Birds can learn to recognize fast and flashy butterflies they've failed to catch in the past—as well as similar-looking species—research finds.

The largest and smallest Caribbean mammals have been the most vulnerable to extinction, a finding that may lead to ways to prevent future biodiversity loss.

Despite our unusual propensity for sweating, our bodies require less water than those of our fellow primates, research finds. Could our noses be why?

Cracking the mystery of how squids evolved to control their skin's color and brightness could lead to color-shifting camouflage.

The fossil hand of a 4.4 million-year-old skeleton could offer clues to how early humans moved and began to walk upright.

Researchers thought Pacific and Caribbean crocodile populations in Panama would be different species. Their genes tell a different story, one about the Ice Age.

3D imaging technology used to analyze nearly 600,000 limb poses of modern birds and alligators offers clues to how dinosaurs moved from place to place.

Scientists decked out bugs with body armor and watched them face off in wrestling matches. The experiements highlight the evolution of natural weapons.

The venom from three kinds of spitting cobra shows that the poison evolved to be particularly painful, but not as a hunting tool. It's actually for defense.

Imaging the skull of the fish species Tiktaalik roseae clarifies how they ate. Those findings clarify tetrapod transition from water to land.