Homosexual behavior in apes can help them become more civilized because it
can help them communicate more freely. Researchers have found that
homosexual behavior is common in apes. They also speculate that
homosexuality is a factor in the survival of the species.

Homosexual behavior may have a civilizing influence among the apes, if not
among human beings

People who work with primates are used to apes' planting affectionate pecks
on their lips. But imagine the surprise of a San Diego zookeeper, unfamiliar
with a newly arrived species known as the bonobo, when the animal gently
slid its tongue into the zookeeper's mouth. The only thing more surprising
than the French kiss was that the bonobo, like the zookeeper, was male.