In recent years, young people's desire to get married and have children has become less and less, which makes many experts very anxious. After all, our country has begun to enter the aging stage. Therefore, while the country is encouraging more children, it is also trying to find the root cause of this problem .
Aging Crisis
If animals knew that humans were worrying about such trivial matters as "reproduction", they might find it ridiculous. Because has a fixed estrus period every year for animals and unique hormonal effects, they must complete the task of mating and reproduction.
So, why do humans not have a fixed "estrus" like other animals, but can do it at any time, and can fight against "hormones" and stick to their own inherent choices?
The estrus period of animals
The biggest difference between humans and animals may be that we have developed civilization. Therefore, in the animal world, there are no restrictions moral codes . When the estrus period comes, animals can choose partners for mating at will, and sometimes they can even have multiple partners.
Male lions with multiple partners
For example, the wild cats downstairs in the community, When they are in estrus, a female cat may mate with multiple male cats and give birth to offspring. Although male cats will not assume the obligation to raise children, the "cuckold" on their head is indeed very conspicuous.
In nature, almost all animals have a fixed estrus period. During this stage, they will be extremely active and seem to be completely controlled by hormones in the body. However, when the estrus period ends, the animals will lose interest in mating and return to their "solitary life."
A solitary Siberian tiger with no intention of falling in love
Many people may wonder why animals must be restricted to a certain range of estrus, why can't they achieve free love all the time?
This is actually that meets their reproduction needs. Because animals live in the wild for a long time and are affected by the four seasons and environmental changes, they need to consider the survival rate when they reproduce.
For example, if is in estrus in autumn and gives birth to in winter, not only will have less food, but the temperature will also be lower due to the cold weather. , the newborn cubs may die soon, and this kind of breeding is ineffective breeding .
Therefore, animals generally choose the estrus period in a suitable season , such as spring .
At this time, everything is recovering. Not only is there no shortage of food, but there is also warm sunshine and just the right temperature. This allows the female animal to find more food on its own after mating and help the offspring in the belly to develop.
Deer mother and child
And in fact, ovulation is still relatively energy-consuming for female animals, so if you do not set an estrus period and maintain ovulation throughout the year, it will also be detrimental to the survival of the female. In short, animals must balance the relationship between survival and reproduction . After all, if they can't even save their lives, let alone reproduce.
Survival is as important as reproduction.
In this case, it is a good thing for them to have a fixed estrus period. Because the entire process of mating, pregnancy, and childbirth is actually facing danger, can mate and reproduce at any time, which is detrimental to the survival of animals.
So why do humans and other animals behave so differently in this regard? What would it be like if the human world also had a fixed "estrus"?
Why don’t humans have estrus?
As we said above, animals have estrus because this mechanism meets their reproductive needs and can help them avoid some dangerous factors.
and The reason why human does not have an estrus is also obvious. Because we have gained many advantages and opportunities during the evolution of and , so we have changed the strategy of reproduction.
Human Evolutionary Strategy
However, this development is actually more tortuous than and .Humans do not have estrus and can do it at any time. The first reason is that there was a need to expand the population at that time. The second reason is that the human reproductive cycle is indeed relatively long in the animal kingdom, and it is difficult to have one child. In this case, if it is still limited by the estrus period, then the number of people cannot increase rapidly in a short period of time.
Of course, the above two reasons can be regarded as shortcomings of human beings in the early stages . After all, before our brains are well developed, compared with various animals, humans have nothing but a "big brain". Strengths.
So I first chose instead of estrus , probably because wanted to make up for the problem of population decline and too few births at a time as soon as possible.
Need to expand the crowd
And in the later stages, human brains are developing better and better, and they have learned to use fire and eat cooked food , which means that we no longer need estrus.
Above, we mentioned that many animals choose their estrus period in spring because everything revives in spring and there is more food. Herbivores at the bottom of the food chain have grass to eat, while carnivores at the top of the food chain can eat herbivores that have fattened themselves. In general, everyone has something to eat.
The discovery and use of fire
Humans are not very limited by food. After all, we are omnivores. Although food is indeed scarcer in winter than in summer, we will not "starve to death".
In addition, humans' omnivorous nature and habit of eating cooked food also make more energy retained in our bodies. At this time, women are no longer like female animals, worried that ovulation will consume themselves and affect their survival.
Many scholars believe that cooked food saves eating time, shortens the process of chewing and digesting food, and allows the human body to absorb richer nutrients; cooked food decomposes the tough meat and fiber of roots into amino acids and sugar, thus reducing the weight of the human body. The burden on the digestive system delays premature aging of human body functions.
The benefits of eating cooked food
It is worth mentioning that we cannot ignore the evolution of human society. When marriage forms and family forms are gradually fixed, people's productivity gradually increases, and there are sufficient living resources . Many times, you no longer have to worry about whether you have a good meal or not, so you can complete the task of reproducing offspring in your free time.
And with the evolution of human beings, they are increasingly unwilling to be completely controlled by hormones. Although hormones still have an impact on us, human ancestors still believe that "your own body should be determined by yourself".
To sum up, not being restricted by a fixed estrus period is a shackle that humans must break free from when they move to the front of the food chain. However, in essence, this problem seems to have never restricted us.
The influence of hormones
At this point, the choices made during human reproduction have been roughly explained. Next, let’s talk about the unique ovulation period of human women.
Human women hide their ovulation period
If you have ever experienced pregnancy preparation, you should be familiar with calculating ovulation period , but the ovulation period is sometimes not completely accurate, which is very confusing. Not having a fixed estrus period is evolution, so why isn’t the monthly ovulation period also fixed? Or rather it was hidden.
Ovulation period
Scientists believe that there may be two reasons why human women make the choice to hide their ovulation period.
The first is the "Male Investment Hypothesis" . This hypothesis believes that when the ovulation period is uncertain, men can be unable to obtain accurate reproductive signals , so that they can stay with the woman to take care of her, making the relationship stable. sex. Of course, the premise of this hypothesis is that "reproduction" is the highest need.
Increase the stability of family relationships
The second one is "reducing infanticide hypothesis" , which believes that in the primitive period of human beings, there would be uneven distribution of "female resources".In that era of law of the jungle, many people would kill the offspring of competitors to prevent them from reproducing. Especially when social relations are relatively chaotic, hiding a woman's ovulation period is equivalent to hiding the biological father of the fetus, which may allow the child to escape.
There was also a struggle among primitive people
Athena Actipis said: "For many years, I was puzzled by the male investment hypothesis, so I began to study how to test it. And the study of female social activities made me feel Shocking, because women may internally bully other women who show ovulation, so hiding ovulation can bring benefits.”
In addition, many scholars have found through research that this situation may also be related to the decline of women’s status and same-sex competition. related. When a tribal leader has multiple wives, the pregnant one may be ostracized by others, so from a certain perspective, women may hide their ovulation periods to be wary of other women.
This is obvious in many palace dramas. Smart people in the early stages of pregnancy generally rarely make any announcements, but wait until the fetus is firmly seated before announcing the news.
There is also competition among women
