How Do We Know When Our Ancestors Lost Their Tails?

Our primate progenitors had bodies a lot like those of modern monkeys and spent tens of millions of years living in trees. From them we inherited our versatile hands, amazing vision and capable brains — but also some less beneficial traits, including our bad backs and terrible sense of smell.

A key moment in our evolutionary saga occurred 200 million years ago, when the ferocious reptile-like animals that roamed the Earth were in the process of evolving into shrew-like mammals. But our reptilian ancestors left their mark on many parts of the human body, including our skin, teeth and ears.

Our arms, legs, necks and lungs were bequeathed to us by a fish that lumbered onto land some 375 million years ago. The genetic legacy of this creature can be seen today in our own DNA, including the genes used to build our hands and limbs.