Socially-learned cultural behaviour thought to be unique to humans is also found among chimpanzees colonies, scientists at the University of Liverpool have found.

In the September issue of The American Naturalist, Juan Carranza (Biology and Ethology Unit, University of Extremadura, Spain) and Javier Pérez-Barberнa (Macaulay Institute, United Kingdom) offer a new explanation for why males of ungulate species subjected to intense competition are born with lower survival expectancies than females.