridges. Actually, that didn't last long, geologically speaking. It was an interval of time when we had this connection available both through the closest of the continents and the lowered sea level.

Dr. Biology:  But we have a tendency, when we think of time these days, we think seconds, minutes, years. In this case, it's how long for this land bridge?

Bruce:  Oh boy, honest, it could have been 10 million years of so. An instant in time. [laughs]

Dr. Biology:  Geologic time.

Bruce:  That's right, paleontologically speaking. Like I say, forest across of the Arctic, and probably forest right up to the Arctic Ocean at that time. There was no ice sheets or harsh winters at that time.

There was all of these plants and animals able to extend their ranges across the pole and make a common range between Europe and North America at that time. A lot of things that we see today, kinds of trees or those sorts of things, which are uncommon between the continents may have at that time expanded their ranges in that way.

It was still temperate. Things that lived in hotter climates would have found it difficult to cross that northern land bridge, because the climate may have been similar to that of say, I don't know, Portland, Oregon today or so. If you like to live in a tropical climate like Brazil, you might find it hard to migrate through an area that has the climate like Portland.

This big ant tells a pretty interesting story about how plants and animals are arranged between the continents today. The different kinds with different climate tolerances may be arranged between the continents.

Dr. Biology:  All right. Let's switch gears just a bit. You have another project. It's also with fossils. It's again around the same period of time, about 50 million years ago. It has to deal with seasons, temperatures, and biodiversity. Can you tell me a little bit about what you've learned?

Bruce:  What I looked at in the project that I did is I looked at climate and how climate might affect biodiversity as it changes from the topics into the temperate zone into higher latitudes.

As you mentioned, there's two climatic factors that really differ. One is the amount of sunlight and heat. There is greater in the tropics. The other is that it has very low temperature difference between summer and winter.

If you're down in Costa Rica for example, the average yearly temperature is maybe about 26 degrees, 25, 26 degrees. That's really hot. It's hot there all year round.

Dr. Biology:  In Fahrenheit, that's around 78 degrees.

Bruce:  All right. Your coldest month average temperature is only about a degree below that. Your warmest month, a degree above that. Your fluctuation from the coldest to your warmest month is only a couple of degrees.

Dr. Biology:  Even in Fahrenheit, that's what, 75 to 79 or something like that.

Bruce:  It's not a whole lot.

Dr. Biology:  No.

Bruce:  But, you get up into the temperate zone here, you're going to have these wild fluctuations. Maybe 28, 30 degrees or so centigrade.

Dr. Biology:  Forty‑eight degrees, I can tell you right now when you do that.

Bruce:  [laughs]

Dr. Biology:  If you do 20 degrees, you're going to be around 68 degrees Fahrenheit. Then, how cold maybe?

Bruce:  It depends on where you are in the Northern hemisphere, but you might get the coldest month mean temperature about minus seven or so.

Dr. Biology:  Right, that's 19 degrees Fahrenheit.

Bruce:  OK. You need a coat, you definitely do. By mean temperature in that coldest month, the average temperature each day can be colder or hotter. You can have drop down to pretty cold days within that cold month.

Dr. Biology:  Certainly below freezing.

Bruce:  You bet. The point is this that we have this wild fluctuation between summer and winter. It gets stronger and stronger as you move from the equator away into the north or to the south.

Both of these things change. As you mentioned, the variables. The heat and light coming in is one variable. How does that affect biodiversity? Or, as temperature seasonality increases as your biodiversity drops. Is that the cause?

Now, there's various explanations. For example, the heat and light hypothesis, idea might be that you have this luxuriant growth, so you have big populations. You can have big populations of things that would be rare. That allows for lots of different species to live together. There's one explanation.

Or, the seasonality explanation might be that when you get into northern areas, you have this wide range between summer and winter. You want more generalists. You want fewer kinds of things, but those things that are there can live in lots of different types of environment.

That means less species, even if you've got lots of individuals less species together. Those are the types of explanations people have. It's really hard to separate. It's really hard to figure out which might be the case.

We go to the ancient world where we may be able to find an answers and break this logjam and find a way of examining this. That's what I did for this project. I sampled insects in Costa Rica, in a lowland tropical jungle today. I sample insects is Massachusetts, in a temperate zone forest by a lake, and these are modern insects.

Then I sampled fossil insect community in British Columbia, Canada. This fossil community lived at a time in a upland, in this cool upland, where the average yearly temperature is about the same as Seattle today, or Portland, or Vancouver.

But the seasonality was extremely low. Very, very mild winters. You maybe didn't need a sweater. Of course that doesn't mean much sitting here in Arizona to say you didn't need a sweater, but if you have average temperature like Vancouver to say, "You didn't need a sweater in the winter," that's saying something.

What I wanted to know is, was the biodiversity of these insects like it is today in the temperate zone? The common factor would be the coolness of the fossil site and the modern temperate zone. Or, was the biodiversity high like it is in the modern tropics? Then the common factor would be the low seasonality. The fact that the summer and the winter are pretty different.

It was by having this third sample site that I could try and understand which of these two variables is associated with change and biodiversity.

Dr. Biology:  The answer?

Bruce:  To make a long story short, this is a big, long project.

Dr. Biology:  How many years did you spend on this?

Bruce:  That was about seven years, I think.

Dr. Biology:  I just want people to realize that you just didn't go out. It was something over night.

Bruce:  I had to collect massive amounts of insects in all of these places. I'd assigned them all to species level and work them up. It was a very fun project, but it was also a long time. That's science. [laughs]

What you're getting at the answer here is that the biodiversity in this temperate, coolish upland of ancient British Columbia was similar to that of a modern lowland tropical rain forest.

Dr. Biology:  There were a lot of different kinds of species.

Bruce:  It was tremendous numbers of species packed into these communities. This indicates this change in biodiversity we see across the globe today maybe associated more with stability, temperature seasonality, than with the heat and light of the tropics.

Dr. Biology:  The wider the swing between hot and cold in a particular location is going to have an impact on the number of species that you'll be able to have in that location.

Bruce:  That's right. How it is that living things respond to this forcing factor, this triggering mechanism? We don't yet know why it might be that seasonality could affect diversity in that way. That's another project for one of your listeners to go to grad school and figure out. Seriously, there's a lot of interesting projects out there still undone. That's one of them.

Also, I love to do everything twice. By that, I mean we want to do something then confirm it with another angle. Not only did I take the insect samples and specimens, but also leaf samples.

Working with a paleobotanist, Dr. David Greenwood out of Brandon, Manitoba. For part of this project, we looked at the broad‑leaf tree diversity and found that that actually was more similar to the tropical parts of Queensland, Australia than it is to Massachusetts. This was the second confirming aspect of this study. We looked at plants as well.

Dr. Biology:  I love the fact that you left something for the future paleobotanist or paleoentomologist to do.

Bruce:  [laughs] Yes.

Dr. Biology:  That leads me into a part of the show that I love doing with all my scientists. We have three questions.

Bruce:  OK. You have not prepped me on this.

Dr. Biology:  I never prep my scientists.

Bruce:  [laughs]

Dr. Biology:  I want you to think on your feet. The first one is, when did you first know you wanted to be a biologist, or if you all ready knew you're going to be an entomologist or paleoentomologist. What was the "aha" moment?

Bruce:  I certainly liked these things when I was little. I was very interested in insects, animals and plants, but in a general way. I didn't have this particular liking for one over the other. I was very fortunate in having parents who read books to me when I was really little about nature and the natural world. That was a really good thing.

When I was a little kid, I liked to watch nature shows, and that kind of stuff. I liked to get out in the woods. But, I put that in the background until I was older, until I was grown up. Then I started to become more and more interested by reading books on fossils. I decided to go out looking for fossils near where I lived in Vancouver.

