Human evolution theory utilizing concepts of neoteny & female sexual selection
An etiology of neuropsychological disorders such as autism and dyslexia, and the origin of left handedness.
"But although silver foxes had been bred in captivity since 1892 on fur farms, and although some selective breeding for traits such as fertility and high fur quality had been practiced, the animals were not domesticated in any strict sense. They retained all of the essential characteristics of their wild counterparts. They molted and came into heat in a strict seasonal cycle, as in the wild; their behavior toward humans was no different than that of a wild fox raised in captivity. So Belyaev decided to try an experiment. He would rigorously select animals applying but a single criterion: Those animals that showed consistently tame behavior toward humans would be kept; those that did not would be eliminated from the breeding program. Within five generations changes were already apparent. By 1979, twenty years into the experiment, the results were astonishing. His tame-selected foxes were not just tame; they acted for all the world like domestic dogs. They approached familiar persons and licked their hands and faces. They barked like dogs. They even sought the attention of strangers by whinning and wagging their tails. Their annual molting cycle was disrupted, and the females began to come into heat twice a year, like dogs, and unlike both foxes and wolves. they also developed some physical characteristics of young foxes, such as drooping ears, and some of the variations in traits seen in other domesticated animals, such as piebald coat coloration. Belyaev in an astonishingly short time produced not just one new trait, but a whole package of new characteristics. What he had done, by selecting for nothing more than tameness, was to tap into the same powerful evolutionary tool that nature had employed as a solution to the successive ecological catastrophes of the ice ages: neoteny." (Budiansky (1992) The Covenant of the Wild. Morrow: New York pp. 96-7)