institutionalised celibacy

What is the role of institutionalised celibacy in the emergence of societies with large population size?

1. Every human group - at least after the big expansion phase - needs to have some form of population control. Non-contraception, this can take varied forms: abandoning new born babies (before the costly emotional attachment), head hunting pre-puberty girls (the number of women being the limiting factor in child births), frequent wars between neighbouring villages (say, triggered by 'the curse' that the other village/tribe had put on the crops and thus resulted in bad harvest and the expectation of the coming shortage), human sacrifice rituals (often it is young women who are deemed to be witches to be killed, although sometimes it is young men), or removing a section of the population from procreation by some form of permanent or temporal ban of sexual activity.

2. It seems that there might be significant difference among the above forms of population control, in terms of cost to the society. This cost might vary a lot along population size. That is, a set of small villages with mostly separate social networks could have a headhunting tradition without it being too disruptive to the stability of their societies. The destabilisation effect would be more costly in a large society where texture of the social network is more evenly distributed.

3. It seems that out of all the possible non-contraception forms of population control, the institutionalised celibacy stands out as being ideal for large small-world societies. You reduce the number of children from a part of the population, without the destabilising effect that would come from killing them. At the same time, you can use them in one of the many non-family functions that large societies give rise to.

4. Institutionalisation of this merge between celibacy and societal functions for a group of people provides temporal stability to the function, and could also reduce the cost of it.

5. Some form of institutionalised celibacy evolved in many different cultures independently, and it seems that the time of the appearance of these institutions coincided with population expansion. If this was to stand, it would be a great support to the above argument.

I am not sure what the consequence would be for the global society. Maybe there is not much, given the contraception technology becoming dominant. In this case, there would always remain some cultural remnants of the different forms of the celibacy institutions, perhaps getting occasionally stronger in times of resource shortage, but gradually eroding. Or perhaps there will be a new wave and form of it, maybe along some global green political issue -- although it is unlikely to be 'instinctive' as even if we subscribed to group evolution, any form of genetic evolution would be impossible for the relevant groups size.

What do you think?