The PBS series NATURE recently aired two programs about the evolution of dogs. You can watch the first one here:Rise of the Dog
The show discussed a theory about the domestication process that transformed wolves into dogs. Traditionally, scientists speculated that stone-age people raised wolf puppies from infancy and thereby favored genes for tameness, resulting in the development of dogs as we know them. The biologist who appeared on the show, however, thought this scenario didn't make sense, because the critical period for taming a wolf cub would have been so early in the animal's life that adopting and raising one would take too much effort. What incentive would prehistoric cultures have to do this with any frequency? Instead, it's proposed that proto-dogs effectively domesticated themselves. When Mesolithic people began to establish permanent settlements, they produced garbage dumps. Wolves would have scavenged from these stockpiles of food scraps, as wild animals often do today. Here's where the concept of flight distance—the point in a human being's approach when the animal flees—comes in. Wolves with an instinct for a shorter flight distance, letting people get closer before the animals run away, would get better nourishment and leave more descendants. So a subspecies of wolves self-selected to allow closer contact with human beings would evolve. Eventually the gene for tameness would dominate in this population, and the former wolves would become the dogs we know.
You've probably heard about the famous Russian multi-generational fur fox experiment. Within a surprisingly short time, interbreeding foxes that accepted human contact more readily than others produced a group of foxes almost as tame as dogs. Some even learned to respond to their names. Even more intriguingly, the docile foxes showed physical changes in traits such as head shape, coloration, tail position, and heat cycles. The shift to a more "dog-like" appearance is tied to the tameness gene. Many of these characteristics fall under the pattern of neoteny, retaining juvenile traits into adulthood, e.g., the rounder head.Domesticated Silver Foxes
Did the human species domesticate ourselves? Neoteny could account for some of our characteristic human traits such as relative hairlessness (compared to other apes and the vast majority of land mammals) and the retention of curiosity and playfulness throughout life. Elaine Morgan (author of the controversial DESCENT OF WOMAN and other works on the Aquatic Ape Hypothesis) explores in THE DESCENT OF THE CHILD how our species' helpless and prolonged infancy could have driven our evolution into full humanity. Language, for instance. A newborn human baby has virtually no control over most of his or her body. He or she can command the adult attention needed for survival only by crying, smiling, and babbling. Since babbling produces such positive results, no wonder it evolved into language.
It's more pleasant to think we domesticated ourselves than to imagine we're the product of a breeding program by superior aliens. In the pulp-era novel SINISTER BARRIER (1939), by Eric Frank Russell, the Vitons, glowing blue spheres of unimaginably alien intelligence, have shaped human evolution to cultivate us as food. Nourished by psychic energy, they thrive on violent emotions. We are "emotional tubers...grown, stimulated, bred according to the ideas of those who do the surreptitious cultivating." All the bloody conflicts of Earth's history have been "grist for the Viton mill...unwitting feeders of other, unimaginable guts." A far cry from the presumably benevolent experimenters in 2001: A SPACE ODYSSEY who set up monoliths to stimulate ape brains to a higher level of intelligence.
Margaret L. CarterCarter's Crypt
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