Monday, October 16, 2006
From George Mason University's History News Network: "Global warming," which may regionally include cooling, drying, humidification, or changes in the seasonality of winds and precipitation, is only one dynamic factor among many contributing to the constant flux of the biosphere. Another factor that will inevitably interact with any climate trend is the continuing redistribution of biota.
Organisms besides humans are affected by climate change, regardless of its causes. If average temperatures rise in the Arctic Ocean and the pack ice shrinks, polar bears and some seals lose habitat. If pack ice becomes rare enough, these animals will be at an ecological, and therefore evolutionary, disadvantage. They might even "blink out" altogether."
... As exemplified by the polar bears, climate change puts the existing biota of any set "place" on the map at mounting risk of being selected against. As prevailing conditions change, adaptations that once promoted survival become irrelevant or even disadvantageous. As far as polar bears are concerned, once the ice melts, "there is no 'there,' there." When abiotic factors shift, biotic ones must shift as well. When it happens too quickly for evolutionary adjustments to occur within populations, other populations - outside populations - better equipped to meet the new challenges may take advantage of the opportunity.
[Ecology, Extinction, Environment, Evolution, Science, Biology]
See "The End of Eden: Gaia and James Lovelock*" at the Washington Post.
(*James Lovelock's latest book, "The Revenge of Gaia: Earth's Climate Crisis and the Fate of Humanity" is currently appearing on the 'Featured Books' page of the Evolution Book Store: UK | US - or go directly to the Amazon book webpage: UK | US).
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