Atavism in humans - what are they for?

Atavisms are one of the most interesting and mysterious subjects to study in biology, since on the one hand, they allow us to recognize the ways of communication between a modern person and the natural world, and on the other, let us know what our ancestors were and how they lived. This phenomenon is peculiar not only to man, but to all other representatives of the world of wildlife, because we all change with time in order to better adapt to the changing environmental conditions.

What is atavism

Atavism is the fact of appearance in a particular species of organisms of certain features that were characteristic of their ancestors, but lost in the process of evolution. Their appearance is due to the fact that DNA does not lose with time those genes that are responsible for these signs, although in most cases their manifestations are blocked by repressor genes. Thus, if suddenly the action of the repressor disappears or decreases, the atavism in a person and any other being reappears.

Examples of atavisms in humans

The human body is a complex system in which each cell serves to perform certain functions. But on closer examination it turns out that this is not always the case, and examples of atavisms in humans clearly demonstrate this.

Appendix

For sure, every person at least once in my life heard about this vermiform appendix of the intestine. Previously, it was necessary for the accumulation and storage of cellulose and was involved in the process of hematopoiesis, more precisely in the production of leukocytes, but over time, people began to consume more refined foods and the need for an appendix was no longer needed. Currently, he often becomes the reason for an operation to remove it due to developing inflammation. There are cases when he was absent altogether.

Muscles

Far from always atavism in humans is associated with specific organs, in fact it can be any part of the body. Despite the fact that his life has changed a lot, his body still has a large number of muscles, which they are no longer used for their intended purpose. For example, human atavisms include the appearance of the ability to move at least a little with their ears, which their ancestors certainly could have done in order to better capture sounds during the hunt. Also, human atavisms manifest themselves in the presence of subclavian and palmar muscles, as well as plantar muscles, although they can use them to write or lift small objects.

Coccyx

Atavism also includes the presence of coccyx, which was once probably the tail. Sometimes atavisms in humans cause him more inconvenience than good, as in the case of the coccyx, since he does not carry any functional load, but his fracture or damage is very painful.

Shivers

The feeling of goosebumpsia occurs in a person in very different situations under the influence of external and internal stimuli. In fact, the sensation of creepy is exactly what we see, for example, in cats and dogs at the sight of enemies, that is, bristling. A modern man has much less hair on his skin than other mammals and his distant ancestors, so we can not fully bristle.

Nose

Call the nasal cavity a full atavism can not, but sometimes the atavism of a person is partial. The scent of modern man is far from as good as the scent of his ancestor, although up to now some people have a sense of smell more acute than others, which allows them to work in the field of perfumery and become unique specialists.

Sometimes science can not say exactly whether this or that attribute is atavism, but, perhaps, with the course of evolution, nature will reveal to the person all its secrets. At present, we can only imagine and imagine, hoping to receive confirmation of our inventions.