Since male homosexuals, by definition, leave fewer offspring than male heterosexuals, the genetic basis for ‘gayness’ should rapidly be eliminated from any breeding population. Since the incidence of male homosexuality nevertheless seems stable and significant, around 5%, there appears to be some kind of paradox here.
It has been suggested that gay men make better uncles than straight men, thereby facilitating straightforward kin selection. But there is little evidence for this. So here is my proposal.
1. Gay men tend to exhibit more relational competences than straight men. Evidence: the prevalence of gay men in service professions; the discussions about the ‘feminised brain’ of male homosexuals.
2. In the environment of evolutionary adaptiveness (EEA), the foundational basis of group dominance in primate species, including man, is typically aggression. This comes down to the leader’s ability to physically dominate others by violence and intimidation.
3. Leadership by the physically most intimidating is counter-productive where intelligence is at a premium, as in human evolution. The ‘wisdom of crowds’ applies. There is a requirement to negotiate points of view, insights and buy-in across the group.
4. Gay men bring particular interpersonal skills to group problem-solving and group cohesion. Groups with such functions out-perform groups which operate only on a hierarchy of fear, where the powerful leader cannot be contradicted. Note that due to the sexual division of labour, women cannot perform these functions.
5. Since all competing human groups in the EEA were extended kin groups, genes for male homosexuality had some use after all and so were conserved.
In fact, in today’s more complex societies exactly the same points apply.
Experimentally testing this idea would involve comparing problem-solving competences (in novel environments) for stable groups contrasted in temperament as typically found along the straight-gay axis. The prediction would be that maximal effectiveness would be exhibited by groups in the straight-gay ratio of around 19:1. An alternative would be ethnographic analysis of groups looking at roles played by gay men.
Notes
1. Due again to the sexual division of labour, it seems this analysis is not at all applicable to female homosexuality.
2. A possible difficulty with this suggestion is that there are plenty of men around who seem adept at diplomatic skills without being gay. The term 'metrosexual' seems to have been coined for this group! However, perhaps there is a continuum effect, and gay men are simply the most effective in these kinds of roles, sufficient to offset their lack of direct 'fitness'.