According to Darwin's theory, natural selection is the engine of evolution. Individuals who have a relative advantage in a given environment, they will have more viable offspring, which will pass their characters on to the next generation. What is less known, is that this idea, of natural selection, and older, preceded the appearance of the book "The Origin of Species". There were others who expressed it, even related to evolution (v. Theories of evolution). It was also simple, because farmers have been creating plant varieties and animal breeds on this principle for thousands of years. Why wouldn't nature do the same?
But Darwin had a great original idea: sexual selection. In "The descent of man" he talks about it in our own species. In full Victorian era, he points to the fact that women make sexual selection, as in other species all the female sex has this heavy obligation. Women choose their partners, that's the point. Why? Dawkins explains in 'The Selfish Gene', which he then nuances in "The Blind Watchmaker". He says that the sex that invests more in reproduction "sells" its participation in this act more expensively. Females invest more in their eggs, which are much larger, so they choose their partner, says Dawkins. It is in their best interest not to waste their eggs by combining them with any genes. They must choose only the best genes available. In "The Blind Clockmaker", Dawkins nuances this idea, but in the end the results are the same. Even if the eggs are large, and the spermatozoa are small, spermatogenesis is an energy-consuming process. But the number of eggs is less than that of sperm. For her an egg is precious, so they have to invest it better.
From peacock tail to generosity
But if natural selection has been talked about a lot, sexual selection entered the discussion much later, in the 20th century. That's right, selection has generally been difficult for biologists to digest, since the end of the 19th century. It prevailed only once with the modern synthesis, the theory of evolution that brings together the mechanism of natural selection with the new discoveries of genetics, that is, in the middle of the 20th century. Some authors have wondered why sexual selection has been somewhat neglected for so long. The idea was circulated that the woman's status was "to blame". female (BITCH) it had a very important biological role, which was difficult to accept in those social conditions. However, as other authors point out (idea to which I subscribe), this idea was simply harder to grasp. It is true that its imposition somewhat coincided with the momentum of the feminist movement, but it probably also coincided with a better understanding of some phenomena. Any scientific theory is very difficult to understand by others than its author, therefore it is more difficult to impose.
Why is this idea so important?? Because it explains phenomena impossible or difficult to explain by natural selection. As Tor Norretranders points out (with a cut, which is read o with umlaut) in "The Generous Man" (Public publishing house 2008), if natural selection is conservative, sexual selection is very creative. It fixes characters that don't seem essential to survival, more, which seem harmful or even very harmful to the survival of that individual. Sexual selection is used to explain many characters that are difficult for Darwinists to explain, from the peacock's tail to human intelligence, the giant brain and even human generosity.
The classic example is the peacock's tail. The longer a peacock has a tail, he is more desired by females, even more, female peacocks they mate with lay more eggs than those mated with males with more modest tails. Why? Both Dawkins in "The Blind Clockmaker", as well as Norretranders (who is not a biologist) I'm talking about the hypothesis, contested in the 70s, when it was released, but which was later imposed, to him Zahavi, an Israeli. Zahavi introduces the idea of the handicap principle. That is, if a peacock has a very long tail, it is exposed to predators more than the short-tailed ones, more, he consumes more to maintain this adornment, he also has problems flying. However, through that long tail, he communicates to the females that despite these handicaps, he is alive, so his genes are very good, so he deserves to be the father of some cubs. From here, the assumptions are chained. What important genes would they signal?? For example those of resistance to different parasites. There are resistance genes for a particular parasite, but the more such genes an individual has, which confers resistance to various parasites, the longer his tail is. Answering other problems related to this hypothesis, for example how do peacocks know what to choose, the idea was advanced that if they have long tail eyelashes, I choose males with long tails, preserving and reinforcing their phenotype in the next generation.
Since sexual selection came into the sights of evolutionists, it becomes the solution to almost all Darwinists' problems. Sexual selection explains everything, from the absence of the penile bone in man, like other primates, which would allow an erection without assistance, the one that would constitute an indicator of the male's health (example found in Dawkins) to altruism, artistic creation, language etc.
