Dust Mites Reverse Evolution, Shock Scientists

Think our evolutionary progress is irreversible? Researchers at the University of Michigan say tiny house dust mites evolved from organisms that specialized and later de-specialized in order to survive over millions of years, Phys.Org reports. The large-scale genetic study, published in Systematic Biology, challenges one of the basic suppositions of evolutionary biology—called Dollo's law—which states that evolution goes one way and cannot be reversed.

But dust mites evolved from parasites that once lived in warm-blooded vertebrates and caused harm to the host. They then evolved into free-living dust mites that lived in nests, and, with the advent of civilization, jumped ship to the sofas, carpets, and mattresses in human homes. What's more, the finding could help us deal with allergies, because house dust mites are the No.1 cause of human allergy symptoms. "Our study an example of how asking a purely academic question may result in broad practical applications," says an author of the study. (More parasites stories.)