No surprise: Human predation exerts selection pressures on other species

In a purely humanless world, other organisms would face “purely” environmental obstacles to their own sustenance and hence a different set of pressures than those of today, which include deforestation, pollution, and other ecologically definitive actions perpetrated by H. sapiens sapiens. The result is that adaptations in plants and animals that in the real world are in close contact with humans would generally coour more slowly, or along different paths. (I’m perhaps oversimplifying here, and real biologists are free to take me top task.)
At the other extreme, the directed breeding of animals whose reproductive habits are strictly controlled by humans has led to some extremely rapid evolution. The example that usually comes to mind is dogs, domesticated from wolves only ten or twelve thousands years ago. The variety of dog breeds in existence today–all of which are theoretically capable of mating with both wolves and each other–is staggering, and in unclouded minds serves as unimpeachable testament to the existence of raw, randomly generated DNA substrate upon which selection–in this case artificial selection–can act.
Today, a Yahoo! News article described a situation that lies somewhere in between: Human hunting and fishing activities, while not aimed consciously at breeding in or breeding out animals with new and improved traits, have the same basic effects as antibiotics do on bacteria. Just as an incomplete course of a cephalosporin can result in “superbugs” and pests like MRSA, harvesting of more susceptible fish and game leads, as expected, to the emergence of especially hardy varieties. And this apparently happens three times faster than it would if human activities were not a factor.
The abstract of the study mentioned in the article is here.

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  1. #1 by ColinB on January 13, 2009 - 5:11 pm

    That kind of reminds me of a study that came out a few years back that showed that taking only the larger fish in the atlantic produced populations where fish become sexually mature at a much smaller size – although I can’t remember whether there was a corresponding reduction in age.
    Reduction in fishing pressure produces a much lower pressure selection effect, and hadn’t really helped in restoring the population of fat, trusting fish. Go figure… :-)

  2. #2 by Jim Thomrson on January 15, 2009 - 3:37 pm

    In the name of fair and balanced coverage, take a look at this link:
    http://www.refugewhitetails.com/

  3. #3 by MattK on January 15, 2009 - 7:00 pm

    In the name of fair and balanced coverage, take a look at this link:
    http://www.refugewhitetails.com/

    How is this different from shooting a cow? I hope that these people aren’t releasing this livestock into wild populations to screw around with the gene pool. If you want a big deer with big antlers (why? what’s the point?) get an elk or a moose. This is just as bad as put and take fisheries. I thought the point of hunting and fishing was experience wildlife (the wildlife would probably have another term for it) and to interact a little with nature. Size obsessed gun luvers meet pick-your-own strawberry farms. Weirdos.

  4. #4 by MattK on January 15, 2009 - 7:00 pm

    In the name of fair and balanced coverage, take a look at this link:
    http://www.refugewhitetails.com/

    How is this different from shooting a cow? I hope that these people aren’t releasing this livestock into wild populations to screw around with the gene pool. If you want a big deer with big antlers (why? what’s the point?) get an elk or a moose. This is just as bad as put and take fisheries. I thought the point of hunting and fishing was experience wildlife (the wildlife would probably have another term for it) and to interact a little with nature. Size obsessed gun luvers meet pick-your-own strawberry farms. Weirdos.

  5. #5 by MattK on January 15, 2009 - 7:00 pm

    In the name of fair and balanced coverage, take a look at this link:
    http://www.refugewhitetails.com/

    How is this different from shooting a cow? I hope that these people aren’t releasing this livestock into wild populations to screw around with the gene pool. If you want a big deer with big antlers (why? what’s the point?) get an elk or a moose. This is just as bad as put and take fisheries. I thought the point of hunting and fishing was experience wildlife (the wildlife would probably have another term for it) and to interact a little with nature. Size obsessed gun luvers meet pick-your-own strawberry farms. Weirdos.

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