The analysis of lice DNA helps to learn more about the evolution
There are a lot of versions to explain the evolution of the human being. Marxism classics believed, people left the animal world with the help of labor. Other scientists think, the human evolution was pushed with meat food, the development of language, the weakness of human babies, and so on and so forth. The latest research conducted by German anthropologists made a sensation in the scientific world: the human being became human because of lice. That is why, people's negative attitude to this insect is simply outrageous.
Apes are generally believed to be our closest relatives, although this fact still provokes never-ending discussions. Unlike all apes, a human body is not covered with fur. If an ape and a human being were exhibited in a zoological museum, the visitors would pay all attention to human nudity. This is the reason why a lot of anthropologists call a human being a naked ape. Why did a hunter-ape lose its fur and when did it start wearing clothes? Modern science does not know the answer to this question, although there are a lot of astounding versions to explain it. A human embryo of six and eight months old is covered with thin fur, which reminds the bird fluff. Sometimes, prematurely born infants have fur all over their bodies.
At times, it is good to forget all previous theories and look at a problem from a different angle. Mark Stoneking, of the Max Planck Institute for Evolutionary Anthropology in Leipzig set forth an astounding theory. The scientist paid attention to small insects called human body lice and the role that they played in the evolution of a homo sapiens, when primeval humans started wearing clothes. Clothes mean a lot more to body lice than to fashionable women, because insects lay eggs in clothes. The genetic analysis of the insect showed, lice are 70,000 years old, they appeared soon after human beings started resettling from Africa to Europe, where they had to wear clothes because of the cold.
The absence of fur on human body can be explained with other factors of human evolution too. Nevertheless, when apes stopped migrating and started leading a settled lifestyle, parasites swarmed their "homes." Insects - ticks, flees, bugs - always live in the fur of all apes, whereas humans are lucky not to suffer from it. One can easily see it in a zoo: chimpanzees, one of the smartest apes, spend a lot of their time trying to find insects in their fur.
Thick fur became a source of infection for hunter-apes that started eating meat. Carrion-eating bids do not have feathers on the neck, which is not incidental. Thick fur became even more dangerous, when people started using fire in their everyday lives. New lifestyle, the need to hunt, to maintain warm temperature in caves developed sweat-glands, which made fur gradually disappear.
According to other versions, the fur disappeared because of the need to hunt in water and because of various social trends. This way or other, only lice managed to witness human evolution changes. Dr Stoneking's team is going to study the "molecular clock" in the DNA of human body lice (insects die in another environment in 24 hours). The research will allow to find the mutation speed and human evolution stages.
There are three kinds of human lice - head, body and pubic lice. Doctors try to exterminate them, while scientists evince great interest in those insects. Dr. Stoneking thinks, pubic lice are especially interesting, because the analysis of their DNA will be the best to find out, when our ancestors lost their fur and became humans.