New research is cutting male mammals down to size. While we may think of hulking elephant seal bulls or huge stags, these males appear to be the exception, rather than the rule. A new analysis of more ...

Soil is a mixture of organic and mineral matter, as well as water, air, and microorganisms. The minerals come mostly from bedrock, which is broken down into tiny particles over many years by physical, ...

Read a National Geographic magazine article about the rise of mammals, and get information, facts, and more about the evolution of mammals.

Last week Chicago’s Field Museum of Natural History placed on exhibition a unique skeleton: that of Titanoides faberi, earliest mammal of its size known to exist on Earth. Like birds, mammals are ...

Over the past 125,000 years, the average size of mammals on the Earth has shrunk. And humans are to blame. That's the conclusion of a new study of the fossil record by paleo-biologist Felisa Smith of ...