Eyebrows are hairy ecosystems, home to many microscopic hair mites but as per a DNA analysis, these mites are very loyal, thus helpful for scientists in suggesting ancient human migrations. With the help of it, they could also find fresh treatments for common skin ailments.
A species called demodex folliculorum lives in and around the hair follicles of living beings. Michael Palopoli, Bowdoin College evolutionary geneticist, along with his colleagues sampled the DNA of the mites that live on different group of 70 human hosts.
After sequencing the mitochondrial DNA of mites, scientists found distinct lineages that closely matched the human hosts’ ancestral geography. A mite lineage was common in all European ancestry people, no matter where are they living now. It remained same even after generations in other locations. Other mite lineages were mainly found among people of African, Asian or Latin American ancestry.
Palopoli said that there were some probable reasons for this strange mite fidelity. His colleagues supported the co-called skin traits model. He explained, “There may be something about skin of people from different geographic origins that may be selecting for mites from different mitochondrial lineages. But we don’t know what it might be about skin that may be selecting for one lineage of mites over another.”
With the help of this line of inquiry, researchers may find answers to mysteries of how and why otherwise kind mites were earlier associated with skin disorders like rosacea and blepharitis, or eyelid inflammation.