In nature, only a few mammals are monogamous, and birds are also practically monogamous. After the human civilization into the era, although some areas and ethnicity polygamy, but the mainstream or the implementation of monogamy, many countries even with the law to protect the marriage system.
How did this monogamy marriage system initially come into being? Why is civilized society generally pursuing this system? Why some people will abandon this system?
For the prevention of infanticide, forced out of monogamy?
Not long ago, the British researchers to solve the mystery of the origins of monogamy, collected 230 primate gene data, and accordingly to draw out their relationship between the genealogy. Through the study of the prosperity and decline of different tribes, they found that "risk of infanticide" is the most important reason to promote monogamy.
Because the study found that monogamous monsters pursued polygamy compared to the implementation of polygamous groups, their children to adult high probability of their members of the general life span is long, indicating that monogamous groups can better Protect the cubs, so as to avoid the other non-pro-male kill, so its high survival rate.
At the same time, monogamy allows the male to share the responsibility of parenting, thus reducing the burden on the female, it is conducive to accelerate the fertility of the female, so as to grow their own ethnic groups. Another benefit of sharing parental responsibility is that females can spend more energy on childbearing, so that the child's brain has a healthy growth period, which will make the offspring become more intelligent. This may be a reasonable explanation of why humans can evolve more powerful brains.
What is the survival rule created by the weak in order to have future generations?
However, American scientists believe that the risk of preventing infanticide out of monogamy, this argument seems reasonable, but the evidence is not sufficient, and many types of animals, there are such risks, but they did not evolve this Civilized habits or systems.
In order to determine what factors have spawned monogamy, American scientists have established a mathematical model that, by entering different factors, to detect which factors have spawned monogamy, which include males that require exclusive mating Rights, etc., after a large number of data processing analysis, scientists found that these factors are not enough to make a species out of the habit of promiscuity.
Later, the scientists made some adjustments to the model input factors, no longer assume that all the male performance will be consistent. Scientists have tested the following: low-grade males offer food to women in exchange for mating; low-level males will only pick their faithful females, and so on. When scientists enter these factors, the mating habits of the whole family developed towards monogamy. Eventually, monogamy swept the whole group.
According to this, scientists believe that the main reason for the birth of monogamy should be low-grade males in the ethnic group in order to obtain mating rights, and take the initiative to continue care (including gifts of food, etc.) a fixed female, so that they occasionally succeed. When this successful experience spreads out of the community, it becomes a matter of course and changes the way of mating the entire ethnic group.
Why some people are not loyal to the spouse?
Scientists point out that, for whatever reason, the birth of human monogamy, the emergence of such a marriage system to promote the evolution of human beings is contributed.
This system encourages human husband and wife to be loyal to each other, and the nature of loyalty engraved in the gene, people have a "loyalty gene." Even in some countries and regions there is polygamy, this system also provides for women's absolute loyalty to men, and this system is also some primitive primates chaotic mating habits completely different.
Since the "loyalty gene" provides for loyalty between spouses, then why are some people in real life infidelity spouse, can not always adhere to monogamy? Could it be that their genes are out of order?
British researchers found that female twins, if one of them had infidelity spouse, another about 55% chance to have a similar situation. US researchers through the 8000 pairs of male identical twins and fraternal twins comparison, found that the former than the latter is more likely to have the same marital status. This suggests that divorce or infidelity to spouses is likely to be affected by the genes.
Recently, a Swedish team of scientists tested more than 1,800 female DNA and investigated their partner. The results found that women who carry the "infidelity gene" in the body are generally more intimate with others and are more difficult to enter the marriage hall; even if they are married, they maintain a harmonious and stable marriage compared to those who do not carry the gene The possibility of less 50%. And this "infidelity gene" is actually "loyalty gene" variants. As for what causes this gene mutation, is still an unsolved mystery.
This series of phenomena strongly shows that mankind has been through the "loyalty gene" to maintain monogamy, human beings have long been profound understanding from the bones, monogamy is an important cornerstone of human health development.