Tim Tyler  wrote in
news:cnftq2$1a2g$1{at}darwin.ediacara.org: 

> Dan Kim  wrote or quoted:
> 
>> A while ago a friend of mine suggested homosexuality is a natural
>> form of population control.  Now having taken a first year course on
>> evolution, I would develop that to say that homosexuality may be a
>> density dependent limiting factor on populations.  Some weak
>> empiracal evidence may be the rise of homosexuality and its
>> acceptance into western society, now as the human population grows
>> exponentially in this post-industrial information age. I am not
>> trying to say homosexuality is a "disease", nor am I trying to be
>> disrespectful. Afterall heterosexuality was also an evolutionary 
>> development (from asexual species). 
>> 
>> I am wondering if anyone has ever proposed this formally, such as in 
>> academic research?
> 
> "Can't Homosexuality Be Seen as Population Control?"
> 
>  - http://www.probe.org/docs/e-homosex13.html
> 
> ...explains why this theory is not very orthodox as follows:
> 
> ``Things such as "population control," as you suggest, require a 
>   cooperative spirit (technically referred to as group selection) that
>   is normally considered outside direct genetic influence and is
>   therefore rejected by most evolutionary biologists.''


It may be possible for deme level selection (group selection) to evolve 
density dependent population controls. In order for this to happen you 
would presumably need a rapidly reproducing species that frequently 
invades isolated habitat patches, and you would need the density 
dependent control to significantly reduce reproductive rates at high 
densities. Rats are the obvious example. Humans may frequently invade 
isolated habitat patches, but do not reproduce all that rapidly, and 
homosexuality does not appear at high enough rates to be effective in 
preventing population crashes.
 

(snip other good information provided by Tim on alternative explanations)


Yours,

Bill Morse
---
þ RIMEGate(tm)/RGXPost V1.14 at BBSWORLD * Info{at}bbsworld.com

---
 * RIMEGate(tm)V10.2áÿ* RelayNet(tm) NNTP Gateway * MoonDog BBS
 * RgateImp.MoonDog.BBS at 11/18/04 7:39:03 AM