New research challenges the one-level view of evolution, showing natural selection works on individuals and groups together.

Natural selection is the process by which some organisms in a population survive and reproduce, while others do not, based on their bodies and behaviour. It is one of the processes by which species ...

The common view of natural selection is based solely on the individual: A trait allows an organism to out-compete its rivals and is thus passed down to its offspring. To suggest otherwise can provoke ...

The Indigenous peoples of the Bolivian highlands are survivors. For thousands of years they have lived at altitudes of more than two miles, where oxygen is about 35 percent lower than at sea level.

Why does the peacock have such an elaborate tail? This cumbersome trait significantly decreases the male's chances of survival. It only exists because it confers an advantage to its bearer in the form ...