EVOLUTION

Pucker your mouth when you eat something sour? You're not the only one.

Why Do We Make Weird Faces When We Taste Something Sour?

If you can't resist puckering your mouth when you lick a lemon or snack on Sour Patch Kids, you can thank evolution.

Meet the Sea Slug With the Disposable Penis

Fans of '90s alternative music may recall King Missile's big single, "Detachable Penis." While the song may have been silly, it turns out than in the animal world, the idea isn't all that bizarre—at least not to the sea slug Chromodoris reticulata.

Chimpanzees hang out in Gombe National Park.

9 Amazing Facts About Chimpanzees

Chimpanzees share about 98 percent of their genes with humans, but you wouldn't want to invite this side of the family over for dinner.

11 Fascinating Facts About Chipmunks

What do chipmunks eat? Baby birds, occasionally. Do chipmunks hibernate? Yes, but not like bears do.

An illustration of a woolly mammoth, blissfully unaware of its species impending doom.

20 Cool Facts About the Ice Age

How many ice ages have there been so far? The same number of ‘Ice Age’ movies that have been released. (Five.)

A replica of the Laetoli footprints discovered in Laetoli, Tanzania; The original footprints were dated to 3.6 million years ago.

9 Fascinating Discoveries that Changed Our Understanding of Human Evolution

Scientists have uncovered ancient fossils, prehistoric artwork, and other clues to human evolution. Here are nine of the most revealing discoveries that have changed our understanding of our early ancestors—and ourselves.

This illustration is not endorsed by science.

Common Misconceptions About Evolution

The phrases ‘survival of the fittest’ and ‘natural selection’ really only scratch the surface of Charles Darwin’s theory of evolution.