Joy—fleeting woo-hoo moments like "catching the perfect wave"—is felt by many diverse animals, and researchers want to know how they express it in various situations and why.

For almost two decades, scientists have debated whether sponges or comb jellies are the first animal lineage. Now some are ...

Nature is full of surprises, but few are as fascinating as hybrid animals, creatures born from crossing two different species ...

Scientists have long focused on quantifying fear and other negative emotions in animals. Now they’re trying to measure ...

Small mammals are early warning systems for environmental damage, but many species look almost identical, making them hard to track. Scientists have developed a new footprint-based method that can ...

A new study suggests humans belong in an elite “league of monogamy,” ranking closer to beavers and meerkats than to ...

A cow in Austria has made headlines for demonstrating flexible tool use, challenging assumptions about animal intelligence.

A popular idea suggests a link between big brains and a rich social life, but octopuses don't fit the pattern, which suggests ...

Abigail Morris first visited the Peruvian Amazon when she was 6 years old. Now, as a Ph.D. candidate in the Animal Behavior ...

At first glance, this mammal looks like a horse gone terribly wrong. But, in reality, Chalicotherium is far from a botched ...

Turtles today are often slow-moving, modestly sized creatures, but their ancient relatives were quite different. Long before ...

Have you ever been to a zoo and thought that the animals looked sad? Or perhaps you’ve visited a wildlife park and felt that ...