What is the peacock thinking?, but also other females?
Agree with the sexual existence, which indeed explains the existence of characters that not only do not help survival, they can even put her in danger. However, to believe that such subtleties exist in the peacock's brain, which is nothing but a hen with long hair (the definition is not mine)? Birds see very well, much better than primates, we are not talking about other mammals. I respond well to visual stimuli. I know that at the sight of the male, at least to the dove, ovulation occurs. I don't know about the peacock, but if so, when he sees a stronger sexual stimulus, ovulate. The stimulus would be the queue. The peacock would do nothing but discriminate stronger stimuli from weaker ones. A bigger tail is a stronger incentive.
Consider the extraordinary variety of preferences of females with highly sophisticated brains: human females. And to the "usefulness" for the new generation of the genes of males like Passaris or Nica, really want after they became famous. Women need stimulation, no matter where they come from or how strong they are, from the outside, bani, succes, to affective subtleties, a principle, however, would be that men communicate better, no matter what, would be the women's favourites. If you don't communicate, you don't have. The more you communicate the better, no matter what, you have more chances. How many women prefer accountants with gray personality, glasses and depression?
Regarding Zahavi's hypothesis, i think it says more about him than the peacocks. Men are good at seeing the competition (they are obsessed with competition), women to see the communication. I remember that a few years ago, in the discussion with a man who is my relative, he hypothesized that men prefer women in heels because they can do something special, they are stronger than others. He did not know about the handicap principle, how he doesn't know even now, but this statement is something like this hypothesis. Perhaps Zahavi was right here, when he said that women want what they have, they see the communication they are so good at. But he was referring to the fact that if there are long tails in a peacock's family, they prefer long tails. But what about the fear of inbreeding? Women are known to dislike their first cousins. Personally, any man I see a vague physical resemblance to me turns me on. Women want and see communication, men see competition. Everyone is satisfied. That's the difference between men and women (in explaining this phenomenon).
But the probability is that a woman has a better understanding of how sexual selection works simply because she is more involved in the process. Tor Noretranders says in "The Generous Man": "Make an effort and you'll have sex!” More specifically it would be “Send strong signals and you will be preferred by females!” It also applies to men? Even worse. Probably the difference between males and females is that they are more subtle, accepts more varied and bizarre signals, instead the male brain, programmed to respond strongly to "classic" sexual stimuli, simply blind in their presence. That's probably why most men can't get past the charms of a knowing Barbie doll 500 of words, and give a chance to a cultured and sophisticated woman like Zoe Petre. Men also have a greater power of concentration, which makes them lose sight of collateral aspects, in this case it narrows their interest in the qualities of women.
Even if the ideal of beauty is varied in different cultures and eras, it must be physical first. What does beauty mean?? The most accepted hypothesis is that it means youth, so fertility. I didn't do a study, but I would be curious what men prefer, a peasant girl full of health, but totally unkempt or an elegant one who hides her dark circles with make-up? In traditional cultures, people, regardless of gender, they are even more "artificial", they use a lot of makeup and jewelry. What does beauty mean?? First of all, sexual receptivity. When a woman is arranged one way or another, it conveys the message of receptivity. Some do it naturally, mime "arrangement". But why do prostitutes wear so much make-up and dress so provocatively??
Why it's good to preserve sexual selection? Because sexual selection, besides some pointless characters, indeed it ensures the transmission of useful characters such as generosity, different talents, but also ensures the development of culture. Women make a society. The West is what it is because of women. Beyond the fact that society does not lose the workforce of half the population, Women's "tones" determine complex sexual selection, with a diverse cultural influence. The freer women are, more independent material, they will prefer to a lesser extent simply the necessary material security, but all kinds of bizarre things, many useful for the development of culture.
Yesterday they came true 150 years since Darwin's "On the Origin of Species..." appeared.
