25 November 2009

Out-evolving extinction

...where no previous capacity exists, evolving a brand new trait can be a slow and haphazard affair.

If [as experiments with bacteria indicate] most organisms have to wait 31,000 generations to evolve a new trait [that allows them to thrive in radically different circumstances] — they will probably go extinct first. Worse, many natural populations are shrinking fast, further reducing their evolutionary potential. In short, we can expect that — if the environment continues to change as rapidly as it is at the moment — many creatures will fail to meet their evolve-by dates.
This is interesting, but how far can one make an analogy between micro and macro-organisms? It's one thing for bacteria to evolve to consume altogether different nutrients -- say methane rather than sugars. But multi-cellular organisms are, I guess, incapable evolving such a change. Hares and lions will never switch to eating, say, sulphur. Their best chance is if adverse anthropogenic pressures are reduced.

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