Those pesky little dust mites might upset a long-accepted rule in genetics according to researchers at the University of Michigan. And it turns out that this might be a good thing if you suffer from allergies.
Researchers determined that dust mites actually reversed their evolutionary path. Beginning millions of years ago as specialized parasites, they lived inside warm-blooded invertebrates but caused harm to their host. Then they evolved into free-living mites who lived their lives in nests. Later, when people began making sofas, mattresses and pillows, carpets, and other soft, ready-made hiding places, the dust mites devolved once again to take advantage of the new environment.
One of the foundations of the study of evolutionary biology is the idea that evolution only proceeds forward and cannot be reversed. This supposition, called Dollo’s law, has now been challenged by the dust mites. Now that one example of devolution has been discovered, how many more can we expect to find?