Sure enough, I found a variety of fossil insects. I thought,"These are really great." I thought, "Maybe there's got to be a lot of things you could tell from these." I took them around to local universities.

I was very much encouraged by the people there. They said, "Well, maybe this is something you should follow up on." It was very nice to get that encouragement, because I didn't believe I could do it.

Part of it was realizing that there was very little known about these fossil insects, and that there was big opportunity there to do the work and to figure out new things. That was one of the things that surprised me getting into science all together.

I thought pretty well everything was known, or a lot more was known. The more I got into it, the more I realized that we're still in the golden age of discovery. That there is a lot of great fundamental questions out there to approach and to try and work on. That is not going to go away anytime soon.

Dr. Biology:  How old were you when you went out on your first fossil digs or hunt?

Bruce:  Well, I was grown‑up. Let's see. I might have been like 40 years old.

Dr. Biology:  You came back to it definitely later on.

Bruce:  I came back to it as a grown‑up, absolutely. I spent many years away from it. There were a lot of people saying, "Oh, you can't do that." But, they were wrong.


Dr. Biology:  I'm glad you decided to come back and do it. But now, I'm going to take it all away.

Bruce:  OK.

Dr. Biology:  You can't be a biologist, and so all the forms of being a biologist. Most of my biologists love to teach, so I'm going to take the teaching away just so you can't slide into that. This is where you get to stretch. If you could do anything, what would you be? What would you do?

Bruce:  Wow, I'd love to be a cook. I don't know that I would be that good at it, but you could always try. I think to me, cooking is about the most creative thing that you can do and has this immediacy because you eat it up and it's gone.

People who are really good cooks amaze me, because they can go into a fridge and just see what's there. They turn out something wonderful, because they've got that ability to put it together in that creative mind. I admire that.

Dr. Biology:  It's an important point. I think scientists that are creative are also the most successful.

Bruce:  It shares the aspect that what you really need, I think, to be a good scientist is the same. That is the ability to see the connection between things that other people might think are unrelated.

You see one thing over here, and one thing over there, and you think, "Ah. What if we combine them," or, "Oh. What if we use that technique?" It's the ability to make those connections.

Dr. Biology:  The last question. This is a perfect one for you.

Bruce:  [laughs] All right.

Dr. Biology:  The reason why is you came to your current career later in life, right?

Bruce:  Mm‑hmm, yeah.

Dr. Biology:  I always ask, what advice would you have for our future biologists, or paleontologists, or entomologists. In your case, someone maybe who's been doing it as a hobby. They did it when they are younger. Now they think, "I'd like to do that for my..."

Bruce:  Full‑time.

Dr. Biology:  Yeah.

Bruce:  What advice would I give? The advice that I would give is do the thing that excites you the most. The reason I say that is because going to university is a lot of hard work. If you enjoy it, if you like it, if you're excited by your goal, you won't mind that.

You'll find that hard work also pretty fun, because you're flexing your muscles. It's like going to the gym, but you've got to put in that effort. If you're not really excited, it's not going to work. You're not going to have that gasoline within you to make you go. My advice would be to pick what really excites you, what really makes you excited to do.

Dr. Biology:  Bruce Archibald, thank you very much for visiting with me today.

Bruce:  Thank you, Dr. Biology. It's been a pleasure.

Dr. Biology:  You've been listening to Ask a Biologist. My guest has been Bruce Archibald, paleoentomologist in the Department of Biological Sciences at Simon Fraser University. Bruce has been here visiting ASU to give a talk at our new natural history collections facility.

If you want to learn more about giant insects, journey on over to our story on prehistoric insects called "Big, Big Bugs." This is where you'll get to learn about insects that lived over 300 million years ago. The address to the story is pretty long, so here's the easy way to do it. Just do a search on "prehistoric insects," then type "ask a biologist" with it. We'll be a number one hit.

The Ask a Biologist podcast is produced on the campus of Arizona State University, and is recorded in the Grass Roots Studio, housed in the School of Life Science, which is an academic unit of the College of Liberal Arts and Sciences.

Remember, even though our program is not broadcast live, you could still send us your questions about biology using our companion website. The address is, or you can just google the words "Ask a Biologist." I'm Dr. Biology.

Transcription by CastingWords

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Time Traveling Paleoentomologist

Audio editor: CJ Kazilek

Inner Space the Final Frontier

You hear that space is the final frontier, but could we have another frontier right here on Earth? The microscopic world offers a limitless opportunity to explore amazing places and life forms. You just need the right tool for the trip – a microscope. Guests Angela Goodacre and Doug Chandler have a conversation with Dr. Biology about the instruments that let us journey into inner space.

Angela Goodacre in front of a microscopy inspired painting by Doug Chandler

Content Info | Transcript

MP3 download | 16MB

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Topic Time
Introduction 00:00
How long have microscopes been used? 02:36
Who are the two people who first documented using a microscope? 03:10
What do you need to make a microscope? 03:33
Robert Hooke's first book about microscopic world and interesting pieces of history. 05:00
Antonie van Leeuwenhoek - his microscope and his animalcules. 04:46
Some of the scientific breakthroughs that happened because we had microscopes. 05:47
Microscopes used to detect cancer. 07:49
What are some of the many types and shapes of microscopes? 09:12
How does a microscope compare to a camera? 10:03
Sites to explore amazing images made with microscopes. 12:04
Molecular Expressions - all about microscopes - Ask A Biologist Image Gallery 13.41
Go out and buy your own microscope to explore the microscopic world. 15:06
The different types of microscopes. 15:50
Labeling different parts of cells with colors. [mitochondria] 17:58
Advantage of using colors that are invisible to the human eye. [color spectrum chart] 19:09
Summary of light and florescent colors. 20:12
Electron microscopes. [photons and electrons] 20:29
Basics of light and electron microscopes. [photon and electron wavelengths] 21:21
What is resolution? 22:41
When and why do we use a light or an electron microscope? 23:56
Three questions. 26:06
When did you know you wanted to be a biologist? 26:15
What would you do if you could not be a biologist or microscopist? 27:53
What advice do you have for someone who wants to become a biologist? 29:16
Sign-off. 30:59

Transcript - (PDF)

[beeps – electronic lock and vault door opening]

Dr. Biology:  This episode of Ask A Biologist is being pulled from our special collections that have been stored in our secret vault. This is Ask A Biologist, a program about the living world and I'm Dr. Biology. Allow me to start the show off with the opening lines from one of my favorite television shows. I've actually always wanted to do this, so, here's my chance.

[reverb effect voice]

Dr. Biology:  Space ‑‑ the final frontier. These are the voyages of the starship Enterprise. Its continuing mission, to explore strange new worlds, to seek out new life and new civilizations, to boldly go where no one has gone before.

[end of reverb effect voice]

Dr. Biology:  I'm sure many people know that these lines come from the show, which is the original Star Trek, or the more recent one. They've either seen the show, or there are a lot of movies out now. While the characters of Star Trek were exploring strange new worlds in outer space, there are also as many, if not more, strange new worlds right here on planet Earth.

To find them, you need only to look at the very small, or inner space, instead of outer space. In today's show we'll be talking about inner space, microscopes and microscopists, or, as I like to say, micronauts, because they get to explore some of the most amazing worlds you can imagine.

With me are two micronauts. Doug Chandler, a professor in the ASU School of Life Sciences. Dr. Chandler is also the co‑director of the School of Life Sciences Bioimaging facility. You could think of it as the NASA for the School of Life Sciences. This is where the biologists at Arizona State University come to do their own exploring, finding their new life forms in worlds that are just unbelievable sometimes.

We also have a visiting scientist at ASU, Dr. Angela Goodacre, from Olympus. In case you didn't know it, Olympus makes more than cameras. They also build some amazing microscopes that are used by scientists around the world.

