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Barry OConnor & Pavel Klimov make the New York Times


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New York Times columnist Douglas Quenqua presents Pavel Klimov and Barry OConnor's research showing that dust mites are evolved from parasitic ancestors.

by Douglas Quenqua:
Dollo’s law... states that evolution always moves forward. But new research on humble dust mites, the tiny arachnids that live in cushions and carpets everywhere, is challenging the law.

Using DNA data to construct an elaborate family tree, two University of Michigan biologists have shown that dust mites — which are not parasites but free-living organisms — evolved from parasites that in turn evolved from other free-living organisms. That would seem to contradict Dollo’s law, since the mites should be unable to readopt the free-living characteristics discarded by their ancestors. "The results show pretty conclusively that dust mites are derived from parasitic ancestors," said Barry O’Connor, an evolutionary biologist and one of the authors of the study, in the journal Systematic Biology.