The ups and downs of a life less social

Breeding in large, cooperative groups allows the costs of reproduction to be shared amongst individuals. This has enabled organisms to live in places that would otherwise be uninhabitable. However, a ubiquitous feature of animal societies is that breeding groups vary markedly in their size and composition. Why, given the benefits of cooperation, do large groups only sometimes emerge? Here I present a series of experiments on the worlds largest bird, the ostrich, where the answer to this question involves a tale of sex, cheating and cooperation in the struggle to reproduce in some of the hottest places on earth.