No need a lot of sperm to produce offspring. But why would a healthy adult male can release 40 million to 1.2 billion sperm cells in the ejaculate?.
Conversely, women are born with an average of 2 million follicles which is the reproductive structure to create an egg.
While only takes one sperm and one egg to meet and make babies, then why the men produced a large amount of sperm?
Is not so it is not extravagant for a man to issue a single sperm, or at least much less to meet with one egg?
The reason for this problem comes down to two words: sperm competition. From earliest times, men have been competing with each other to bring as much as possible their sperm with an egg that may be fertile.
Such competition is an evolutionary imperative for males of each species. If the rival sperm to fertilize an egg, then the opportunity to continue your genes will be lost.
But if this is only a matter of "more is better," then all animal species will evolve ridiculous. Due to large testes will win the competition.
But is not that simple, although the number is also important, as well as distance. Search the egg is not just about how much to produce sperm. It is also about how close.
In the early 1980s, researchers in the United Kingdom and the United States realized that both proximity and number are important factors in the physiology of primates, including humans.
In primate society with rigid social structures and one dominant male is paired with all the women, testicles tend to be small. In gorillas, for example, they are relatively very small compared to his weight.
In a herd of gorillas, one male defending his harem females to ensure that only sperm which will be near their eggs. In this case, make a lot of sperm does not really help male gorillas reach its destination.
For chimpanzees, by contrast, sperm competition is a serious problem. In chimpanzee society, many males and females live together in large troops, and females having sex with many males in a short time.
This is why male chimpanzees have the largest testicles of all great apes, weighing about 15 times larger than gorillas, relative to their weight. It gave him a better chance in the competition.
Humans are somewhere in between gorillas and chimpanzees. Testicle men average about two and a half times the gorilla, but six times smaller than a chimpanzee, relative to body weight.
This led some researchers to question whether sperm competition has succeeded in the human herd, or whether our relatively large testes only to hold the record for the period of our evolutionary history.
Conversely, women are born with an average of 2 million follicles which is the reproductive structure to create an egg.
While only takes one sperm and one egg to meet and make babies, then why the men produced a large amount of sperm?
Is not so it is not extravagant for a man to issue a single sperm, or at least much less to meet with one egg?
The reason for this problem comes down to two words: sperm competition. From earliest times, men have been competing with each other to bring as much as possible their sperm with an egg that may be fertile.
Such competition is an evolutionary imperative for males of each species. If the rival sperm to fertilize an egg, then the opportunity to continue your genes will be lost.
But if this is only a matter of "more is better," then all animal species will evolve ridiculous. Due to large testes will win the competition.
But is not that simple, although the number is also important, as well as distance. Search the egg is not just about how much to produce sperm. It is also about how close.
In the early 1980s, researchers in the United Kingdom and the United States realized that both proximity and number are important factors in the physiology of primates, including humans.
In primate society with rigid social structures and one dominant male is paired with all the women, testicles tend to be small. In gorillas, for example, they are relatively very small compared to his weight.
In a herd of gorillas, one male defending his harem females to ensure that only sperm which will be near their eggs. In this case, make a lot of sperm does not really help male gorillas reach its destination.
For chimpanzees, by contrast, sperm competition is a serious problem. In chimpanzee society, many males and females live together in large troops, and females having sex with many males in a short time.
This is why male chimpanzees have the largest testicles of all great apes, weighing about 15 times larger than gorillas, relative to their weight. It gave him a better chance in the competition.
Humans are somewhere in between gorillas and chimpanzees. Testicle men average about two and a half times the gorilla, but six times smaller than a chimpanzee, relative to body weight.
This led some researchers to question whether sperm competition has succeeded in the human herd, or whether our relatively large testes only to hold the record for the period of our evolutionary history.
(Various sources)
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