Tiny eight-legged creatures have facial sex while they sleep, new research reveals.
Invisible to the naked eye, the mites are found on everyone’s skin — and have bizarre mating habits.
Entwined pairs cling to our hair as they mate – the bug world’s version of ‘swinging from the chandeliers’.
They are passed on at birth and are worn by almost everyone. Numbers peak in adults as pores enlarge.
Now scientists have lifted the lid on the secret life of living beings – from their physical characteristics to their evolutionary future.
The very first complete DNA analysis shows that they are becoming organisms so simplified that they may soon become one – with us.
Co-lead author Professor Alejandra Perotti, from the University of Reading, said: “We found that these mites have a different arrangement of body part genes than other similar species as they adapt to sheltered life in pores.
“These changes to their DNA have resulted in some unusual body traits and behaviors.”
There are more than 48,000 species of mites – two of which live on our faces. They can only be seen under the microscope – and they look like dowels.
A long cone-shaped body is supported at one end by stubby legs. We spend more time with the strange creatures than any other animal.
They even protect against acne and scarring by keeping pores unclogged.
Mites are cousins of spiders – and can be found buried upside down in our hair follicles, where they eat the oils we secrete. They hook together near the surface.
Their existence is isolated, without exposure to external threats, competition for hosts, or encounters with other mites.
Genetic reduction has enabled them to survive with the minimal repertoire of proteins – the lowest numbers ever observed in mites.
Tiny legs are powered by just three single-celled muscles. The mites lack UV protection and have lost the gene that makes animals wake up to daylight.
They are also unable to produce melatonin – a compound that keeps small invertebrates active at night.
But they are able to fuel their nightly mating sessions with melatonin, which is secreted by human skin at dusk.
Their unique gene arrangement also leads to their odd mating habits. Reproductive organs have moved forward.
Men have a penis that sticks up from the front of their body. They must position themselves below the female when mating – and copulate while they both cling to human hair.
One of their genes is inverted, giving them a peculiar arrangement of mouth appendages that protrude extra for gathering food. This helps them survive at a young age.
The mites have many more cells when they are young than when they are adults – contrary to the previous assumption that parasitic animals reduce their cell count early in development.
It’s the first step for the mites to become symbionts – very closely bonded to their much larger human host.
Lack of contact with potential mates who might add new genes to their offspring may have set mites down an evolutionary dead end — and possibly die out.
The phenomenon has already been observed in bacteria that live in cells – but never in an animal.
Some scientists had hypothesized that the mites don’t have an anus and therefore must accumulate all of their feces over their lifetime before releasing it when they die – leading to skin inflammation.
But the study confirmed that they do have an anus — and have therefore been wrongly blamed for many skin conditions.
Co-lead author Dr. Henk Braig from Bangor University added: “Mites have been blamed for a lot of things.
“The long association with humans may suggest that they may also play a simple but important useful role, such as keeping the pores on our face unclogged.”
The study was published in the journal Molecular Biology and Evolution.
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https://metro.co.uk/2022/06/22/tiny-eight-legged-creatures-have-sex-on-your-face-while-you-sleep-16866045/ Tiny eight-legged creatures "have face sex" while sleeping