Have you ever wondered why you have your hair on your feet but not on your feet?
Or why do we get a lot of hair on our head, but not just our hair on our hands?
The question has been a perennial issue for doctors, researchers and other scientists of the complex mechanism of the human body.
For decades science has been limited to the fact that it is evolutionary character of some animals, but the physiological explanation of how it was produced was a question until recently.
Scientists at the Medical Faculty of the University of Pennsylvania have been researching this "secret" for years and now claim they have come up with an answer.
Study, published in journal journal Cell reports, suggests that the "culprit" No Getting hair in certain areas of our body is a special type of molecule, for a bigger signal, protein.
According to researchers, this is probably the case Dickkopf 2 (DKK2) that blocks the so-called "WNT signaling pathway," the cell channels that are responsible for hair growth.
"In this study, we show that skin in hairless areas naturally creates an inhibitor that prevents WNT from doing its job," he told the journal. Newsweek Sarah E. Millar, one of the investigators.
"We know that WNT signaling is necessary for the development of hair follicles, blockage causes hair formation, and activation causes more hair," he said.
But why do some animals have hair on most of their body and others do not?
Things of evolution
The study suggests that it is, as we have known for many years, evolutionary adaptation.
Research suggests that some animals have evolved to produce DKK2 in certain parts of their body it will help them better survive their environment,
For example, a hairless hand would rather be used to hold tools or other tasks, while the absence of a villi on the feet of the foot would help to walk better.
In cold climates, however, it would be better if they were coated, as in the case of polar bears.
In order to arrive at these conclusions, the team analyzed the skin of the feet of the mouse (which like humans did not have hair on their plants) and compared it with other animals they do like rabbits.
When comparing DKK2 levels between these two species, they found that the amount of protein was significantly lower in the skin of animals that had hair on the foot soles.
Meanwhile, the level of the molecule was much higher in areas where hair grew in the poorest regions.
The study suggests that there are no WNT signal paths in these areas, but hair protein generators are blocking them.
Now scientists hope that this finding can be used to re-research hair growth, treat some illnesses or future treatment in people who have suffered severe burns or accidents.