Your Face Mites Are Family Heirlooms

By Nathaniel Scharping | December 17, 2015 11:32 am
demodex

A Demodex mite under 100x magnification. (bill rix/Flickr)

Please don’t want panic, but there’s something crawling on your face. Thousands of them actually, and they’ve been there your entire life.

“They” are part of the species Demodexknown commonly as face mites, and are eight-legged arthropods that live in your hair follicles and snack on dead skin cells. Thankfully, our mites go about their business unnoticed, but not by Michelle Trautwein. She and a group of researchers at Bowdoin College and the California Academy of Sciences have been analyzing the DNA of the Demodex folliculorum mite, because our mites have a long story to tell about human history.

Trautwein’s team discovered that as humanity spread across the planet, our mite friends have been right there with us, carried from generation to generation and place to place, eventually evolving alongside us to the point where distinct lineages of face mites emerged for different ethnicities.

Getting to Know Our Face Mites

Her team collected mite samples from 70 individuals from a range of ethnicities and countries and found that they could break mites into four separate lineages based on subtle differences in their DNA. Distinct strains corresponding to Africa, Asia, Latin America and Europe emerged from their research.

Screen Shot 2015-12-16 at 3.17.51 PM

A graphic showing the distribution of the four lineages of mites across the world. D corresponds to European ancestry. (Credit: Palopoli et al.)

The researchers also traced face mite lineages to a common ancestor roughly 3 million years ago by taking the known rate of arthropod evolution and working backward until a shared forebear was found. This timeframe coincided with the appearance of the Homo genus, meaning these mites and our evolutionary ancestors likely arose at the same time.

Another key finding was that a person’s face mites will remain distinctive to the place they grew up, even after years, or generations, in a different country. In other words, your face mites were passed down to you through your ancestors. Trautwein thinks this is because we inherit our face mites through the type of close physical contact usually shared only by family members.

Trautwein’s research also indicates that different strains of mites may have evolved and adapted to thrive in their host’s unique, facial ecosystem. African mites, for example, would find it more difficult to survive on a person of Latin American descent. This living record makes it more likely that different strains of mites will stay with their hosts, strengthening the idea that a person’s ancestry can be determined by examining the genetic makeup of their mite hitchhikers. The team published its findings Monday in the Proceedings of the National Academy of Sciences.

Our Mite-y History

As they compared mite DNA to human geographic distribution, the researchers found that the African and Asian strains were the most similar in terms of DNA, consistent with the accepted theory that humans originated in Africa and migrated outward. They also found that the European mites were the most widespread, and could be found on people from all over the world. This is likely the result of European expansion over the past few centuries, as face mites hitched a ride on the faces of settlers.

Trautwein hopes to use this information to further map the spread of humanity across the globe. By looking for similarities in the mites’ DNA and comparing them with the geographic distribution of the different lineages, she hopes that they will be able to pinpoint when and where human populations diverged.

Oh, the stories you and your mites could tell.

CATEGORIZED UNDER: Living World, top posts
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  • Karuna Murdaya

    Awesome post. Now what would this mean for interracial babies? Would face mite demographics on Barack Obama be determined by how hospitable his skin is to European or African mites (50:50? 70:30?) or would a new strain of mite eventually emerge dominant (say 100% colonization of his face) that was suited to African-European skin?

    • Barbie

      I was wondering also about interracial children, but I think the article says it, that these mites migrate from closeness. Obama was raised by his white mother and grandparents, so it is likely that he has European mites.

      • surfeagleOrg

        You make me wonder if he has African mites from birth.

  • Bob Juniper

    Its funny. Everyone will believe this as if it were Gods truth. But they couldn’t possibly believe in God. God is just not possible,right? Come on people ,wake the hell up.

    • Small_Businessman

      I don’t see any mention of God in this story. Rather, I see a well-presented scientific study with interesting results.

      • Bob Juniper

        They always get to that eventually in these “science ” discussions. 80% of this stuff is wrong anyway.

        • Small_Businessman

          No, YOU get to that eventually. Don’t blame others for your bias.

        • AncienReggie

          “80% of this stuff is wrong” [citation needed]

    • kbj

      What kind of jibberish are you spewing? Oh, fairy tales over facts!
      Facts are facts Bob, the research proves the four major strains, period.

      • Bob Juniper

        Sorry I interrupted your fantasies .

    • Jim Costich

      Wake up to what? You have a photomicrograph of a god living in the pores of some one’s face? We know we have face mites because we now have evidence that they exist and can even trace their DNA. There is no evidence for gods, or fairies, or ogres living under bridges and certainly not in this story which is about spider mites who clean our faces by eating our dead skin.

  • Jim

    Wait, why mite-y similarity shared by Africans and Asians shows migration out of Africa? What about other ethnic groups? Animals’ mites tell same story?

  • surfeagleOrg

    I guess “Ancestors” is going to have to add a new category for finding our ancestor relations.

  • David Kra

    Latin Americans must have a very interesting variety, considering the pure and mixed ancestry natives, Europeans, and especially in Brazil, Africans, and on the Pacific coast, Asians.
    For children of mixed heritages, are the mites mostly maternal? Is that even more one sided where the children grew up mostly in only one parent’s home environment? (for example, among the portion of African Americans descended from slave mothers and slave owner fathers, where the offsprings’ infancy was mostly experienced in slave quarters.)

    • Jim Costich

      Cooties!!

  • Bob Juniper

    Merry Christmas!

  • http://www.naturalearthcraft.com Heidi M

    If the mites migrate through close familial contact, it would be interesting to look at whether children who are adopted into another mite-y racial group have the mites of their biological parents or the adopted parents. You could even look at the age of adoption to perhaps tease out the time frame of mite migration.

    But, let me just say, a sample of 70 is not very large. Let’s see more data!

  • Jim Costich

    With all our interbreeding and mobility of the past 100 yrs. I bet those catagories of mites will start to meld. I’m descended from Northern Europeans but my adopted son is multiracial. We just bought the Nat. Geo genetic test kit. I want to see how Jewish and Neanderthal I am. We know just rumors about his sperm donor. His mom was 100% Sicilian but we think the other half was Hispanic/Black and probably Native American as well. His face mites could be anyone’s guess!

  • surgeen

    “African and Asian strains were the most similar in terms of DNA, consistent with the accepted theory that humans originated in Africa and migrated outward. ” – does anyone else has a problem with this consistency argument?

    Given that the mites eat dead cells, it would seem that their type would depend on the constitution of the dead cell of the host and the environment the host is in – does one of these strictly depend on the host-ethnicity? And why would it not change when the host goes to another place and has close contact with someone of another ethnicity – wouldn’t the weaker ones die or evolve?

  • Sardu

    When there is an error within the first three words that hasn’t been corrected in four months, is the rest of the article really worth reading? Is the publication really worth reading? What other errors are lurking even deeper within the story that neither the author nor publisher seems to care about?

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