In the mid-20th century, psychologist Harry Harlow conducted some of the most disturbing animal experiments ever approved.

A mother drill monkey inspects the corpse of her infant son A monkey from a zoo in Europe was recently seen carrying around her baby's corpse for several days after it died. Then she devoured her own ...

Between the Old World, which includes Africa and Asia, and the New World, which includes Mexico and Central and South America, there are well over 200 monkey species. Yet, nearly all species of baby ...