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 ...

How do new species form? Like most areas of Evolutionary Biology, research related to the formation of new species - 'speciation ' - is rich in historical and current debate. Here, we review both ...

Darwin's great insight, and the unifying principle of biology today, is that all species are related to one another like sisters, cousins, and distant kin in a vast family tree of life.