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 ...

Dominant male lemurs flexibly grow their testicles when other males are around, putting them in a better position to successfully mate. In many species, dominant males have larger testes than ...

Undescended testicles (UT), which is used synonymously with the term cryptorchidism, is characterized as the failure of either one or both testes and their associated structures to descend during ...