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Scientists have put forward a new theory about the duration of pregnancy
Last reviewed: 23.04.2024
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The newborn child of man in comparison with the cubs of other primates is born less developed in terms of motor and cognitive abilities.
For a long time, scientists have explained this, relying on the main distinguishing feature of man - the size of the brain. For the large brain, a large head is needed, which hardly passes through the birth canal. Therefore, according to scientists, nature has shortened the duration of human pregnancy, so that the baby would be born before his head becomes too large for normal births. As a result, the child appears almost helpless.
A longer gestation period for the birth of a more advanced baby would be possible if the women had a wide enough pelvis, but scientists assumed that in this case people, like upright animals, would not be able to move normally. However, the professor at the University of Rhode Island, Holly Dunsworth, doubts the validity of this explanation, as in the whole of the above generally accepted theory.
If you take into account the size of the mother's body, then in humans the pregnancy lasts even a little longer and newborn babies are somewhat larger than other primates.
The professor wondered if the metabolic processes in the body in future mothers could be an explanation of the timing of human pregnancy.
By studying this issue, Dunsworth engaged with an expert in physiology, Peter Ellison of Harvard University and Hermann Pontzer of Hunter College.
Scientists have developed a new hypothesis about the timing of the fetus in the womb of the mother.
"According to our theory, children are born when they are born, because at that moment the mother does not have enough energy to ensure the embryonic development of the child. Mom's energy is the main evolutionary limitation, not some hips, "says Dunsworth.
"Our body can burn a limited number of calories daily," explains Pontzer. "During pregnancy, a woman reaches this limit and the baby is born before this limit is exceeded."
This process, due to the metabolism of the mother, explains the reason for the helplessness of babies compared to our relatives, primates.
Another argument of experts in favor of his theory was anthropological research, on the basis of which they concluded that the male pelvis is more suitable for labor than female.
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