Thursday, November 5, 2009

Scott and Fuller's 1965 Treatise Still a Gold Mine

In reading modern authors on dog evolution and behavior, such as Coppinger and Miklosi, one finds many references to a book published long before modern genome technologies, Genetics and the Social Behavior of the Dog, by John Paul Scott and John L. Fuller (U. Chicago Press, frequently reprinted). I had avoided reading the book because I feared that its relative antiquity would mean that I would constantly be reminded how far science has come in understanding the genetics of dogs. To the contrary, once I picked the book up, I found it hard to put down. The authors may not have had all the modern tools of molecular biology, but their discoveries are phenomenal and every page is full of valuable observations, some of which have never been stated better. It’s such a brilliant work that I have no doubt I will be reading it again soon. Just two passages will be quoted here. The first concerns the evolution of dogs:

Adaptive radiation on a smaller scale [i.e., smaller than what happened with mammals once reptiles (dinosaurs) had been eliminated as major rivals] seems to have taken place soon after the dog became domesticated. Within the various human societies, dogs found a whole new habitat. The dog, as one of the first domestic animals, was a remarkable social invention, both for protection and as an aid to hunting, and every tribe must have wanted to get hold of one. In this way dogs spread rapidly over the world, differentiating as they moved, and so produced the southern short-haired varieties like the dingo and, at the opposite extreme of their range, the northern Eskimo dogs which are almost like wolves. A further multiplication of habitats was provided when the herd animals were domesticated. Now dogs were needed to protect those herds against their own close relatives, the wolves, which found the domestic beasts easy prey.

Then there’s the following on the overbreeding of champions, an issue I’ve discussed here before:

The desirability of multiple standards makes the practice of breeding a champion to a large number of females within a breed a questionable one. Almost every animal carries some sort of injurious recessive genes, and this practice insures that they will be spread throughout the whole breed, with resulting disappointment as the descendants of these champions are eventually bred together and the recessive traits begin to show up in large numbers. The breed objectives should not be the development of a single, fixed type—something which is only possible by strict inbreeding—but rather for the development of a population varying within desirable limits and within which new and more valuable combinations of genes will always be possible.

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