We and our sex

2012/12/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria

• Anatomia/Fisiologia
• Biologia
• Genetika
• Eboluzioa

According to UPV psychologist Eduardo Fano, "our species and its direct ancestor have been adapting to an environment that is not the current one for hundreds of thousands of years. Many of the issues affecting our behavior are treated as if it had not been affected by all this adaptation. That is, we have forgotten who we are and we have not wanted to see some tangible phenomena."

An example of this is “everything that, as in many other species, can mean a differentiated parental investment derived from anisogamy”.

The following is explained: "In our species, one of the sexes, females, produces few and great gametes, and the other, males, small and numerous. Therefore, reproduction for females is very expensive and for us [for males] it is much cheaper. In addition, the investment of the female during pregnancy and lactation is much higher than that of the female. This has given rise, among other things, to intrasexual competition and sexual dimorphism, that is, to the fact that males and females have many differences from the apparent point of view and in other areas."

However, Fano believes that we are a small exception in one thing: "The male's investment in the care of offspring in our species is greater than in other species of primates in our group. In fact, in our species, investing in care can increase reproductive success." He adds that this investment can be of two types, “material and face-to-face, that is, it can put material resources or give surveillance time”.

Reasons for Othello

Eduardo Fano, psychologist at UPV. Ed. Related information

Fano warns that this investment of the male also involves the custody of the female: "In fact, when the investment made by the male for its offspring to live and grow with a partner is large, the female loses much when breeding with other males, as it may be investing in the growth of the breeding that contains genes belonging to another male."

This does not occur in other animal species. In the species in which males invest very little, females suffer less direct surveillance, since they do not lose large investments. Another strategy is to cover the largest number of females.

On the other hand, women do not have the same problems and interests as men, as Fano explained: "If the woman has gotten good genes out of the couple and has a good pattern inside the couple, she has no problem. However, to some extent, throughout our evolutionary history, it may interest the female of our species the tranquility of being tied to a male, as the male as a couple could keep the rest of the group apart."

Fano has also brought other research to the issue. According to them, women are much more vulnerable to physical infidelity than men. But emotional infidelity does less harm to men than to women than to women. "And that looks like a universal. A fairly macho universal, but the truth is that evolution has not taken these things into account."

Thus, Fano considers that in our species, both females and males, have biological and evolutionary reasons to form stable couples. "And there are hypotheses to explain why the males of our species should invest more than those of other nearby species," said Fano. "For example, one hypothesis is that the reason is the slow development of children. It takes a long time to develop and at that time, it also requires a large investment. Foley and Lee calculated in 1991 that a child of our species needs 9% more resources than a chimpanzee puppy in the first 18 months. That's a lot! ".

Fano has stated that studies conducted in different groups and cultures support this hypothesis. In addition, researchers have found that men who invest a lot of material resources in the reproductive unit do not spend much time with their son or daughter, and vice versa, that those who cannot put material goods spend more time at their side. "On the higher level of society, the richest, it is very well seen that man has many goods and is not asked to be with his children. On the contrary, on the lower level the man who has the attitude of caring and being with his children is much more valued."

Although polygamy is accepted in most cultures, monogamy is more frequent. Ed. Jim Boud

Between polygamy and monogamy

Fano considers it important to clarify the question of monogamy and polygamy: "A large majority of cultures are polygamous. However, if we analyze what really happens, among those who are polygamous, polygamy is only exercised in families with sufficient resources. That is, most Muslims do not have four wives; if they are poor, they have only one woman and at most two."

Therefore, the most common thing is monogamy, although polygamy is accepted. "The growth and education of a child of our species is so expensive especially in the early stages of his life, that the tendency to care has a real impact on the success of children." In addition, Fano stressed that this system of victimization structures the entire society.

Other behaviors have also analyzed its universal character. "According to the work done by Buss and Dunbar, in most cultures women choose men who are 4 years older than them. Why? asks Fano. And then answer: "The older men are, the easier it is to achieve social status. And women also choose men with high status, not just good genes."

Without sex, what

Fano confesses that it is difficult to imagine how the world can be if the two sexes were monomorphic and the children did not demand the custody of their two parents: "I think the world would become a totally monochrome world. A lot of features that we have would disappear, for example, fashion, as it would not be necessary to physically attract through parthenogenesis or if it were reproduced. But if we had to reproduce in pairs, sexual dimorphism would emerge again as soon as there are differences in investment."

On the other hand, Fano believes that if each member of the couple invests equally in child care, the characteristics of good genes would prevail. However, he has great doubts about what the good genes would be: "Those who make us strong? Or those who make us intelligent? What kind of intelligence? Would it overcome emotional intelligence? A balance between types of intelligence? I can't imagine what our species would look like without sex. I can't imagine any other mammal, tell me! ".

The specificity of homosexuality

In recent years, in our society, homosexuality has been legally recognized. "But this has happened now and here, until recently and in many places, even today, because homosexuality is excluded."

For Fano, however, many people do not know that in the human species homosexual behavior appears much less than in other primates. "In fact, in primates and among many mammals, homosexual behavior is a common practice." Thus, according to the primatologist Federico Guillén Salazar, it is noteworthy the heterogeneity of the people of our environment [that is, now and in our culture] against other primates.

According to experts, our heterosexual attitude towards other primates is remarkable. Ed. Steve Smith

In any case, from an evolutionary point of view, the function of homosexual behavior is not evident. Fano explained that it is possible that selection does not specifically favor homosexuality, but has advanced along with other characteristics driven by selection. "But there are other hypotheses, such as the existence of a homosexual in the family, which can lead to his brothers being more successful, because he would help them care. However, it is not proven."

From research with hypotheses, primates and human groups from different cultures, Guillén Salazar has concluded that homosexuality and other non-reproductive sexual behaviors are the product of a long evolutionary history. Another conclusion is that: "It seems that aggression against homosexuality practitioners is only the peculiarity of our species."