According to Desmond Morris...
[I know, I know: that's an old reference. Lotta research since then.]
The most accurate predictor for whether animals exhibit homosexuality is how unnaturally crowded are their living conditions. If it holds up (I've yet to hear it discredited - though I only follow bio news in a spotty fashion) then homosexuality will be a normal and natural response to our modern lifestyle. Humans were designed to live in widly separated small tribes.
