The notion of species may underpin almost every aspect of biology, yet scientists can’t agree on a single definition. Time ...

This article was originally featured on Undark. For centuries, taxonomists have cataloged every living thing they could find. Expeditions have traveled the globe, searching for unknown species; ...

A species is a group of living organisms that are all broadly similar and can, at least in principle, breed with one another. This seems straightforward enough, but the word “species” is actually ...