Horses can walk soon after birth, kittens a few weeks old can be left alone while their mother searches for food, while babies can live for many years. need for care is in a state.

The fact that birth occurs after nine months and that the human brain of newborns is relatively less developed compared to other primate species has caused some problems so far. to evolutionary processes was based. However, one study found results suggesting the opposite. Do you think the years-old hypothesis will be refuted overnight?

Our evolutionary process from four legs to two legs

The skeletons of our ancestors evolved over millions of years from a creature that walked on four legs and had a smaller head. Getting into an upright bipedal position, Supports a wide head also means. In fact, this is one of the disadvantages of walking on two legs. Other negative effects may include back and neck pain as the viewing angle increases.

Women suffered the greatest disadvantage because the skeleton supported a large head. Straight posture, more narrow hips It meant. This was a major physical feature that narrowed the birth canal. Women who gave birth prematurely, when their skulls and brains were smaller, survived. On the one hand, this is actually true natural selection made. People whose vital systems were not yet fully developed were born prematurely.

If there were no evolution and humans were born neurologically like chimpanzees, pregnancy would last at least twice as long. This is the pregnancy process 18 to 21 months It would be an extractive process.

Babies’ brains are developed enough to enter the birth canal.

The larger size of women’s pelvis could prevent them from walking. According to the prevailing view, babies’ brains only grow large enough to fit into the birth canal. That’s why it’s not 18 months birth in 9 months occurs.

When babies are born, their brains are less than 30% that of adults. This way they can pass through the narrow channel. This situation, which is one of the reasons why care is needed, begins to return to normal after leaving the womb. Brain development continues after birth and beyond At the end of a year this will double on average.

An investigation could challenge this process that has taken place to this day.

Holly M. Dunsworth of the University of Rhode Island and her colleagues tested the “obstetric dilemma” hypothesis and brought a very different perspective to the event. According to the hypothesis, the female pelvis, which is wider than that of the male, makes it difficult to perform activities such as walking and running. more energy than men that it requires. In their research article, they stated that a wider pelvis did not cause such a situation.

Dunsworth also noted that for the human brain to reach chimpanzee levels (40% of the adult size of the human brain), the size of the pelvis only increases. Extension up to 3 cm He also said it was necessary. This is actually considered within the normal pelvic range of today’s woman. As mentioned, it also refutes the hypothesis that women should expend more energy.

Babies are born when their mothers reach their metabolic capacity.

Dunsworth and his colleagues also answered why babies are born after nine months from a different angle. Dunsworth, metabolic capacity of women He said there is a capacity and when that capacity is full, babies are born.

To continue their normal processes in the first six months of pregnancy, women must twice as much energy They use energy, and this energy increases as the baby grows. The fact that the maximum metabolic rate is between 2 and 2.5 times means that women are not yet able to convert energy after nine months.

Although this study, which claims the opposite of the obstetric dilemma that has existed for years, cannot eliminate the entire hypothesis, researchers still think that these arguments will be valid over time.