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 ...

Tusks are a striking feature of many animals -- elephants, hippos, warthogs, walruses -- and are often sought-after by humans. But no birds, fish or reptiles today sport this extreme and ever-growing ...

A new book dives into the evolutionary history of mammals. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. Shortly after dinosaurs got their ...

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.

Modern mammals are known for their big brains. But new analyses of mammal skulls from creatures that lived shortly after the dinosaur mass extinction show that those brains weren’t always a foregone ...

Every spring I bring my students to the desert of northwestern New Mexico, just north of Chaco Canyon, where the ancestral Pueblo people built a great city out of rocks a millennium ago. As we hike ...

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Breakthroughs, discoveries, and DIY tips sent every weekday. Terms of Service and Privacy Policy. The idea that most biologically male members of a species are ...

Rachael has a degree in Zoology from the University of Southampton, and specializes in animal behavior, evolution, palaeontology, and the environment.View full profile Rachael has a degree in Zoology ...