Mammals

There doesn't seem to be much of a gray area. Most people are a hard yes or yard no.

By Meg Sparwath

Sure, opossums eat out of your trashcan, but they're also strange little superheroes.

By Jesslyn Shields

Your favorite cashmere sweater is super-soft and luxurious. It probably cost you an arm and leg, too. Here's why.

By Jamie Allen

A group of researchers in Shennongjia National Nature Reserve discovered that these female monkeys are essentially happy to feed each other's offspring.

By Jamie Allen

Perhaps it's a mating signal. Or meant to confuse owls and other predators. Or maybe it's just for looks.

By Jamie Allen

Elephants make a specific sound to warn each other of nearby humans.

By Loraine Fick

A dolphin doesn't breathe automatically, so during sleep, one side of its brain stays awake to ensure the mammal rises to the surface and breathes.

By Loraine Fick

Penguins stand for months on the coldest ice in the world without their feet freezing, thanks to special blood circulation.

By Loraine Fick

It looks excruciating, and nobody knows exactly why it happens.

By Jesslyn Shields

Before you declare which team you're on, we've got the breakdown on this auditory battle royal.

By Mark Mancini

When we think of big cats in the wild, we most likely think of lions and tigers. But there are so many more amazing wild cats you've probably never even heard of. Here are five.

By Oisin Curran

Do humpback whales get tired of singing the same old song, or do they simply start over when it gets too complicated?

By Jesslyn Shields

A first-of-its-kind study reaffirms why wolves are vital to the health of our ecosystem.

By Michelle Konstantinovsky

The annual bison roundup in South Dakota's Custer State Park is a spectacle full of cowboys, horses and of course wild buffalo, all set against the backdrop of the rolling Black Hills. It's also about as Americana as you can get.

By John Donovan

Scientists have known for a long time that elephants have no sweat glands and keep cool through slinging mud on their skin. But they didn't know what made the skin so wrinkled — until now.

By Nathan Chandler

The old saw about cats being good catchers of rats was finally put to scientific study — and the results were pretty sad.

By Nathan Chandler

A new study found that those spot patterns are not only inherited from mom, they help camouflage baby giraffes in the wild.

By Kristen Hall-Geisler

A new study paints a grave future for the killer whale, all because of the now-banned chemicals polychlopinated biphenyls — PCBs.

By Kristen Hall-Geisler

It's a natural phenomenon known as a 'squirrel king.' But what's the deal and why do squirrels get tangled up?

By Jamie Allen

A dolphin named Billie learned a dolphin-show trick from some captive dolphins, taught her wild friends how to do it and started a fad.

By Jesslyn Shields

The Indian giant squirrel is covered in flamboyant colors like orange, black and bright purple. But why?

By Jamie Allen

It used to be assumed that African bush elephants avoided the sound of an angry bee hive. Now researchers believe they have receptors to detect a bee's alarm pheromones.

By Jesslyn Shields

The Humboldt marten was thought to be extinct until it was rediscovered in 1996. Now it is threatened again.

By Jesslyn Shields

Breaking news: Dolphins and porpoises don't actually look very much alike.

By Jesslyn Shields

Once a week or so, sloths climb down from their trees and poop on the ground. It feels so good, they do a little dance. But this time of pleasure is also a time of peril.

By Alia Hoyt