If you give us a moment, we'll also give you some great websites that you can visit and explore. Even if you don't have your own microscope, you'll be able to go and look at some of these worlds that biologists and scientists around the world are finding and posting up on the website.

Welcome to the show, Dr. Chandler.

Dr. Doug Chandler:  Thank you, Dr. Biology.

Dr. Biology:  And welcome, Dr. Goodacre.

Dr. Angela Goodacre:  Thank you, Dr. Biology. I'm happy to be here.

Dr. Biology:  Before we journey to the strange new world of inner space, let's talk just a bit about the microscope. How long have microscopes been in use?

Doug:  Quite a long time. Originally, people didn't even have glasses or spectacles. An Italian invented the spectacle. Soon after, we all know about Galileo and his telescope. Although, there's actually another guy involved there that's not well known. Within a year later, in the 1600's, came a microscope. It wasn't until a hundred years after that, that van Leeuwenhoek got going in the Netherlands.

Dr. Biology:  The microscope's been around for about 300 years. We know actually two characters in history that are really well known for the microscope. One is Robert Hooke, and the other one is Antonie van Leeuwenhoek. One was Dutch. Is that right, Doug?

Doug:  Yes.

Dr. Biology:  The other one was...

Angela:  British.

Dr. Biology:  Well, when we start with a microscope, Angela, what do we have to have to be a microscope?

Angela:  Well, you need glass lenses that will allow you to blow up the image that you're looking at, so that you can see the fine detail. A long time ago, you had to be able to draw what you saw through this glass. Nowadays, of course, we use cameras. It's made life a lot easier for those of us who are artistically challenged.

Dr. Biology:  That's a really good point. There weren't any cameras when they started. The first book that Robert Hooke produced was a wonderful series of illustrations based on what he saw through the microscope. One of them is from cork. I love the neat thing about this, because he could look at the little, what he called cells, in the cork, which actually became the name that we use today to talk about cells, the smallest unit of life.

The other really curious thing that I found, when I was looking up Robert Hooke, is he illustrated a really exquisite flea. Turns out, that flea was the one that was going through Europe at the time, and was responsible for the bubonic plague. In a way, it's good that he survived, considering he was actually illustrating fleas that could have been carrying the bubonic plague.

Let's talk at a little bit this other character, Antonie van Leeuwenhoek, the Dutchman. His microscope is a little bit different, though, than the compound microscope that we might have been talking about with Angela here.

Doug:  Well, yes. He used a single lens which is almost like a drop of glass. He was a perfect craftsman in making these. In fact, he considered it a trade secret because he knew that he made the best glass lenses around at that time. No one else could equal seeing what he saw because of his lenses. He kept it a secret to himself. Because he made such good lenses, he saw all kinds of little animal life, animalcules as he called them. He loved the ones that moved.

Dr. Biology:  Alright. What are some of the scientific breakthroughs that have happened because of the microscope? I mean we're talking 300 years. There have to be things that without the microscope, we would have been stuck.

Doug:  Well, one of the biggest things is the organelles within the cell. Hooke may have been describing whole little animals, and van Leeuwenhoek little single cells. Soon the lenses became even better than van Leeuwenhoek's. Although it took another hundred fifty years that people were seeing things within cells, like the nucleophile chromosomes, mitochondria, and other such so‑called subcellular organelles.

Dr. Biology:  Right. Organelles, meaning literally tiny organs. I think it's great, but I know there's some more out there. Angela?

Angela:  Without the microscope, in vitro fertilization would not have been possible. Parents who couldn't have a baby by normal means, were able to have a baby conceived in a test tube, and then grow up in the mom.

Dr. Biology:  We just recently had a big push on standing up against cancer, a really big telethon. It's something that we've been battling globally. The microscope has a really important role with the study and the possible cure, and/or treatment for cancer.

Angela:  Yes it does. You can take cancer cells, and try out new forms of chemotherapy. This is chemicals that will selectively kill cancer cells, and leave normal cells unharmed. When doctors are trying to develop new therapies for cancer, sometimes they will do this with cells that are grown in a dish. Then, they will observe them in a microscope, and treat those cells with these chemicals, to see if these represent an effective cure for cancer.

Dr. Biology:  Not only are there drugs that are being able to be designed to treat cancer, another problem with cancer, from what I understand, is finding out when someone has it. Not only finding out when someone has it, but finding out early on. I believe you actually were talking about some really interesting possibilities using a microscope.

Angela:  Yes. There are ways to look inside the human body using modified microscopes. Probably some of your listeners will have parents or grandparents who go and get a colonoscopy. That can show very early signs of cancer at a time when it's early enough to treat that, so that your parent or grandparent will be cured.

That's a different type of microscope. It's used in the human body. The other thing that microscopes can be used for is to look at cells that are taken from somebody who has a cancer. The doctors can look at those cells in detail, discover what kind of cancer it is, and what's the best treatment for that cancer.

Dr. Biology:  Right. When you mentioned about the microscopes inside the body it brought to mind the fact that a lot of us think about the microscopes we see in either high school when we're growing up or maybe when we went to college. They have a certain picture in their mind. These microscopes today have all sort of shapes. Obviously, if you're going to go inside the human body, they've got to be really small, and they have to be very flexible. That's pretty cool stuff.

Doug, you actually do quite a bit of research with cells yourself. You're a cellular biologist.

Doug:  Yes. Even moving cells, like van Leeuwenhoek.

Dr. Biology:  Can you talk just a little bit about what you've been doing in the lab?

Doug:  We have some of the same interests as van Leeuwenhoek. That is, looking at how cells move.

Dr. Biology:  So now are you taking a microscope, and maybe connecting a video camera?

Doug:  Definitely.

Dr. Biology:  As someone who came from the art background, it was curious to me as I was a photographer ‑‑ I am a photographer ‑‑what happened was, for me getting into microscopy was very easy because all I was doing is sticking another part of an instrument onto, basically, a camera.

Angela:  A microscope is pretty much like one of those zoom lenses on your camera. You press a button, and you zoom in, and you can see things that are far away. With the microscope, we're not so much looking at things that are far away, but we use that zooming in capacity to make the image larger, so that we can see more detail in the image.

Dr. Biology:  Right. Where we first see just the surface of skin, we zoom in a little bit further and we see the cells making up the skin. We zoom in a little bit further and we look inside the cells and we see the organelles that are inside there. We can go into one of the organelles.

For example, we can go into the nucleus and we can see the DNA that's inside there. As we go further and further in, we get more details.

Doug:  That's an excellent analogy. The components of a camera work very similar to those of a microscope.

You have glass lenses that magnify things and focus things. You have light gathering capabilities. You're trying to gather the light from a landscape and focus it onto film. That's going to be your image that's recorded on film or on your digital chip in your camera.

Then you have a permanent image that's a representation of what you or the camera saw. The same thing happens in a microscope. You attach the camera to the microscope. You just have an additional set of lenses to make things look bigger. You focus them on the solid state chip or film and you've got an image that's preserved.

Dr. Biology:  I see these wonderful images and I said we'd talk about some websites out there that people can go to and explore. One of them, Angela, is the company you work for. It's called Olympus Bioscapes.

I don't want people to miss the address. Don't worry about the "http" stuff. It's just There are some amazing pictures up there. Now you said there are videos, too?

Angela:  Yes. The Bioscapes Competition is organized by Olympus. Other microscope companies, like Nikon, also have competitions.

The one that is organized by Olympus, called Bioscapes, is looking for images that are taken using light microscopes. They are looking for scientific interest, but also the artistry behind it, whether it is an interesting composition.

This is open to all kinds of scientists throughout the world. You can submit either still images or you can submit movies.

Nowadays, with light microscopy, we like to be able to take pictures of living cells and even moving animals. Little animals and even big animals, anything that you take with a microscope you can submit for this competition.

