Some people may cringe at the thought of harboring tiny living creatures on their face but whether they like it or not, mites that are invisible to the naked eye thrive on people's face. A new study has in fact found that this eight-legged creature is present in 100 percent of the adults that the researchers have tested.
In a new study published in the journal PLOS ONE on Aug. 27, Megan Thoemmes, from the Department of Biological Sciences and W. M. Keck Center for Behavioral Biology at the North Carolina State University, and colleagues revealed of microscopic mites that live on human face.
The creatures, known as Demodex, are relatives of spiders and ticks that thrive on the skin of mammals and live on people's hair follicles eating the oil produced by the skin.
For the study, Thoemmes developed a test for Demodex DNA and conducted face sampling events. In a DNA test involving 19 participants who were at least 18 years old, the researchers found that 100 percent of them carried DNA from the Demodex mites.
The researchers also found that young people were less likely to have the mites, which indicates a possible association between the mites and adult humans, and that two species of this microscopic arachnid that are not closely related, the Demodex brevis and Demodex folliculorum, can be found living in human faces.
"Within our samples, 100 percent of people over 18 years of age appear to host at least one Demodex species, suggesting that Demodex mites may be universal associates of adult humans," Thoemmes and colleagues wrote.
It isn't clear how these tiny mites have spread among humans but one theory proposes that the creatures are passed from mother to child during breast feeding. Study researcher Michelle Trautwein, from the California Academy of Sciences, said that the mites have likely been living with humans for a very long time and may possibly give clues on the evolutionary history of humans.
"We want to know if Demodex DNA can provide a reflection of our own evolutionary history by allowing us to retrace those ancient paths of human migration," Trautwein said. "So far, our analyses look promising. When looking at the DNA from one of our mite species, D. brevis, we found that mites from China are genetically distinct from mites from the Americas."
Although having mites living on one's face may sound icky, the researchers assured that "humans and Demodex are old, old friends."