A clip from a National Geographic programme ‘Wild Sex’ showing that humans are not the only ones to form relationships with their own gender.
Homosexuality has been documented in more than 450 species of mammals, birds, reptiles, insects and other animals.
A comprehensive book on the subject, collating years of research, is ‘Biological Exuberance’ by Bruce Bagemihl.
Also see Evolution’s Rainbow: Diversity, Gender, and Sexuality in Nature and People by Joan Roughgarden at
and recently: “Homosexual behaviour widespread in animals according to new study”