Dr. Biology:  All right. You mentioned Nikon. Nikon has what's called "The Small World" and that's If you want to learn more about microscopes themselves, you want to go to a site called Molecular Expressions.

The best way to find that is type those two words in Google and you'll find the site. They have tutorials and they have movies and they have pictures and they have ways to use microscopes. It's a great place to go.

Also, Ask A Biologist has always had a gallery. We have a mystery image gallery. You can go in there and there are some really spectacular images. One of them, Doug, is work from your sea urchins. It's the one, it looks very out‑of‑this‑world. It looks like a bunch of planets.

Another one is ‑‑ well, I like to say that science is literally at our fingertips. This one is sweat on a fingertip. It's a scanning electron microscope picture of sweat on a fingertip. You've got to go see it.

Finally, we've added some really great galleries that allow you to now zoom in and zoom out as if you had your own private microscope. Even if you don't have one in school or if you don't have one at home, stop in to Ask A Biologist. You can start first with bird feathers and we're going to have one up on pollen grains. Go there and I know we're going to have a lot more in the future.

Doug:  I'd also like to encourage you, if you find Ask a Biologist interesting and some of those pictures fascinating, you, too, can have your own microscope at home. There are microscopes available at virtually every store that caters to "playing with science".

I remember as a little kid I got one of these microscopes, probably from Sears or something like that. I was daring enough to prick my finger and look at my own blood underneath it.

Dr. Biology:  Oh, really?

Doug:  Yeah. All these cells were moving around. It was really cool. I could relate to van Leeuwenhoek.

Dr. Biology:  If you don't want to prick your finger, you can go out there and get some really scummy pond water. That's another wonderful thing to look at because you can find some things in a drop of water that you couldn't believe.

Now, let's go a little bit further here with the world of microscopy. We began to talk about, they don't all look the same. A microscope is not just like every other microscope.

If you imagine walking into a hardware store and you look in the tool aisle, you might see a dozen different kinds of hammers and you might see at least that many kinds of saws. Even though they are all called hammers and they are all called saws, they each have different purposes. They work better for some situations than others. Let's talk about the different types of microscopes.

Angela, could you talk about the different basic ones that we have?

Angela:  Many microscopes use light. There's light that is just white light and then you look at a pink or purplish colored dye on a piece of tissue. Then there are other microscopes that use a different kind of light. This is called fluorescence, just like fluorescent lights that you might have in your home.

But fluorescence can be made in many different colors. You can put chemicals into a cell, which will attach themselves to very specific things within the cell.

Dr. Biology:  These are the little organelles.

Angela:  These are the organelles or even specific molecules. You can tag these molecules or organelles with a color that represents that molecule or that organelle.

Then you can look using fluorescence microscopy and you can watch individual organelles move around the cell. You can see other cells interact with the cell that you're looking at. You can see cells in the bloodstream. You can see molecules moving between cells.

You know what you're looking at because every molecule of a certain type is going to be labeled or tagged with a specific color.

Dr. Biology:  Oh, yes. It's kind of like if you got to look into the cells and you get to see a bunch of things [audio breakup] have red, some of them might be green, some are blue. If we're going to talk about an organelle, let's pick one.

For example, Doug, you work with sperm. Sperm have to do a lot of swimming, which means it takes a lot of energy. They have to have a lot of mitochondria.

We might have a particular kind of label, these kinds of chemicals that attach themselves to the mitochondria, so we can see how much mitochondria is in that particular sperm cell, right?

Doug:  That's right. Sperm cells have a whole group of mitochondria just below what is called a flagellum. That's really just the tail that whips back and forth and makes the sperm swim. We could use a colored dye that's fluorescent and that's specifically designed to be taken up by mitochondria and color them red.

Angela:  Then you can color the nucleus blue and you could color other parts of the cell yellow and green and you can look at the way how all these organelles interact with each other. One of the cool things about using cameras on a microscope now is that we can use colors that are invisible to the eye.

Just like insects can see into the ultraviolet range, this is colors that are invisible to us but they are perfectly visible to a bumble bee looking for a flower to pollinate.

We can extend our range of colors, our palette of colors, if you think like an artist palette, not only for the colors of the rainbow from red to violet, but we can go infrared and we can go ultraviolet. Some of our cameras can record these colors for us.

Dr. Biology:  We have a color spectrum on the Ask A Biologist website. If anybody wants to see that spectrum including the ultraviolet and the infrared, they can do that. I recommend it because it gives you an idea of how much we would be missing if we couldn't do that.

We have light microscopes that can see the visible light that's visible to humans and we also have the microscopes that work with fluorescent colors. Those could be colors that we do see, and some of them we can't see but the cameras are able to see. What other kinds of microscopes do we have, Angela?

Angela:  We have electron microscopes.

Dr. Biology:  Electron microscopes?

Angela:  Yeah. Instead of using light, which is made up of photons, the electron microscope looks at electrons.

Dr. Biology:  OK. Doug, you're actually, if I'm not mistaking, one of the big areas you spend a lot of time in is electron microscopy. I think you've written a book on this, haven't you?

Doug:  Yes. Both light and electron microscopy.

Dr. Biology:  What's the title of it?

Doug:  It's called "Bio‑imaging and Current Concepts in Light and Electron Microscopy".

Dr. Biology:  Not everybody is going to go pick that up, but I'll tell you, it's got a lot of really cool pictures in it. Let's talk a little about light and electron microscopes. Why are we using electrons instead of these photons that come from the Sun?

Doug:  It seems surprising because you can't even see electrons. The only way you can detect them is by film, you'd take a picture of electrons, or by a phosphorescent plate that will change electrons in the light.

Dr. Biology:  Why electrons instead of photons? I can go get a light bulb and do that very easily. I'm assuming it's not as easy to make a microscope that uses electrons. Why would I want to use those?

Doug:  Electrons seem like a particle to some scientists but they seem like waves to others. In the microscope we're always using waves. The electron, it turns out, the way it goes through our specimens and interacts to form an image of the specimen is acting in a sense similar to a photon.

There's one big, big difference, though. The wavelength of the electron is much smaller than that of the photon. That means it can see little details of the specimen that a photon could never see.

Dr. Biology:  Right. Let me get this straight. You have photons that have these big waves and you have electrons that form these really tight waves and because of the wavelength they're able to see much more detail in really, really small things.

I bet someone's going to start mentioning a word that we use a lot but not necessarily the way we want to use it in the show, and that's resolution. What, on Earth, is resolution? This is what we're going to get to when we talk about the difference between looking at a light microscope and looking at an electron microscope.

Angela:  Resolution is how close together two points can be, and yet you can still tell that they're two separate points. Higher resolution means a smaller distance between those two points.

Dr. Biology:  If we're able to see something like two atoms as two separate atoms, that would be really good resolution.

Angela:  It would be really good, and you wouldn't be able to do it with a light microscope.

Dr. Biology:  What we typically look at with microscopes in school or anywhere else, what would be the best resolution we can possibly get just with a white light?

Doug:  It would be a fraction of a micron, which seems small but you would have to put billions of atoms together to make that distance. Instead, we're looking at bigger things like subcellular organelles.

Dr. Biology:  If electron microscopes are able to see much smaller detail than the light microscopes, why don't we just use electron microscopes? Why isn't that the only microscope we use?

Doug:  It's hard to look at a live cell inside with the electron microscope because electrons only work in a vacuum.

Dr. Biology:  Like out in space?

Doug:  Yeah. Out in space.

Dr. Biology:  What is it that we can see with an electron microscope that we can't see with a light microscope? Do you have some examples for me?

Angela:  In the light microscope we can see an individual cell, we can see the nucleus, we can see the mitochondria. But in order to see the cell membrane itself we'd have to turn to electron microscopy. Another example would be, we can see bacteria in the light microscope but we can't see viruses. That's why we have to go to electron microscopy.

