Do you have a family of "five generations" around you? I believe that more people have only seen it in news reports, because this requires that the age of the elderly in the family be at least close to 100 years old or over 100 years old. The elderly who can reach this age are really "long-lived".
A big family of five generations
How to prolong their life expectancy and linger in this beautiful human world for a while is a problem that human beings have been exploring since ancient times. Previously, scientists had inadvertently discovered the secret of male sheep's longevity, which may apply to humans, but what needs to be discarded is extremely tangled.
So, what is the secret of sheep longevity? What limits it to "promote use"?
Lovely male sheep
The secret of male sheep longevity
Herders in many countries around the world have mastered a unique skill, which is to "castrate" sheep. Castration is actually castration, because in the absence of reproductive needs, the sheep after castration no longer have a "estrus period", which is easier to manage and the meat quality is better.
Neutered male sheep
Of course, after castration, the life of the sheep will also become longer, so in order to obtain more wool, many male sheep have been deprived of the opportunity to reproduce and become veritable "tool sheep". The scientists who discovered the secret of male sheep longevity came from the University of Otago in New Zealand, and after a collaboration between the university's research team and the University of California, they selected 432 sheep from the local area as experimental objects.
Merino Rams
In order to be able to see the difference by comparison, there were male and female among the sheep, and in particular, some of the rams were castrated. Through long-term comparisons and studies, scientists have come to the conclusion that castrated male sheep live longer than uncastrated sheep. From the changes in the methylation pattern of their DNA points, it can be seen that the castrated male sheep are more similar to the female sheep and tend to change.
Steve Horvath of UCLA believes that after a period of observation of the subjects, it was found that the castrated male sheep had slower changes in aging genes. According to theoretical calculations, the average age of these males is up to 60% longer than that of full rams.
Dna methylation in three groups
It can be seen that after the emergence of this change, their DNA aging rate is significantly reduced, so the life span can be longer. In fact, before the experiment, some herders had found that their castrated male sheep had become extremely viable, and some of them had a much higher lifespan than the average sheep. It's just that before scientific exploration, everyone didn't understand how the male sheep mastered this "longevity secret", and now it is easy to understand from the experimental results.
Speaking of which, I think everyone has already understood why this longevity secret makes people feel extremely entangled. You know, humans are not sheep, castration surgery in addition to the existence of ancient times, in modern times in some countries has been in the form of "punishment", is specifically used to punish rapists. Therefore, even if it is known that this way can live a long life, normal people cannot accept it.
There is a limit to cell division in carbon-based organisms
Of course, the scientists who did the experiment said they expected to find more information about the mechanism of aging and find the "secret of longevity" that applies to humans through the results of the experiment. Maybe in the future, we can seek advantages and avoid harms, and we will improve the methods found in male sheep to make them live a long life without making people entangled.
However, many may argue that the results obtained in animals do not necessarily apply to humans, after all, various characteristics of living things are different. In fact, judging from the life span of ancient eunuchs, it seems that this "secret" is true. But this time we have to look away from the superficial castration and pay attention to the real reasons inside.
Eunuchs in film and television dramas
"Into also testosterone, defeat also testosterone"
Ancient eunuchs were required to undergo castration before entering the palace, which seems very inhumane in modern times, but it is indeed a product of that era. These eunuchs were like castrated rams on the farm, "tool men" in the dynasty, they did not need a complete body, they just needed to obey and do things.
Professor Min Geng kim and colleagues at Incheon Inha University in South Korea studied the life history of 81 eunuchs of the Joseon Dynasty, and through genealogical analysis, the average life expectancy of these people reached 70 years, which was 14-19 years longer than the average male with similar socioeconomic status in the same period, and 3 people were even more than 100 years old.
Korean domestic official in film and television dramas
It can be seen that men who have undergone castration surgery do indeed become long-lived. The root cause of this situation lies in the body of "testosterone". This is a steroid hormone, the main male hormone, which is found not only in the human body, but also in the bodies of reptiles, mammals, birds and other animals. However, testosterone in men is much higher than in women, with levels 7 to 8 times higher than in women.
Testosterone levels decrease with age
In this case, the secretion of testosterone by normal men will make their bodies look stronger, but it will also affect their "longevity". Because testosterone receptors are almost all over the body's nucleated cells, it will have a "long-term impact" on people's physiology and psychology. A doctor named Rodden in the United States found through mouse experiments that testosterone suppresses the function of the male immune system.
The data show that in the experiment, after Rodden removed the testicles of male mice, he found that the number of immune cells in the mice was significantly increased, which meant that the immunity of the mice was significantly enhanced. The presence of testosterone suppresses the male's immune system, making the male's own resistance and repair ability inferior to that of the female.
The difference between the two males' testosterone levels
So, the presence of testosterone, while making men look more robust, has some advantages. But from the perspective of longevity, excessive secretion of testosterone will inhibit the "play" of the immune system, making men more prevalent and aging faster.
It is worth mentioning that the longevity of ancient eunuchs is in stark contrast to the "premature aging" of modern Thai demons. Doesn't it say that castration makes men live longer? Why doesn't it apply to the "shemale"?
Thai Shemale Beauty Contest
This is because although the shemale also chose castration surgery, in order to make themselves look more like "women", they would inject a lot of estrogen. This estrogen, after injection, can indeed make them look "male and female", but it will also cause great harm to the body. Therefore, from the point of view of the injection of synthetic hormones in vitro, there is still an essential difference between eunuchs and demons.
In addition, it should be noted that the shemale injects estrogen because this hormone is synthetic, and real estrogen is the reason for women's longevity. Why?
The longest-lived South African woman in the world
Because testosterone suppresses the function of the immune system, estrogen helps to produce and regulate lymphocytes. Katsukawa, a professor at the University of Tokyo in Japan, said that the estrogen secreted by women before menopause will protect their cardiovascular system and affect the immune system, making the aging rate of their immune system slower than that of men of the same age.
In fact, when we look at the whole natural world, we will find that there seems to be some kind of "law" hidden in it. Many long-lived animals do not mate frequently, and their reproductive cycles appear to be very long.
Schematic diagram of changes in estrogen in women
The relativity of longevity to reproductive capacity
In nature, there is such a creature, the length of life of the male and female is very different, the female life expectancy is about 3 years, and the male after the breeding period, will slowly die, up to 1 year. The creature is called the Tasmanian shrew, and its males mate frequently with multiple females during the breeding season, exhausting their physical strength and energy and eventually dying.
The Tasmanian Family: "Suicidal Mating"
On the other hand, some long-lived animals, such as the cave salamander that lives in the cave, some can do it for 7 years without moving a step. Mating is also mating only once every 12 years or so, in this case, they use "laziness" to make themselves become unusually long-lived.
Organisms at the bottom of the food chain tend to have stronger reproductive ability, and can give birth to many offspring at once, which is completely the possibility of winning the continuation with "quantity". But in this case, their lifespan will also be shorter, not a star and a half compared to the carnivores that belong to the upper class.
Cave salamander
Of course, if this is placed in human society, there are more influencing factors. However, from the demographic comparison of many Western countries and African countries, it can also be seen that good material living conditions will make human life longer, but it will also reduce their desire to produce offspring. So, even if the longevity secret of sheep is improved and then promoted, how many people will choose to accept it?