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AWalk in the Park

Time Machines of the Southwest

show/hide words to know

  • Caves of Lascaux: a series of caves in Southern France that hold a collection of prehistoric cave paintings... more
  • Descendant: a plant or animal that descended from a particular group or family. Everyone is a descendant of their parents, grandparents, and great grandparents.
  • Petroglyph: a rock drawing made by pecking or chipping away at the outer surface of a rock face... more.
  • Pictograph: a picture or symbol. Pictographs are also called pictograms and have been found in Egypt and Mesopotamia that are thousands of years old.

Time Machines of the Southwest

You may not know it, but there are time machines waiting for you. All it takes is knowing where to look. So if you have dreams of transporting back in time to visit distant places or a desire to meet unknown cultures and deciphering lost languages, there is place you have to visit. It is the desert southwest.

Petroglyph in South Mountain Park ArizonaPetroglyph in South Mountain Park ArizonaPetroglyph in South Mountain Park Arizona

Petroglyphs in South Mountain Park Arizona. Click on any of the photographs to enlarge and learn more about the images. You click on the player below to listen to rangers Liz Smith and Justin Olson talk about the petroglyphs in South Mountain Park. You can also or get the mp3 file here.

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The time machines are drawings on rocks made thousands of years ago. Petroglyphs and pictographs are their common name and they can be found not only in the desert southwest, but almost anywhere in the world. They are carved or etchings into the surface of rocks. Much of the rock found around Phoenix has a dark surface called a “Patina”. Once it has been carved or chipped away, the lighter color of the rock is revealed. This makes the rock art stand out like a prehistoric neon sign. It is also why petroglyphs have lasted for such a long time.

Unlike petroglyphs, pictographs are prehistoric paintings applied right on the rocks surface. These are much like painting on a canvas. Usually the pictographs we see are painted onto lighter colored rocks, so the bright paint can be seen. Just like painting on a white canvas. There are a group of pictographs found in the caves in Lascaux France that are estimated to be more than 17,000 years old.

Petroglyphs in South Mountain ParkPetroglyphs in South Mountain ParkPetroglyphs in South Mountain Park
Petroglyphs in South Mountain Park Arizona. Click on any of the photographs to enlarge and learn more about the images.


So you might be wondering why they are called time machines if you really don't travel back in time? True, you are not going to step into a science fiction machine to transport back thousands of years. What these rock art images allow you to do is see what the desert southwest might have been like long ago. The fading images provide clues into who used to thrive where we live now, what they used to eat, how they survived, what the weather might have been like and what was important to their families and culture. Best of all these time machines don't require electricity or any other power other than the power of your imagination.

If you look carefully when hiking in about any of the parks in the desert southwest you are likely to see a range of designs and symbols. There are animals, insects, people, geometric designs, spirit beings and astronomical calendars.  Many of the rock art forms may seem unusual to us, but if we were to imagine traveling to another planet in space, we may possibly see new life forms or speak with other cultures that live very differently from the way we do today.

Petroglyphs in South Mountain ParkPetroglyphs in South Mountain ParkPetroglyphs in South Mountain Park
Petroglyphs in South Mountain Park Arizona. Click on any of the photographs to enlarge and learn more about the images.


Since the people who made these inscriptions are no longer living with us, we can only speak with the descendants of these people to try and make sense of their meaning. Rock art is our link with people of prehistory, and a glimpse into the distant past. What do you think the meaning is of these incredible works of art? As you hike and discover these images, imagine the artist at work creating these symbols that have lasted a thousand years.

Paper and pencil petroglyph activityWhen you return home you can make up your own petroglyph game. Take out a sheet of paper and see if you can draw similar images as the ones you saw during your hike or from the collection of images on this page. Next see if you can make your own symbols to tell a story. How many or few would you need? Then share them with friends and family to see if they can figure out what you are communicating.

Entrance sign to South Mountain Park. Arizona

A short drive from downtown Phonenix, South Mountain Park offers a living outdoor museum perfect for exploring.

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Entrance sign to South Mountain Park. Arizona

A short drive from downtown Phonenix, South Mountain Park offers a living outdoor museum perfect for exploring.

Share to Google Classroom

Be part of Ask A Biologist

by volunteering, or simply sending us feedback on the site. Scientists, teachers, writers, illustrators, and translators are all important to the program. If you are interested in helping with the website we have a Volunteer page to get the process started.