ben moretti on Mon, 18 Jun 2001 03:56:52 +0200 (CEST) |
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[Nettime-bold] cabbage destroyed, soup at 11 |
igor wrote: > So, if we put possible metaphysical discussion about meaning of "creating" > aside, human beings actually created plenty of today's species, subspecies, > varieties, and hybrids. yes! at last some sensible discussion on breeding and genetics. igor referred to botanical genetics earlier in his post, and he is correct, the genomes are much more complex than those of animals. as an example, humans are responsible for breeding the highly diverse varieties of cabbage, brussel sprouts, broccolil, etc all from the wild type brassica oleracea. however as the attached story shows, people can deliberately create new biotypes in a very short amount of time (40 year in this case) science will tell you that human modification of other species genomes, via breeding, has been around for tens of thousands of years. GM is another tool for achieving this ((i am not defending monsanto by saying this)) on a related topic, there is much evidence to suggest that humans have altered climate and environment previously. the case in point is the australian aboriginal use of fire stick farming which was used from 40,000 years ago ~ essentially it converted much of australia's vegetation from temperate/tropical rainforest into sclerophyllous eucalypt based forest with high resistance to fire, plus eradication many species of marsupial megafauna ~ so our curent temperature raising CO2 spewing behaviour is in keeping with our history of being one of many species that alter the environment that surrounds them cheers ben http://exn.ca/Stories/1999/03/30/55.asp A new breed of fox By: Gloria Chang, March 30, 1999 After 40 years of selective breeding, Russian scientists have produced a friendly fox that whines for attention from humans, licks its master's face, and has even begun looking like a dog. "They have shown themselves to be good-tempered creatures, as devoted as dogs but as independent as cats," writes geneticist Lyudmila Trut in the journal American Scientist. Trut heads a research group at the Institute of Cytology and Genetics in Novosibirsk, Russia that's been trying to turn wild foxes into domesticated animals, much like the dog (Canis familiaris) evolved from the wolf (Canis lupus). No, it's not some wacko pet craze, but an effort to understand how wild animals became domesticated. The foxes were selected for tameness. Vicious foxes were excluded from the experimental population. The study started back in 1959 when the founder of the institute, Dmitry Belyaev, chose as his experimental model a species taxonomically close to the dog but never before domesticated – Vulpes vulpes, the Silver fox. Belyaev believed that the changes in domesticated animals were the result of genetic changes from the course of selection. In his view, the factor selected for would not be size or reproduction, as others believed, but for behaviour, specifically tamability. To test his hypothesis, he began a selective breeding experiment that occupied the last 26 years of his life. Now, 14 years after his death, it is still in progress under Trut's direction. Foxes showing slight fear were bred for the next generation. Both Belyaeve and Trut selected foxes for one criterion only – tameness, which was evaluated by the foxes' reactions to their human keepers. If they were vicious, they didn't join the experimental population. If they showed slight fear and friendliness, they did. To ensure that their tameness resulted from genetic selections, the scientists didn't train the foxes and their contact with humans was limited to brief, behavioural tests. Now, 40 years and 45,000 foxes later, Trut has a unique population of 100 foxes that are docile and eager to please. They snarl fiercely at each other for the attention of their human handler. Each of them is a product of between 30 and 35 generations of selection. Offspring of "tame" foxes were calm and showed no negative emotional responses to people. "By intense selective breeding, we have compressed into a few decades an ancient process that originally unfolded over thousands of years," writes Trut. "Before our eyes, 'the Beast' has turned into 'Beauty,' as the aggressive behaviour of our herd's wild progenitors entirely disappeared." But that wasn't the only change. Breeding foxes to strengthen a single behavioural trait also brought about a wide variety of physical changes seen in many animals that become domesticated. Their coat colour, used among wild foxes as camouflage, changed. Irregular splotches of white fur appeared in the domesticated foxes. Their ears became floppy, replacing the straight ones of wild foxes. Their tails began to roll, similar to those in some dog breeds. Their tails also became shorter as did their legs. And although the geneticists didn't select for size, the domesticated foxes were slightly longer on average. Their craniums also changed so that the males became somewhat feminized and both sexes became more dog-like. Reproductive cycles were also affected. The domesticated foxes reach sexual maturity a month earlier than non-domesticated foxes do and give birth to litters that are, on average, one pup larger. Even the brain chemistry among the docile foxes changed. Compared with a control group, their brains contained higher levels of serotonin, a neurotransmitter thought to inhibit animals' aggressive behaviour. A Red fox in the wild. "Evidently, selecting foxes for domestication may have triggered profound changes in the mechanisms that regulate their development," writes Trut in her paper. "If our experiments should continue, and if fox pups could be raised and trained the way dog puppies are now, there is no telling what sort of animal they might one day become." But, despite these lessons learned, Trut worries that their studies will have to come to an end. The continuing economic crisis in Russia has all but dried up the institute's revenue. Their breeding herd numbered 700 in 1996. Last year, that number was cut to 100. There were no funds to feed the foxes or pay the salaries of the staff. To make up for the loss of income, the group has taken to selling some of their foxes to Scandinavian fur breeders. Concludes Trut: "We also plan to market pups as house pets, a commercial venture that should lead to some interesting, if informal, experiments in their own right." The first four fox images are courtesy Lyudmila Trut/American Scientist. -- ben moretti mailto:bmoretti@chariot.net.au http://www.chariot.net.au/~bmoretti news and events in adelaide: http://www.active.org.au/adelaide __o _`\<,_ (*)/ (*) _______________________________________________ Nettime-bold mailing list Nettime-bold@nettime.org http://www.nettime.org/cgi-bin/mailman/listinfo/nettime-bold