First, no one is sure why we, or any other animal, dream. During the past century, however, scientists have made significant progress in understanding the factors that influence sleep and dreaming.

National Geographic estimates there are between 50 billion and 430 billion birds populating the planet, outnumbering humans by up to approximately 50 times. Spread across 9,700 species, according to ...

A new book, The Rise and Reign of the Mammals by paleontologist Steve Brusatte, explores how our ancestors emerged, evolved, and took over the world. Reading time 10 minutes Deep time is a headache.

They are the most successful mammals that you probably haven’t heard of. Multituberculates were squirrel-like mammals that first evolved in the Jurassic, about 170 million years ago, and survived ...

From its long, flexible trunk to its loud trumpeting sounds, there’s a lot to admire about an elephant. But how much do you know about these massive creatures? Where do they live? How big can they get ...