http://www.joe-perez.com/2006/01/promiscuity-testicle-size-and-brain.html
"Studies of bats and other mammals have found that the average brain size is 36% bigger among monogamous males than promiscuous males researchers say. In bat species with promiscuous females, the male's body has been shown to use more of its energy to enhance the testes, costing the males the energy needed to further develop their brains. Promiscuity is also associated with big testicles among chimpanzees, whereas dominant gorillas with exclusive access to a harem of females are known to have small testicles.
"The implication is that males of some species make a trade-off between brain power and sex appeal. In promiscuous species, where there is heightened competition for male sexual success males are more likely to choose balls over brains compared to non-promiscuous species".
Joe Perez (who put the above on his site) is speculating about "choosing" balls over brains, but I don't think choice comes into it because it must be genetic and more energy is going into the development of the testicles whether the individual wants it to or not.
In chimps it is not just testicle size that is bigger but penis size too. This is thought to be for two reasons, firstly that the females are sexually selecting them and secondly that (as well as needing extra sperm to compete in impregnating females - hence the size of testicles) the penis works as a plunger to try and remove the previous sperm before it reaches the egg and deposite his own. Natural selection favours this development in the promiscuous species but not in the monogamous.
http://www.neoteny.org/a/testiclesize.html
What do you all think about the idea of the trade off between brain size and sexual activity? What are your views on promiscuity in general and how it affects human society?
The above is just one interesting aspect of the subject of promiscuity.
"Studies of bats and other mammals have found that the average brain size is 36% bigger among monogamous males than promiscuous males researchers say. In bat species with promiscuous females, the male's body has been shown to use more of its energy to enhance the testes, costing the males the energy needed to further develop their brains. Promiscuity is also associated with big testicles among chimpanzees, whereas dominant gorillas with exclusive access to a harem of females are known to have small testicles.
"The implication is that males of some species make a trade-off between brain power and sex appeal. In promiscuous species, where there is heightened competition for male sexual success males are more likely to choose balls over brains compared to non-promiscuous species".
Joe Perez (who put the above on his site) is speculating about "choosing" balls over brains, but I don't think choice comes into it because it must be genetic and more energy is going into the development of the testicles whether the individual wants it to or not.
In chimps it is not just testicle size that is bigger but penis size too. This is thought to be for two reasons, firstly that the females are sexually selecting them and secondly that (as well as needing extra sperm to compete in impregnating females - hence the size of testicles) the penis works as a plunger to try and remove the previous sperm before it reaches the egg and deposite his own. Natural selection favours this development in the promiscuous species but not in the monogamous.
http://www.neoteny.org/a/testiclesize.html
What do you all think about the idea of the trade off between brain size and sexual activity? What are your views on promiscuity in general and how it affects human society?
The above is just one interesting aspect of the subject of promiscuity.