SCRATCH RANDOMNESS:

Humans evolving slower than previously thought, study finds (Jennifer Welsh, 6/16/11, CS Monitor)

The researchers, reporting their findings June 12 in the journal Nature Genetics, based their measurement of evolution speed on the number of new mutations that occur during one generation in each of the families. A slower mutation rate means we probably separated from chimpanzees evolutionarily longer ago than previously thought, the researchers say, adding that the finding may have medical implications, if some groups of people are more mutation-prone than others.

"This makes us think about what are the underlying mechanisms of these mutations, other than just a random process," said study researcher Philip Awadalla, of the University of Montreal in Canada. "Why are there differences in the rate or accumulation of mutations in individuals?"

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