Doug:  Microscopy, especially electron microscopy, is important to the medical sciences. At the light level you look at the tissue that might have a pathology, maybe cancer. You recognize that. Then you go to the electron microscopy level and find out what parts of the cell are unusual.

For example, there are whole new sets of cellular structures that have been seen only with the electron microscope. The cell membrane, that covering that surrounds the cell that's so important in the cell not only interacting with its neighbors but it's the part of the cell that is attacked by viruses and bacteria, it wasn't even seen until electron microscopy was invented.

It would be like, we know what your house looks like and we know it has a kitchen and a dining room and a living room, and we know there's a really gigantic big screen TV in the living room but we don't even know what kind of walls make up your house. We couldn't see them. They're so thin that our microscope can't see them. With the electron microscope we can tell that you must live in a brick house.

Dr. Biology:  OK, you two micronauts, before we get out of here, I always ask three questions. I'll start with Angela. The first one is, when did you first know you wanted to be a biologist or a scientist? Was there a particular spark in your life that you can remember?

Angela:  I think that I became a scientist because I always liked math.

Dr. Biology:  Really?

Angela:  Maybe, I was being a little bit lazy. I could sit down and take a math exam without having done any studying, whereas for history I had to hit the books and really study hard.

Dr. Biology:  So your introduction into science was through mathematics?

Angela:  It was, yes. That started just by adding up numbers. I have always been fascinated by numbers. Then, when I started looking through the microscope, it just seemed to make sense. It's the sense of discovery.

Dr. Biology:  How about you Doug? What was the spark for you?

Doug:  It just shows that people who end up in science can get there by many routes. I had two favorite hobbies since I was in high school. One, I really liked art, and I still do some painting and things like that.

Two, I really like biology and I was influenced so favorably by one of my favorite high school teachers who taught Advanced Biology. Probably all of you know, you have a few favorite teachers yourself, and you know how much they impart to you in excitement.

That's the kind of excitement I had when I met my high school biology teacher. It seemed inevitable that somewhere in the distant future that I would bring art and biology together and become a microscopist.

Dr. Biology:  I can see you are both hooked on this, and you're passionate about it. My next question is what are you going to do when I take it all away from you? You can't be a biologist or a scientist. Certainly, you can't use a microscope. What are you going to do, what are you going to be, Angela?

Angela:  I'm going to be an explorer.

Dr. Biology:  An explorer?

Angela:  Yeah, go all over the world looking for wild life, plants, animals.

Dr. Biology:  OK. I'm going to let you go away with that because I think there are some biologists that get to do that, too. I think you brought up a really good point. A lot of people if they want to do some exploring, they want to travel, biology is a great way to do it.

All right, Doug. I might know the answer to this but I'm going to take it all away, no science, no biology, none of those things. What are you going to be?

Doug:  I only get one choice?

Dr. Biology:  You only get one choice.

Doug:  Oh man, that's tough. Mine is very ordinary. It used to be that every kid wanted to be a policeman. I think most kids these days want to be a rock star and that's what I want to be.

Dr. Biology:  You want to be a rock star? I thought you were going to say you wanted to be an artist. I forgot to mention, Doug also has the cover of one of the Sols magazines. It's one of his paintings. It's a fabulous painting. You go into the Sols website,, and you can see some of these really cool images.

All right. One more question for the two of you. What advice would you have for someone who wants to become a biologist or just a scientist in general? Angela, even a mathematician?

Angela:  To get very familiar with computers because every time we take an image through the microscope these days, it's going to be stored on a computer. You really need to have a good understanding of where your images are stored on a computer, how to get them, how to label them so you know exactly what you did to get that particular image. I think these are important things in preparing to be a scientist, particularly if you want to be a microscopist.

Dr. Biology:  OK, and Doug?

Doug:  My advice is more general. I think anything that you really want to do, you want to do because of motivation. Where do you get that motivation? I think you look to other people that are doing the things that you find interesting and that you would like to do.

If you think science is kind of neat, look around the web, then go to that science teacher that you think is maybe doing some really weird stuff or cool stuff, as the case may be. If you like art, find somebody who can tutor you in art, who really loves art. Whatever you like to do, go to a person that can make it exciting for you, who can give you the motivation to really work on it.

Dr. Biology:  Professor Chandler, thank you visiting with us.

Doug:  Thank you.

Dr. Biology:  Dr. Goodacre, thank you for joining us on Ask a Biologist.

Angela:  Thank you.

Dr. Biology:  You have been listening to Ask a Biologist, and my guests have been Professor Doug Chandler from the ASU School of Life Sciences, and our special guest Dr. Angela Goodacre from Olympus.

The "Ask A Biologist" podcast is produced on the campus of Arizona State University and is recorded in the Grassroots Studio housed in the School of Life Sciences, which is an academic unit of the College of Liberal Arts and Sciences.

And remember, even though our program is not broadcast live, you can send us your questions about biology using our companion website. The address is or you can just Google the words "Ask A Biologist". I'm Dr. Biology.

Transcription by CastingWords

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Inner Space the Final Frontier

Audio editor: Eric Moody

Hi, Andi.

What a great question! You may have heard that the oldest human lived to be 122 years old. But that amount of time only makes a small fraction of the lifespan of some other living things. Identifying the oldest organism gets a bit complicated when we start to think about what we consider an individual organism.

Question From: Andi
Grade Level: 8

Answered By: Karla Moeller

Have a different answer or more to add to this one? Send it to us.

Rebooting the Immune System

Remember your last paper cut, or the bad cold that had you coughing and blowing your nose? It was your immune system that was busy trying to make you better by battling the bacteria or virus that was attacking your body. How your immune system works is the discussion Dr. Biology has with pediatrician Paul Turke. They also talk about how our immune systems have to reboot to keep up with evolving bacteria and viruses.

Background T-cell image from NIAD/NIH

Content Info | Transcript

MP3 download | 15MB

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Topic Time
Introduction - with basics of the immune system. 00:00
What is the immune system? 01:44
Cast of characters - the cells of the immune system 02:20
Why the immune system needs to reboot. 02:36
Nature versus Nurture and how it relates to allergies 04:46
T-cell education 09:18
You are called a Darwinian Pediatrician - what is that? 12:42
How did your journey in science lead you to become a doctor? 15:21
How does anthropology fit into the practice of medicine? 18:48
Are there misconceptions between an evolutionary pediatrician and a traditional pediatrician? 19:41
Sports and steroids 22:34
Three Questions 24.16
When did you know you wanted to be a scientist - physician? 24:26
What would you do if you could not be a biologist or physician? 25:33
What advice do you have for someone wanting to be a biologist? 26:16
Intro to the book 27:04
Reading from chapter one of Bringing Up Baby by Paul Turke. 27:35
Sign-off. 30:27

Transcript - (PDF)

Dr. Biology:  This is "Ask A Biologist," a program about the living world, and I'm Dr. Biology. Let's talk a bit about something very important to all of us, "Our immune system."

Now in case you missed it in class, our immune system is our defense against attacks from things like bad bacteria and viruses. It helps us keep from getting infections when we get a cut. It also helps us battle things like the common cold, and it defends our body from much nastier diseases.

In Ask a Biologist, we even think the immune system is so important that we created a comic book on the subject. It's become a favorite of kids of all ages. It's called "Viral Attack," and it tells the story of how a collection of special cells protects you.

It includes, among others, the macrophage. Macrophage, it's kind of a fun name. It means big eaters because they eat the bad bacteria.

There are also other cells, B cells, and the T cells. The T cells have this really powerful cytotoxin that they use to destroy bad cells, or cells that are infected.

Our guest today also thinks the immune system is one of the most important systems in the body. Dr. Paul Turke is a pediatrician and adjunct clinical faculty member of the Department of Pediatrics and Infectious Diseases at the University of Michigan.

