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Deep-Sea Microorganism Hasn't Evolved For Over 2 Billion Years
sfcrazy writes: Evolution is a natural process — everything evolves over a period of time, depending on the environment. But now scientists have discovered an organism which hasn't evolved for over more than 2 billion years. That's almost the half of the life of the Earth. "The scientists examined sulfur bacteria (abstract), microorganisms that are too small to see with the unaided eye, that are 1.8 billion years old and were preserved in rocks from Western Australia’s coastal waters. Using cutting-edge technology, they found that the bacteria look the same as bacteria of the same region from 2.3 billion years ago — and that both sets of ancient bacteria are indistinguishable from modern sulfur bacteria found in mud off of the coast of Chile." Scientists say the extreme stability of the environment around the organisms made further adaptations unnecessary.
Morphological changes may have been minimal, but I suspect genomic changes have still occurred. Neutral drift alone would assure that these bacteria were not identical at the molecular level to their two billion year old ancestors.
The world's burning. Moped Jesus spotted on I50. Details at 11.
sometimes there is no force nor need for evolution.
.. and from TFS:
...made further adaptations unnecessary.
It really bugs me when I see the theory of evolution referred to this way. There is no "need" or "desire" or "necessary" involved. Similarly, "survival of the fittest" has nothing to do with who is in the (subjectively) best shape or who is the smartest (though there may be correlations). Fish did not decide that they'd like to walk on land or breath air (if they did, it had nothing to do with that happening).
If these things haven't evolved in 2 billion years, it simply means that any mutations that may have occurred resulted in lines that did not reproduce as effectively. That's still a very impressive feat, but it's not because it didn't "need" to, it's because when it did change it didn't do as well. In this case, it's very likely that this is at least partially due to the simplistic nature of this bacteria (fewer dip switches in its DNA, so to speak) and, of course, as the article points out, the very consistent environment (allowing for an optimized implementation to consistently out perform any random brethren).