Gleichgeschlechtliches Sexualverhalten wurde bei Dutzenden Primatenarten beobachtet, was auf einen evolutionären Ursprung schließen lässt

Some years ago I read a book [‚Biological Exuberance‘ ](https://us.macmillan.com/books/9780312253776/biologicalexuberance/) which approached this subject from the point of view of evolutionary psychology in over 450 animal species. It was a great discussion of one aspect of evolutionary psychology though I suppose that with a publication date of 1999 there is a lot more that could be said today. The present price, however, is not for those who suffer from high blood pressure.