> [!cite] > Bagemihl, Bruce. *Biological Exuberance: Animal Homosexuality and Natural Diversity*. 1999; St. Martin’s Press, 2012. > [!abstract] > Homosexuality in its myriad forms has been scientifically documented in more than 450 species of mammals, birds, reptiles, insects, and other animals worldwide. Biological Exuberance is the first comprehensive account of the subject, bringing together accurate, accessible, and nonsensationalized information. Drawing upon a rich body of zoological research spanning more than two centuries, Bagemihl shows that animals engage in all types of nonreproductive sexual behavior. Sexual and gender expression in the animal world displays exuberant variety, including same-sex courtship, pair-bonding, sex, and co-parenting—even instances of lifelong homosexual bonding in species that do not have lifelong heterosexual bonding, ---