From The Labial Groove To The Hiccups: The Oldest Rudimentary Human Traits

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Video: From The Labial Groove To The Hiccups: The Oldest Rudimentary Human Traits

Video: From The Labial Groove To The Hiccups: The Oldest Rudimentary Human Traits
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From The Labial Groove To The Hiccups: The Oldest Rudimentary Human Traits
From The Labial Groove To The Hiccups: The Oldest Rudimentary Human Traits
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Many men suffer from undescended testicles or inguinal hernia, and this is due to a very ancient process, inherited from our ancestor fish, which forms testicles not in the lower abdomen, but in the abdominal cavity

From labial groove to hiccups: Oldest vestigial human traits - evolution, vestigial organs, testes, hiccups, labial groove
From labial groove to hiccups: Oldest vestigial human traits - evolution, vestigial organs, testes, hiccups, labial groove

Our long-standing ancestors were fish and swam in the oceans, this was hundreds of millions of years ago.

But despite the fact that a lot of time has passed since the transformation of fish into land creatures, the human body still retains some residual particles of the "fish" state, which it does not seem to need, but for some reason still exist.

Hiccups

Why do people hiccup? Mankind has been asking this question for certain from the very moment it learned to think. There is no benefit from hiccups, but it causes a lot of irritation, and in the worst case, it can even turn into an obsessive tic that will drive its owner crazy.

A person's hiccups are caused by a spasm of the pectoralis major muscle - the diaphragm, or when air enters the stomach. At the same time, the vocal cords are sharply reduced, which causes a characteristic sound.

Scientists believe that hiccups are mostly the result of how our breathing evolved after splitting with our fish ancestors. In fish, an ancient part of the brain called the brain stem is responsible for breathing. The nerves that activate respiration make a short and simple journey from the brain stem to the throat and gills.

In humans, the brain stem sends signals to the throat, chest, and diaphragm - a much more difficult pathway, and the complex location means that the nerves are sometimes prone to spasm, which causes hiccups.

Labial groove

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Above the upper lip, almost all people have a small indentation that extends to the nose. This is such a familiar part of our face that many do not even notice it at all.

Scientists believe that this rudimentary groove (filtraum) has remained with us since the days of fish-like ancestors. It is formed in the womb at the moment when the general shape of the face is "taking shape", but why a modern person needs it is not clear.

When you are the size of a grain of rice, your eyes are on the sides, and the two parts of the upper lip with the jaw and palate form first as gill structures on the neck.

Over time, the three parts of the face converge and grow together. The groove under the nose remains after these parts are finally brought together, like a healed wound track. If at this stage some kind of malfunction occurs, then the baby is born with a deformity called a cleft lip.

Testicular formation

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In sharks, the testes are located almost in the chest area, next to the liver, and in the human embryo, the testes and ovaries also first form in the same place. But then they have to go down much lower in order to end up where they need to.

For millions and millions of years of evolution, this feature of formation has not disappeared anywhere, over and over again the testicles and ovaries appear in the same place and only later gradually descend.

Because of this, men often have many problems, because their testicles have to travel a longer distance than the female ovaries. Boys may be born with one or both undescended testicles, and they often develop inguinal hernias due to weakening of the abdominal wall.

Why evolution has not yet "fixed" this "bug", scientists do not know.

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