For scientists wondering how bdelloid rotifers escape malicious parasites, the answer is blowing in the wind.
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The tiny freshwater invertebrates, which live in ponds, streams and moss the world over, are notorious among biologists for two unique traits. They can survive for up to nine years as dry, desiccated grains, and they have never been caught having sex. The species has only females, as far as scientists can tell, and one generation creates the next by cloning.
New work appearing in the Jan. 29 Science shows how these traits might be related. Drying up and blowing away helps rotifers avoid parasites. And that may explain how the species can survive without sex, a costly but necessary evolutionary strategy for most organisms.