Human evolution is often told as a tidy story of adaptation, yet some of our most familiar body parts still defy ...

The human body is a machine whose many parts – from the microscopic details of our cells to our limbs, eyes, liver and brain – have been assembled in fits and starts over the four billion years of our ...

The authors do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their ...