Human vestigial organs

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Human vestigial organs
Human vestigial organs
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The vestigial organs of a person are the appendix, wisdom teeth, ear muscles, epicanthus, coccyx, pyramidal muscle of the abdomen and the Moganian ventricles of the larynx.

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Organs that have lost their significance in the course of evolutionary development are called vestigial. They are laid even in the prenatal state and are preserved for life, in contrast to the so-called provisional (temporary) organs, which only embryos have. Rudiments differ from atavisms in that the former are extremely rare (continuous hair in humans, additional pairs of mammary glands, tail development, etc.), while the latter are present in almost all representatives of the species. We will talk about them - the rudimentary human organs.

In general, the question of what is the role of rudiments in the life of this or that organism and what, in fact, is considered as such, still remains rather difficult for physiologists. One thing is clear: vestigial organs help to trace the path of phylogeny. The rudiments show a relationship between modern and extinct organisms. And these organs, among other things, are proof of the action of natural selection, which removes an unnecessary trait. What human organs can be considered rudiments?

Coccyx

This is the lower part of the spine, which consists of three or five accrete vertebrae. It is nothing more than our vestigial tail. Despite its rudimentary nature, the coccyx is a rather important organ (like other rudiments, which, although they have lost most of their functionality, are still very useful for our body).

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The anterior sections of the coccyx are necessary for the attachment of muscles and ligaments that are involved in the functioning of the organs of the genitourinary system and the distal colon bundle). In addition, part of the muscle bundles of the gluteus maximus muscle, which is responsible for hip extension, is attached to the tailbone. We also need the tailbone in order to properly distribute the physical load on the pelvis.

Wisdom teeth

These are the eighth teeth in the dentition, in the common people called the eight. As you know, the "eights" got their name due to the fact that they erupt much later than the rest of the teeth - on average, at the age of 18 to 25 years (in some people they do not erupt at all). Wisdom teeth are considered rudiments: at one time they were necessary for our ancestors, but after the diet of Homo sapiens changed significantly (the consumption of solid and hard foods decreased, people began to eat food that was cooked), and the brain volume increased (as a result of which nature "Had" to reduce the jaws of Homo sapiens) - wisdom teeth resolutely "refuse" to fit into our dentition.

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These "hooligans" among the teeth now and then strive to grow at random, which is why they significantly interfere with other teeth and general oral hygiene: due to the incorrect arrangement of the "eights" between them and adjacent teeth, food gets stuck every now and then. And it is not so easy for a toothbrush to get to the wisdom teeth, so they are often affected by caries, which leads to the removal of a diseased tooth. However, with the correct positioning of the wisdom teeth, for example, they can serve as a support for bridges.

Appendix

On average, the length of the appendage of the cecum in humans is about 10 cm, the width is only 1 cm. Nevertheless, it can cause us a lot of trouble, and in the Middle Ages, "bowel disease" was a death sentence.The appendix helped our ancestors to digest rough food and, of course, played a very important role in the functioning of the whole organism. But even today this organ is not at all so useless. True, it has not performed a serious digestive function for a long time, but it performs protective, secretory and hormonal functions.

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Ear muscles

These are the muscles of the head that surround the auricle. The ear muscles (more precisely, what is left of them) are a classic example of rudimentary organs. This is understandable, because people who can move their ears are quite rare - much less often than people who would not have a coccyx, appendix, etc. rudiments. The functions that the ear muscles performed in our ancestors are quite understandable: of course, they helped to wiggle the ears in order to better hear the approaching predator, rival, relatives or prey.

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Pyramidal muscle of the abdomen

It belongs to the anterior muscle group of the abdominal region, however, in comparison with the rectus muscle, it is very small in size, and in appearance it resembles a small triangle of muscle tissue. The pyramidal muscle of the abdomen is a rudiment. It matters only in marsupials. Many people do not have it at all. For those who are the happy owner of this muscle, it stretches the so-called white line of the abdomen.

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Epicanthus

This rudiment is characteristic only of the Mongoloid race (or, for example, for the African Bushmen - the most ancient people on the planet, the descendants of which, in fact, we all are) and represents the skin fold of the upper eyelid, which we see in the eastern section of the eyes. By the way, it is thanks to this fold that the effect of "narrow" Mongoloid eyes is created.

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The causes of epicanthus are not exactly known. But most researchers are inclined to believe that the skin fold in the upper eyelid arose due to the natural conditions of human habitation - for example, in severe cold conditions or, on the contrary, deserts and hot sun, when the epicanthus is designed to protect the eyes.

Morgania ventricles of the larynx

This organ is a saccular depression located between the true and false vocal folds on the right and left sides of the larynx. They are important for creating a so-called common resonator chamber, that is, a resonant voice. Apparently, the Morgan ventricles were needed by our ancestors in order to create a series of certain sounds and protect the larynx.

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Some others can be attributed to rudimentary organs, in addition, representatives of certain races may have their own rudiments that are not characteristic of other races. For example, steatopygia in the aforementioned Bushmen and related Hottentots, a large amount of fat is deposited on the buttocks. In this case, fat reserves play the same function as humps in camels.

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