Bonobos and sex symmetry and maybe us

Bonobos are the closest species to humans, looking similar to Chimps but with a very different social structure. Humans share many traits with bonobos, perhaps more than we always admit.

If you put a male and female bonobo together in captivity, then the slightly larger male will dominate and have preferential access to food and other resources. However if you put a male in with two females then the females will cooperate and dominate. That's how it was explained, probably in one of Frans de Waal's excellent books. But just recently I had a think about this.

There is a symmetry between the sexes which works like this: If one sex has some characteristic that is advantageous, then the other sex will have a significant reaction to this. Commonly they will want to evaluate how well individuals perform, but also they will adjust their behaviour to fit in.

So I wonder if it is really necessary for the two females to explicitly cooperate to dominate the male. It seems more likely the male has a different response when there are two females, based on the knowledge that they will cooperate.

I suspect humans are like that. If there are two or more women together, then men are inclined to behave themselves. However humans aren't like bonobos:

• Humans pair up to raise babies. Women prefer not to share a good husband if they can find one.
• Humans have mostly solved the problem of safe relations between one man and one woman. The real estate industry says that 90% of real estate decisions are taken by the woman in the relationship. I think this extends to all aspects of family life. In the main women dominate that part of life and most men are happy with that.

Most young men are happy to find a nice partner who will look after family life and tell them what to do. However there is a limited supply of such men. Rather than giving up, I think women should also be open to setting up a family situation with another woman (or even more), and keeping male company to well controlled situations where, in particular, more than one woman is present.

There are many cultures in which the male and female worlds are significantly separated so I think this sort of arrangement is quite compatible with human nature. Indeed I think many young women today bring men in to their bed in their parents' home. This is a safe way to start on adult life, and if babies arrive then grandparents are usually delighted to help with that.