Female grizzly bears, for instance, form couples and help raise each other's cubs.
Most male orcas, dolphins, Amazon botos, whales and other cetaceans masturbate each other.
Pretty much all female langurs are bisexual.
Male flamingo couples incubate, hatch and successfully raise foster chicks.
Coupled male Humboldt penguins on the other hand never acquire eggs to hatch together.
Male giraffes love "necking" with each other.
Transgendered deer are called "velvet horns."
Male bighorns are so into each other that females needs to pretend to be male to attract a mate.
Some elephant seals are transvestites, trying to act and look like females.
And of course female hyenas can mount each other.
Not to mention what all that waterfowl, shore birds, perching birds and songbirds get up to.
Nature has "heterosexual animals that never reproduce, homosexual animals that regularly procreate -- breeding and sexual orientation often combine in unexpected and paradoxical ways." Dr. Bagemihl's book points to a different way of seeing the natural world, and "perceiving broader patterns in nature and human society."