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Keyword: selectionpressure

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  • 'Super-Predator' Humans Force Evolution in Animals

    01/14/2009 1:56:00 PM PST · by em2vn · 33 replies · 615+ views
    Foxnews ^ | 01-14-09 | Robert Britt
    Acting as super-predators, humans are forcing changes to body size and reproductive abilities in some species 300 percent faster than would occur naturally, a new study finds. Hunting and fishing by individual sportsmen as well as large-scale commercial fishing are also outpacing other human influences, such as pollution, in effects on the animal kingdom.
  • Why did our ancestors start walking upright? Ancient terrain may hold clue

    05/26/2013 8:51:35 PM PDT · by SunkenCiv · 48 replies
    Christian Science Monitor ^ | May 24, 2013 | Eoin O'Carroll
    A study suggests that rocky landscapes in East and South Africa could have pushed our apelike ancestors toward bipedalism. Being four-legged has its perks. As a quadruped, your center of gravity is lower, there's less wind resistance when you're running, and, best of all, you can use your hind foot to scratch your ear. All of this raises a big question: What were our apelike ancestors thinking when they started walking upright? A prevailing hypothesis is that they were prompted by climate change. As African forests declined due to temperature fluctuations some 2.5 million years ago, the hypothesis goes, our...