A side view illustration of the internal female reproductive system
Written by: 
Risa Aria Schnebly
Our biological sex affects the way we look in some obvious ways, like deciding what body parts we are born with. But, it also has effects on a range of other sexual traits that you might not expect.
A cartoon house with wastewater going from the sink into the sewer
Written by: 
Challie Facemire
Most of us don’t think of the sewers as an exciting place. But these and other waterways are where Rolf Halden is finding and solving many mysteries.
A picture of a wolf looking toward the camera, image by USFWS
Written by: 
Chelsea Brzezinksi
In Yellowstone National Park, winters are getting shorter and there is less food for scavengers. That’s bad news for scavengers like bears, but could wolves help?
An image of ovaries in a person with PCOS. The image features an external look at a bumpy ovary attached to the rest of the female reproductive system, as well as a close-up, detailed look at the cysts within the ovary.
Written by: 
Emily Santora
Estrogen and testosterone are two hormones that cause puberty. But what happens when the body doesn’t produce the amounts of hormones that it usually does?
A woman clutching her abdomen, experiencing period cramps.
Written by: 
Emily Santora
Sometimes things don’t work as you expect them to, including periods. Learn more about what causes some girls to have irregular or painful periods.
A brown howler monkey on a tree branch
Written by: 
Kathryn Michelle Benavidez Westrich
How do seeds travel if they do not have legs to carry them? We can find one answer in primate poop.
The front of a great white shark, swimming through the water
Written by: 
Chelsea Brzezinski
In Peru, how humans feel and what they know and do about sharks can have big consequences. How do human beliefs impact shark conservation?
An intersex pride flag, showing a purple circle on a yellow background
Written by: 
Risa Aria Schnebly and Riley McInnis
You might think that people can be born only as either males or females. In fact, lots of people are born with a blend of male and female traits. We call this being “intersex,” and it happens more often than you may think.
Male sex chromosomes, XY
Written by: 
Risa Aria Schnebly
Our biological sex determines a lot about the way our bodies look and function. But what determines our biological sex?
Illustrated image of a uterus
Written by: 
Emily Santora
What happens when a person wants to have a baby, but after years of trying, it just doesn’t happen? A lot of people want to become pregnant, but let’s learn about what may prevent pregnancy.

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