Human beings have never been alone. From birth, the pores on our faces have been accompanied by some kind of creature, and its name is Demodex folliculorum . Recently, British scientists used DNA sequencing to thoroughly study these species that call the human face their home. They found that because they are too dependent on humans, they face threats to their survival due to continuous inbreeding.
My face is a small mite A warm home
Every night, people brush their teeth, wash their face, apply lotion and then go to bed. But at this time, the little mites living on our faces are just beginning their activities.
These little mites that make their home on the face are officially called Demodex folliculorum. Only 0.3 mm in length, it lives near the hair follicles and sebaceous glands of the facial skin. The most common areas are the nose and eyelashes.
First off, yes, there are tiny mites on your face (90% chance, anyway).
These little critters, known as Demodex folliculorum, feast on the oil that oozes from your hair follicles. (Aren't they cute)"
over Demodex folliculorum is found on 90% of people’s faces, but their only transmission route is from mother to child (Source: Pixabay)
Because I love you, change genes
Perotti said: “We analyzed the relationship between Demodex folliculorum and mites. The gene arrangement of other similar organisms is very different. This may be because they are too adapted to the hidden life of human pores, so they change their DNA, which also leads to their special body structures and behaviors. "
Researchers found that the arthropod gene responsible for regulating when to wake up and when to sleep is no longer visible in the DNA of Demodex folliculorum, which also makes Demodex folliculorum extremely dependent on human schedules. Perotti explained: “After nightfall, when we are asleep, Demodex folliculorum mites will visit the pores and then make love and give birth inside. "
Humans automatically secrete melatonin at night. When the Demodex follicles living on the skin notice an increase in melatonin, they will wake up and move around. On the contrary, during the day, when human melatonin decreases, the hair follicles will erode. At this time, the Demodex mites return to the pores to sleep.
In addition, Demodex folliculorum is only active at night. Studies have also analyzed that they no longer have genes that are immune to ultraviolet damage.
A road to extinction
Although it began about 200 million years ago. Since ancient times, mites have established close relationships with humans and mammals, but Demodex folliculorum has become too dependent on humans, forming a mechanism that can only be passed from human mothers to children. In other words, Demodex folliculorum will not leave the human face to find its way around. For new mating partners, even if humans frequently exchange towels to wipe their faces, their own Demodex folliculorum mites will not come to the other person's face.
Such inbreeding also causes the genetic diversity of Demodex folliculorum to be slowly lost. After being passed down from generation to generation, The genetic diversity of Demodex folliculorum is getting smaller and smaller. When the gene pool no longer changes, it will eventually face extinction
Friendship across species
In this study, the researchers also eliminated past erroneous inferences and hoped to replace Demodex folliculorum. Demodex folliculorum has regained its reputation.
Demodex folliculorum has a lifespan of about 2 to 3 weeks. In the past, it was speculated that Demodex folliculorum has no anus and will store all its feces in the body, causing inflammation or acne problems in human skin. After analysis, the researchers found that this is not the case: they have an anus.
Henk Braig, a co-author of this study and a researcher at the School of Natural Sciences at Bangor University in the UK, clarified: "Demodex folliculorum has been known for a long time. All wrongly blamed. It is known from research that their long-term relationship with humans has allowed them to develop parts that are beneficial to humans. For example, it will prevent our pores from being clogged. "
Two British researchers hope that after this study, people will re-evaluate the use of these organisms in human life. Demodex folliculorum is good for skin health. In fact, they coexist peacefully with humans and are good symbiotic partners.
But humans Can Demodex folliculorum be prevented from going extinct? “I don’t think we can stop nature, and we shouldn’t,” Perotti said. But maintaining healthy skin is enough for them to thrive."
(First image source: ""User:Alan R Walker (talk) 09:16, 28 January 2014 (UTC)"", CC BY-SA 3.0, via Wikimedia Commons)
