Homosexuality

[Jenny A]

Evolution doesn't mess around.  If something is detrimental to a specie's continuance it disappears within a few generations.  At least that's how natural selection works.  Cultural selection, which seems to take precedence in human reproduction, is too new - it's conceivable that we might select ourselves out of existence.  That's doubtful though.

Homosexuality shows up in many species.  This makes sense in a way as there are usually a batch of surplus males hanging around.  Yes I know there aren't usually batches of surplus females waiting around, except in wolves and hyenas, but brain wiring is brain wiring.  Baboons have a matriarchal culture, with, I imagine, the grooming getting a little heavy on occasion.  I don't however, remember reading of female homosexuality in other species.  This might be because guys do most of the writing.  Neanderthals might have split into groups based on sex and only interacted on rare and all too brief occasions.  There is some evidence of this.  If they did it homo Sapiens might have lived in a similar fashion until recent times.  This allows room for all kinds of sexual variation to be hardwired into the gene pool and persist.

I like the Rich Uncle Hypothesis.  An extra spear chucker on the old homestead - available for relatively low overhead - would be very handy.  One would think a small desert tribe would see the economic and survival benefit of such an arrangement.  Just imagine how the book might read if they had.

I think you are being a little simplistic here. Natural selection chooses among inherited traits based upon successful reproduction into future generations.   But genes are rather more complicated than single traits. One useful trait may be linked genetically to another detrimental one. If the useful trait is more valuable than the detrimental one is detrimental,  the detrimental one will persist.  Additionally, traits which promote the fortunes of relatives may persist, even if they don't directly increase the reproduction of the individual.  Homosexuality might be such a trait.

And remember that there are environmental traits which are not affected directly by natural selection of genes such as fetal alcohol syndrome.  Some drugs are known to increase Homosexuality progeny.  

Finally,  traits are more and less useful in different environments.  There really aren't good and bad traits, only more and less useful in certain environments.