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 ...

These parts are either fully developed before or at birth and do not change in size thereafter. In this article, we’ll explore five unique body parts that do not grow after birth, and the ...

If we look across the whole of the mammal branch of the tree of life, we find there are many groups of mammals that have ...

There is a way we can study the separate problem of just why we evolved each of these body parts, but it only works if the feature in question has evolved more than once on separate branches of ...

Dolphins, meanwhile, may have the biggest mammalian testicles of all, making up as much as 4 per cent of their body weight (equivalent to human testicles weighing roughly 3 kilos).