In the journal Trends in Genetics published an article in two parts (1 and 2), which can kinda Elvish to please the enemies of progress, agitating for a return of humanity to the pristine natural purity. Its author, Gerald Crabtree of Stanford University (USA), argues that in comparison with the ancestors of modern man was pretty stupid. Arguments in favor of this view may formulate any who are in school at least slightly acquainted with the principle of natural selection, but in this study, they look like this.

For the intellectual development of a person is responsible, according to various estimates, from 2 000 to 5 000 genes. Like any other genes, they are prone to mutations. Mutations these can be both good and not so good. Adverse washed out by natural selection. For example, if the individual has appeared mutation that weaken the immune system, he would simply die from the infection, and the chance that after it will remain offspring, very small. And no offspring - no mutations. The same mechanism works and mental abilities.

Once upon a time the person it was vital to show the sharpness of mind. He was inferior to "physical training" wild animals, but because his only hope was the brain. To arrange a shelter or to find food, we had to constantly practice in wit. Bad soobrazayuschie did not survive. Then, however, a time came agricultural crops, the domestication of cattle and other civilizations. And selection that weed out unsuitable, unready, has ceased to operate. From the genetic point of view this means that in those "genes of the mind", which is either two, or five thousand, began to accumulate "mind-numbing" mutations. According to the estimates of Gerald Crabtree, it turns out that every modern person on average two mutations sillier far their predecessors.

It is not quite correct to think about Einsteins, Shakespeares and Jobs: according to a given hypothesis, the Einsteins and the Shakespeares are the remains of the genius of the ancestors, and come forth now man, so to speak, with healthy brain, he would surpass the abilities of all of them collectively. Well-known effect Flynn - the steady rise in IQ modern humans in recent decades - the authors explain the successes of medicine and the General improvement of living standards. That is, we become "better" to eat and to be treated, and this is to some extent balances the negative consequences apoplexy mutations.

However, even people familiar with the concept of natural selection only at school, can present this ingenious hypothesis quite a few valid claims. Her weaknesses are assumed inevitable mind-numbing force notorious mutations and cry for natural selection. First, if we disappeared natural selection, acting on ancient hunters, why in his place not to come to the new selection on other criteria? In the end, according to this theory, the ancient hunters were too specialized to his hunting, so easily switch to a different lifestyle, but quite a transition took place. And secondly, it is not necessary that mutations were necessarily negative. From the same theory of natural selection should that many mutations promote a variety of phenotype, i.e. the emergence of a large number of options signs. Roughly speaking, accumulating mutations could ensure a diversity of skills, ability to use your mind in many different situations and on different occasions.

Well, at last. The variation in the number of genes involved in brain development, says that to establish a clear relationship between genetics and neurobiology at least early. At least until we know exactly how the brain works, how personality and how does the mind of such a global hypotheses would do well to refrain.

Prepared according to LiveScience.