He's at ASU giving a talk at the Center for Evolution and Medicine about the human immune system and how, when and why it needs to reboot. Let me give you a hint, it's not like rebooting your home computer or smartphone.

Welcome to the show, Dr. Paul Turke, and thank you for visiting with me today.

Dr. Paul Turke:  Well, you're welcome. I'm happy to be here. Thanks for inviting me.

Dr. Biology:  Before we jump into rebooting our immune system, can we first talk a bit about how it works?

Dr. Paul:  Sure. The immune system is a very complex part of our bodies, probably second most complex to the brain. It is that way because it has to figure out what is the body, that doesn't need to be attacked, and what is foreign, like a virus or a bacterium, that could do us harm and it does need to be attacked. That's a difficult thing to do, and so the immune system has to be pretty complicated in its structure in order to do that.

Dr. Biology:  As we talked about at the beginning, there are a cast of characters, as I would call them, and these are the different cells that are part of the immune system. I talk about the macrophage and the B cells and the T cells. All of these have a very particular role.

Dr. Paul:  Exactly. They do.

Dr. Biology:  It sounds like a system that is pretty much perfectly worked out, so why does it need to reboot?

Dr. Paul:  It is pretty much perfectly worked out, but it's not perfectly worked out. There are two general answers to that question. They're both, I think, equally important.

One is that the immune system gets old. The word for that is senescence. You have to at some point, for everything, start over. That starting over is rebooting.

But there's another angle for the immune system that you have to take into account in. That is the germs, the things that infect us, they change quickly. They evolve very quickly. You can build this great immune system that has a great memory for fighting all the usual suspects. Then time passes and the usual suspects have changed, so you have to reboot and start over.

In humans, we recombine our genes with another person. That allows us to create a huge variety of cell types to fight all these changing germs. We have to do that periodically, and we do that by making children. That's the time when the immune system basically reboots. It's when we start over again with reproduction.

Dr. Biology:  The rebooting happens at birth?

Dr. Paul:  Yes.

Dr. Biology:  It's not something that you and I do periodically as...

Dr. Paul:  Yeah. We do sort of miniature, minor rebooting in our lifetime. The immune system cells have this gene change mechanism built in. It allows them to mix things up and it gives us a good way, but a relatively limited way to produce variety to deal with the new variety that germs are always posing for us.

To really do it well, you get to a point where you have to start over. It's like you can fix your house up and add this and add that and make it better for what you need right now. But it ultimately, at some point, you got to tear down the old house and you got to build a new one. That's what we do with the immune system, and that's the most fundamental way of rebooting.

Dr. Biology:  Is there an important role to the environment? For example, a lot of people hear "Nature versus nurture." In other words, you talked about the genetics, when we make babies. We're actually going to get into the genetics of rebooting your immune system.

There's another role, it seems like that once the baby's born, there is an environment they come into. The reason I'm asking this is there's a lot of discussions about allergies, in particular. A lot of babies are...Young children appear to be having more allergies. Where are we on this?

Dr. Paul:  That's a great question. I'm actually going to talk a little bit about that today in another talk I'm giving. Yeah, I think that we get exposed to allergens in new and different ways than we used to in the past.

That confuses the immune system at times. It messes with what I talked about earlier, the most important thing the immune system has to do or the most fundamental thing is it has to distinguish between self and non‑self.

When it comes to things like, let's say peanut allergies, a lot of children are allergic to peanuts, and they are severe allergies. You have to figure out, or the immune system needs to figure out or should figure out that peanut antigen, the proteins in peanuts, are not the enemy.

It's a process of learning tolerance. It turns out it has a lot to do with when you were developing an immune system is first exposed to peanut protein. Allergists, because it's been such a dangerous allergic reaction, they went to recommending for years now that moms who are pregnant avoid peanuts altogether.

We were told from allergists not to pick on allergies, but we were told, "Don't let kids have peanuts until they get older. Until they're two or three years old."

If you think in the broader context of the immune system, being part of an arm's raise between germs and ourselves and having to distinguish between self and non‑self, there's a critical period for learning about tolerance. That critical period turns out to be when we're very young, largely when we're still a fetus inside the uterus.

When we're still a fetus, there's some special things that go on. We're protected, more or less, from outside threats. The things the immune system encounters while we're a fetus tend to be things that the immune system can count on being self. That's when the immune system learns tolerance. It learns to ignore certain things.

It's probably the exact wrong thing to do is to not give pregnant moms peanuts because when you don't do that, then the fetus doesn't get exposed to peanut antigen. Six years later, when the child gets exposed to the peanut butter or something, it recognizes as a potential foreign substance that needs to be attacked.

That's the problem. All of these can be deduced on theoretical grounds and in fact, I've been telling my patients for years, "I think it's probably safe to eat peanuts while you're pregnant."

But in 2014, at the end of the year, I think in one of the biggest and best medical journals out there, there were a couple articles published showing, in fact, that if moms ingest peanuts and peanut butter while they're pregnant, the baby that is born has a much, much, reduced chance of developing peanut allergy.

Dr. Biology:  Of course this is when we're talking about the mom that does not have a peanut allergy...

Dr. Paul:  That's a really astute point. In fact I have a patient who is very allergic to peanuts. His mom is very allergic to peanuts, but I didn't know that. When she's told me she was pregnant with a new baby, I said, "Oh well, you have to eat some peanut butter so that that new baby doesn't have a problem." She says, "Well, except for the fact that that would likely kill me because I have a severe peanut allergy, so that's the problem."

It's not totally a dead end there because there could be ways, in theory, of introducing peanut antigen to the fetus or the young child and avoiding exposure to mom. It'd be more difficult than simply having mom, who's pregnant to eat a peanut butter sandwich, but there's still potential ways of doing that.

Dr. Biology:  If we get back to our rebooting of the immune system, there's a topic that you're going to be talking about this afternoon. I'm going to be very interested in learning more about, but if you can talk a little bit about now. It's what you call "T Cell Education."

Dr. Paul:  Yeah. What happens is all your blood cells, including all your white blood cells which comprise the immune system, they get made in the bone marrow. They migrate from the bone marrow. The ones that are destined to be T cells move into the thymus. They move into there. In fact that's where they get their name – thymus begins with T, T cells.

What happens there, this is a bit of a simplification. A lot of things happen there, but sort of the main thing that happens is every young T cell has a receptor, and when it's in the thymus, it's presented with antigen. Those are proteins with shapes. If that antigen fits tightly in that T cell receptor, then the T cell in question sent signals that make it commit suicide, or apoptosis is the word.

The reason for that is the antigen you're being presented in the thymus is supposed to be self‑antigen. You want to get rid of those T cells that will react to self before they get out into the periphery and can do things like attack your liver or your pancreas.

They undergo apoptosis if they bind tightly with antigens when they're presented with it in the thymus. All of that, as you probably figured out by now, depends on the thymus truly being a privileged place where only self‑antigen is presented.

But remember we talked earlier about an arm's raise about germs being devious little things. If you're a germ and you want to gain free rein, you want to hide from the immune system, get yourself presented in the thymus.

What will happen then is T cells that would react to you and orchestrate an army of other cells to fight you will get deleted before they can do that. Germs have had a strong evolutionary incentive to get their antigen presented in the thymus.

Again, we go back to the best time to be assured that the antigen being presented in the thymus is truly self‑antigen is, while you're a fetus, because you mom's immune system's protecting you. Along with all kinds of other things, like you're wrapped in membranes, you're inside a uterus, you're not exposed much to the outside world.

That's the time when you want to start over. You want to reboot. You want to rebuild this huge new T cell repertoire to fight things. It's the time when it's most reliably true that you're only letting T cells out that will react to foreign things, not self‑things.

Dr. Biology:  So there's a T cell library in there.

Dr. Paul:  That's right.

Dr. Biology:  All those are the good books, the good library of cells, and those are the ones that can be trusted?

