What Would Captain Planet Do?

Only the strong survive, long enough to get shot in the face

Posted in Wildlife by Dakota on January 15, 2009

A new study released earlier this week claims that through large scale hunting/gathering humans have become the driving evolutionary force in the animal kingdom.

When humans hunt/fish they generally go after the largest animal. By killing the largest or strongest animal it leaves other less genetically desirable animals to mate in their place, and that puts a kink into natural selection. As a result animals are becoming smaller & reproducing earlier, and when animals reproduce at an earlier age they tend to have less offspring which just exacerbates the problem.

http://uk.reuters.com/article/scienceNews/idUKTRE50B73320090112



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  1. dakota Said,

    As humans hunt, their prey gets smaller: study
    Mon Jan 12, 2009 10:05pm GMT

    WASHINGTON (Reuters) - Hunting and gathering has a profound impact on animals and plants, driving an evolutionary process that makes them become smaller and reproduce earlier, U.S. researchers reported on Monday.

    Their study of hunting, fishing and collecting of 29 different species shows that under human pressure, creatures on average become 20 percent smaller and their reproductive age advances by 25 percent.

    The human tendency to seek large “trophies” appears to drive evolution much faster than hunting by other predators, which pick off the small and the weak, the researchers report in the Proceedings of the National Academy of Sciences.

    “As predators, humans are a dominant evolutionary force,” said Chris Darimont of the University of California, Santa Cruz. “It’s an ideal recipe for rapid trait change.”

    Darimont and colleagues calculated the rates of trait change with a metric called the “Darwin,” after Charles Darwin, who developed the theory of natural selection to help explain evolution.

    They studied changes in the size of fish, limpets, snails, bighorn sheep and caribou, as well as two plants — the Himalayan snow lotus and American ginseng.

    In virtually all cases, human-targeted species got smaller and smaller and started reproducing at younger ages — making populations more vulnerable.

    “Earlier breeders often produce far fewer offspring. If we take so much and reduce their ability to reproduce successfully, we reduce their resilience and ability to recover,” Darimont said.

    The findings fit in with other studies that suggest many fish are over-harvested.

    “The public knows we often harvest far too many fish, but the threat goes above and beyond numbers,” Darimont said in a statement. “We’re changing the very essence of what remains, sometimes within the span of only two decades. We are the planet’s super-predator.”

    Regulations meant to protect the young may in fact be helping drive this unnatural process, Darimont said.

    “Hunters are instructed not to take smaller animals or those with smaller horns. This is counter to patterns of natural predation, and now we’re seeing the consequences of this management,” he said.

    (Reporting by Maggie Fox; Editing by Will Dunham and Eric Walsh)

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