Dr. Paul:  The good books are the ones that don't react to self. The ones that are made to commit suicide are the ones that do react inside the thymus, and they react too strongly to self, and so they get deleted.

It's an education process is how immunologists sometimes refer to it. You go to school in the thymus as a young T cell, and you only get to graduate if you don't react to self.

Dr. Biology:  Very good. Now, you're called a Darwinian pediatrician. Can you talk a bit about what that means?

Dr. Paul:  Yeah. Back when what's now usually called evolutionary medicine was getting its start, one of the key papers published that is noted as the starting is one called "The Dawn of Darwinian Medicine." It was published by Randy Nesse and George Williams.

The Darwinian term got replaced with, evolutionary for a number of reasons. One is that, in some people's minds, Darwinism evokes this survival of the fittest idea, It can lead to the notion, especially when you're a pediatrician, that we're only going to take good care of the fittest children, or something like that.

Of course, it doesn't mean that at all. It means that we're using Darwinian or evolutionary principles to figure out new and better ways to take care of all children. We're not making any judgments about which ones are good, or which one should be privileged or not. We love all children, Darwinian pediatricians do, or evolutionary pediatricians do. All we're trying to do is figure out ways to better care for all of them.

Dr. Biology:  Are there other doctors that call themselves Darwinian physicians? Or evolutionary physicians?

Dr. Paul:  Yeah, there's a small number, but a growing number, that refer to themselves as evolution‑minded or evolutionary internists, or whatever it may be. It's something that we talk about more in academic circles than we do in the clinic.

Even people that don't think evolution is a fact can benefit from, evolutionary medicine. We might think in evolutionary terms when we're trying to advise them to treat a fever, which is part of the immune system's response to help fight germs.

I don't think anybody puts a sign out on their door saying Darwinian or Evolutionary Physician because, unfortunately, half the US population would probably be turned off by that. We do proudly call ourselves Darwinian‑minded, very many of us do. There's this growing, growing movement.

Randy Nesse here, at ASU, is one of the leaders of it, and has been promoting it for years and years and was one of the founders of it. I was there in the early days, too. Five or six of us used to meet once a month at the University of Michigan in the hospital and talk about this new thing and new ways we could use evolution to further medicine in general.

This was long before I was a physician, by the way. It's one of the things that led me, at the age of 39, to go to medical school. I was very much stimulated by those ideas, and it pushed me down that path.

Dr. Biology:  Actually, this is very timely for you to mention that. I noted that your path of becoming a physician was a bit different than most doctors.

How did your journey in science bring you to the realization you wanted to be a doctor?

Dr. Paul:  I always loved children, and I was always interested in health‑related issues, but I never really wanted to be a doctor until I was doing field work in Micronesia and I met two doctors who happened to be there.

They were doing service in an underserved area in order to pay back their medical school loans. We became pretty good friends. One was from Yale, and the other one was from Penn.

I had a young daughter with us at the time. She would pick up things. I was filled with admiration because I, as an anthropologist, couldn't do all that much to help her, but they, as physicians, really could. I thought, "Wow. This is really interesting stuff."

When I got back to the University of Michigan and this evolution of medicine thing was being started up, that just furthered my interest. I eventually got to know a really smart guy named Richard Miller who was an immunologist at the University of Michigan.

He was one of the few people at the time who had an MD and was doing great work and was well‑received in the field who was thinking evolutionarily. By luck, I joined with him and some of his postdocs who were also doing this. Kevin Flurkey was one that was very influential to me.

I started to get interested in the evolution of the immune system. T cells were his focus. Kevin and I, we were very interested in why the thymus is so vigorous and works so well in utero, and then starts to fade away once we're born.

By the time we're adults, there's not much left of it. From what we talked about earlier, I kind of gave that answer. The time for the thymus, when it can best do its job, is while it is at the fetal stage.

I decided at that point, from working in Rich's lab, after learning some immunology, that I really liked this stuff. I decided I was going to go to medical school, but not to be a practicing physician, but just to get the MD so that I would have some chance of being hired in a microbiology or pathology department of some university.

When I got there, you do a lot of patient stuff in medical school, and I found out that I really liked treating and interacting with the kids.

In the end, I ended up pretty much as far away from joining an immunology lab somewhere and not seeing patients and just being in academia. I ended up opening a private clinic where I could work with kids and try to use my evolutionary and anthropological background to help everyday kids coming in with their moms and dads.

Who have their runny noses and their fevers and their ear infections, and so on, and to use evolutionary principles to figure out new and better ways to treat them, to tweak things, really.

I don't want to make it sound like it's revolutionary if you understand evolution, oh you can fix everything. It's not that, but there are little things, subtle things, and some not so subtle things that you can do if you have evolution in mind when you're running a community pediatric practice.

Dr. Biology:  How does anthropology fit into the practice of medicine.

Dr. Paul:  Well, in pediatrics, it teaches that there are lots of ways to raise healthy happy children, and so it allows me, as a pediatrician, to be more flexible than some of the old‑fashioned pediatricians who used to say, "No, you have to do it this way. You have to throw away the bottles when they're 12 months old. You have to have them sleep in this condition or this environment, and not that condition."

Once you're an anthropologist, you know there's lots of ways of doing things. There's lots of good ways of doing things, and you can be more flexible. I think that is something that parents like, especially in this day and age where we've got an Internet and they can Google how people do it in different places. They want to talk about it, and I have some experience in that because that's what I studied as an anthropologist, child‑rearing.

Dr. Biology:  Back to the evolutionary medicine and the Darwinian pediatrician. Are there misconceptions about the difference between someone who says that they're going to practice with a focus on evolutionary medicine and a traditional pediatrician?

Dr. Paul:  There are. I really had a wake‑up call when I had an interview with the "New Scientist" magazine. I didn't write the headline, of course, but the headline was something like, "Darwinian Pediatrician says Hold the Painkillers."

I generally support that, in the sense that acetaminophen and ibuprofen, millions and millions of doses of that are taken every year, not just in adults, but in children. Those are great medicines when they're called for. My point was that they're used too much. A lot of the things they're used for...

When you get a twisted ankle, say, it hurts, so the pain makes you lay off, and not keep playing that soccer game. It's not all bad for a twisted ankle to hurt. The swelling and the inflammation that occurs when you twist your ankle, those are all part of the immune system and the inflammatory system working to heal that ankle. When you take some of these powerful anti‑inflammatory medicines just willy‑nilly, you can be interfering with all that and causing more harm than good.

I said that very briefly. It was a one‑page article, and I was shocked to see a few days later, after it came out, some comments of people. There was somebody who said, "I had back surgery the other day. Would Dr. Turke, a Darwinian doctor, want me to have had that surgery without anesthesia? Would he have wanted me to not take any painkillers afterward?"

There were other people who said, "Well, I'm glad he's not my pediatrician. That's cruel to hold the painkillers." Well, of course, that's not what I was saying at all. That was a wake‑up call to me because you have to always keep in mind when you're saying things what people will read into it.

All I was saying is that if you're son or daughter twists an ankle in a soccer game, bring her to the sideline. Let her sit down. As long as she's comfortable, let her rest it. If she can keep it comfortable by just taking it easy, that's the best way to let it heal. Let nature take its course.

If a child can't get comfortable, is writhing on the bench because they're in pain, then you go the emergency room and then you may need some painkillers. It's a little bit of a balancing act.

Again, I think it's this term, Darwinian, survival of the fittest. It's this harsh nature, red, and tooth and claw kind of idea. It's not that at all. Darwinian pediatrics, or evolutionary pediatrics, I think is the kindest pediatrics.

Dr. Biology:  I would sum it up as listening to the body.

Dr. Paul:  Yeah, right.

Dr. Biology:  What is it telling you, and paying attention, so that you're not doing what it's telling you not to do.

Dr. Paul:  Exactly.

Dr. Biology:  Sports play such a huge role in our lives. It's not that sports are bad, it's just that big game sports, one of the things that comes to mind are steroids, in particular, the players that are taking steroids, because they have an inflammation, and that way they can go play. The problem is what's happening down the road?

That's another example of taking it too far, trying to avoid what the body is trying to tell you.

Dr. Paul:  Yeah. That's very dangerous. It's funny because I kid with some of my athletes, they're high school kids that come into the office. They're dreaming big. They're thinking they're going to be the next guy signing a contract, or next woman signing a contract for a million dollars, or whatever it is.

If I'm a little suspicious that they might be taking some performance enhancing drugs, or more commonly, if they just want to get back into the game before they heal, and they shouldn't, I'll joke with them and say, "So, what are you getting paid for next Saturday's game? $100,000? $200,000?" "No, no, no. We're getting paid nothing."

If you want to be healthy over the long term, you don't want to be messing with things. You want to let your body heal if it's injured. You certainly don't want to be taking any drugs that over the long run are going to harm you.

Then again, if they're receptive to it, I might point out that if having more steroids in our body, or more testosterone in our body, were good for us overall, we would have evolved to have that. You've got to be very careful with all that stuff.

Dr. Biology:  On "Ask a Biologist" I have a history of asking three questions of all my guests. No one gets out without these three questions. We'll start off.

When did you first know you wanted to be a scientist? In your case, later, where was the particular moment when you knew you wanted to be a physician?

Dr. Paul:  The scientist thing came way earlier. I was born in '53, so there was Sputnik, and then the US Space Program, and all that. When I was about three years old, I wanted to be an astronaut.

Then, after thinking about, "Yeah, that's just kind of like driving a bus," I wanted to be the guy who figures out how rockets work and physics, and all that. That was the first thing that I loved as a kid.

Then I got into dinosaurs. I learned evolution early and became more interested in biology than anything else and evolutionary theory. It wasn't until we had our first child and I met these doctors, Yap is the island we were on, that I realized I really did have a big interest in medicine, pediatrics in particular. I was about 32, I think, when I first decided, "Yeah, maybe I should think about going to medical school."

Dr. Biology:  For our next question, I take this all away from you. You don't get to be a scientist. You don't get to be a physician. The question is what would you be, or would you do?

Dr. Paul:  That's easy. Back when I was making the decision to go to medical school, I had a sign on my door. I think my wife put it up there because we talked about it. It was called "Salsa Farmer." I was going to make organic salsas, locally produced, and so on. This was way ahead of the locavore movement. I would have been a salsa farmer.

Dr. Biology:  Oh, a salsa farmer, interesting. I always say that our farmers, in many ways, they're scientists themselves.

Dr. Paul:  Yes.

Dr. Biology:  The final question is, what advice would you have for a young, budding biologist, or perhaps someone who wants to change careers?

Dr. Paul:  I would say it's never too late. You can always do it. It's a little easier to go to medical school when you're a little younger than 39, but I've known people older than me that have done it. It's never too late to do that.

I would say to young biologists to stay curious. Keep an open mind. Get out there in nature and see things. I would encourage them to think big.

Too many people, down the road, your Department Chair or your 10‑year committee, or your grant panel, NIH or whatever, who's forcing you to be narrow, so while you can be free and think about everything, think about everything.

Dr. Biology:  This leads me into some research I did on you. I found you are writing a book.

Dr. Paul:  Yes.

Dr. Biology:  The title is "Bringing Up Baby: An Evolutionary View of Pediatrics."

Dr. Paul:  Correct.

Dr. Biology:  The first sample chapter is on the Web, so I was able to have it for one of my evening readings. I found it really enjoyable.

Dr. Paul:  Thank you.

Dr. Biology:  I wondered if there was a section that we could have you read. Because we've talked about changing careers, I think there's a place in there that would fit very nicely for that.

Dr. Paul:  Sure. The subsection is, I call it "A Tortuous Journey." It starts off, At age 39, I went to medical school. I got there by a circuitous route, with stops along the way in anthropology, evolutionary biology, and immunology.

The more typical route is straight and narrow and littered with multiple‑choice exams. Exams and more exams, from high school to retirement, they validate every doctor's career. Personally, I don't think much of exams. They conflate factual recall with understanding.

I'm not sure why I was let in, and I hope this book doesn't trigger an investigation. It's quite possible, though, that someone with a name similar to mine got an undeserved rejection letter. I entertain this suspicion because an informant, a doctor friend on the Faculty of one of the two medical schools to which I applied, explained how the selection process had proceeded at his institution.

My Ph.D. in anthropology, the articles I'd published, the classes I'd taught, letters of recommendations from colleagues, none of them mattered. Four thousand applications were plopped on a secretary's desk, and she was instructed to send rejections to all but the top ten percent, judged solely on the basis of undergraduate grade point average and Medical College Aptitude Test score. The remaining applicants were granted interviews, and I was, mysteriously among them.

I left mine feeling as though I'd been hazed. Not the tame kind of hazing that occurs at college fraternities, where mortality rates are fairly low, but more like the hazing that elders have committed on adolescents, throughout much of the world, over much of human evolutionary history.

Anthropologists refer to these affairs as "Rites of passage," which is an overly dignified label for ceremonies that generally include septic circumcisions.

My interviewer was a 60‑something female pediatrician who looked kindly enough but wasn't. Pleasant conversation was not her forte. As an icebreaker, I mentioned that it was a nice day, adding that we nevertheless needed rain. Her response was to ask whether I was interested in medicine or meteorology.

Things deteriorated from there, and I soon found myself scanning the room, hoping not to spy any dirty scalpels. She was unimpressed with my background and quite concerned that my interest in certain theoretical issues would interfere with the care of patients. Her disdain for theory surprised me because she was employed by one of the largest and most highly regarded research hospitals in the country.

Moments later she closed our session with a question, muttering as she got up to leave, "Are you incapable of giving a concise answer to a question?" My quick reply was, "No, which" And I resisted rubbing this in, is pretty concise.

Dr. Biology:  [laughs] Very good. Paul Turke, I want to thank you for visiting with me.

Dr. Paul:  My pleasure.

Dr. Biology:  You've been listening to "Ask A Biologist," and my guest has been Dr. Paul Turke, pediatrician and adjunct clinical faculty member of the Department of Pediatrics and Infectious Diseases at the University of Michigan.

If you want to learn more about the immune system, we have our comic book, "Viral Attack" ready for you at any time – just pop on over. The address is‑attack or you can just Google the words "Viral Attack." We'll be a top result.

The "Ask A Biologist" podcast is produced on the campus of Arizona State University and is recorded in the Grass Roots Studio, housed in the School of Life Sciences, which is an academic unit of the College of Liberal Arts and Sciences.

Remember, even though our program is not broadcast live, you can still send us your questions about biology using our companion website. The address is or you can just Google the words "Ask a biologist." I'm Dr. Biology.

Transcription by CastingWords

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Rebooting the Immune System

Audio editor: CJ Kazilek

Sooty Selection

Discuss ideas of natural selection, play a selection-based game, and take a trip through time to see how scientists of the past figured out just how a trait is passed from a parent to its offspring.

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Zombie Ants

Do zombies really exist? They do... at least in the world of ants. Learn how some ants are made into zombies and find out what ants can do to avoid being zombified.

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A lot of people think we only use a small part of our brains, but this isn't true. While all of your brain is not active every second, most of us use 100% of our brains over the course of a day.

Question From: Tara
Grade Level: 7

Answered By: Patrick McGurrin
Expert’s Title:
Graduate Student

To learn more about how your brain works, visit What's Your Brain Doing?


Have a different answer or more to add to this one? Send it to us.

Images via Wikimedia Commons. Brain with lights by DARPA.

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