Sexual selection as a genetic disease

In this post, I want to discuss about the prejudice of people against black skin. A person need not be a racist to consider fair skin as beautiful and black skin as ugly. Part of this prejudice is cultural. Most of us are raised in cultures which glorify the fairness of skin as a vital element in the beauty of a person. But, can this prejudice be explained entirely in terms of faulty upbringing ? We cannot tell for sure. I would like to consider the argument that part of this prejudice is rooted in our genes.

When Homo Sapiens evolved out of apes, they lost their fur. This happened in Africa 60,000 years ago. With naked skin, humans were exposed to the harshness of the ultraviolet rays of the sun. Natural selection forced them to evolve a pigment, called melanin, as a means of protection against this. This turned the skin of humans to black. When they started migrating out of Africa, all humans were black. So, how did fair skin arise in the first place ?

When humans migrated to colder climates, they lost their need for melanin. However, the rule of nature is that attributes which have no evolutionary disadvantage just keep staying. No force of natural selection explains why black skin could be a disadvantage. So why did fair skin arise in the first place ?

Some people think fair skin arose as a need for camouflage within sheets of ice – this theory is quite humorous, but nothing more. A more plausible answer lies in the force of sexual selection.

When Darwin proposed his theory of evolution, he stressed on natural selection as the most important force determining the metabolism of animals and plants. However, there are several things that cannot be explained by natural selection alone – the colorful tail of a peacock, for example. As Darwin put it, “the sight of a peacock’s tail just makes me sick”. This bright tail gives no advantage for the peacock in terms of gathering food or fighting rivals. Instead, it is just a blaring invitation for predators to attack the bird. The reason why this tail arose is a big dilemma – even to this day.

To explain this, Darwin proposed a different force of evolution, termed as sexual selection – female peahens prefer peacocks with bright tails. So a peacock with a bright tail gets higher reproductive success even though it puts it at a higher risk from predators. But this still doesn’t answer the question – why should females prefer such a stupid attribute ? Biologists still keep debating about this.

One of the most promising theories we have now is called the “handicap theory“. The bright tail of the peacock is essentially a handicap. When a female eyes at such a tail, it thinks “this male has to be extremely strong and powerful in its other attributes to keep surviving with such a handicap”. Thus the tail becomes a reproductive plus point for the male.

Sometimes, even if there is no logic for selecting a mate, this gets hard-coded into the genes of the female under a theory known as the “sexy son hypothesis“. When a female looks at a crowd of females using a logic to select mates, it selects its potential mate using the same logic. That is, it selects a peacock with a bright tail because it knows that its offspring will have a bright tail too, and thus, have higher reproductive success.

Darwin reverted to the force of sexual selection to explain the several useless attributes that arose in animals and plants. He also opined that the differences of features between several human races could also have been due to sexual selection, because, they obviously provide just no evolutionary advantage under nature. This could be the same reason for the rise of fair skin. In humans, due to monogamous relationships, the pressures of sexual selection are applicable both on males and females.

Sometimes, sexual selection is in logical agreement towards natural selection. That is, females prefer attributes which are essentially tell tale signs of higher survival skills – such as the long antlers of a deer or the deep roar of a lion. Males prefer attributes which are signs of higher virility in females – such as youth and a healthy body. In humans, these preferences can be observed in females getting rated according to the size of their breasts and their bottoms – essentially signs of good health and virility.

At other times, sexual selection gets extremely illogical, such as the preference for a fair skin. This can be explained only through theories such as “handicap theory“and “sexy son hypothesis“.

Fair skin is essentially a handicap in tropical climates, and if a person survives with this handicap, that is only because of greater immunity and strength otherwise. In the tropics, this pattern could not be sustained for long because the trade off between survival and reproductive success is tilted towards darker skin. However, as humans migrated to colder climates, this handicap ceased to be as severe as it used to be. This provided a trigger for the onset of sexual selection, with people preferring fair skin as a mating-choice and the fair skinned people not dying as badly as they used to die in the tropics. The pattern of fair skin got repeated in the population through the “sexy son hypothesis“.

Amongst fair skinned people of today, generations of evolutionary corroboration has etched this prejudice hardly into their genetic make up. So viola, we have a notion of beauty defined in terms of the colour of the skin. Not surprisingly, this standard of beauty is not present in the populations of Africa which have not been subjected to the same pressures of sexual selection. In India, there had been a high contamination of the gene pool with fair skinned people. It is not surprising that people in India have a highly distorted view of human beauty.

The journey of the human migrations can now be studied directly through genetics. It is the gene haplogroup M, (specifically M9) which has arrived successively in India over periodic waves of settlements. These people have spent enormous amounts of time (ranging from 30,000 to 50,000 years) in colder climates to be subject to the pressures of sexual selection. They are of the same stock as the majority of the Europeans and probably looked the same – pale and blond. When they descended into the subcontinent, a vast majority of them could have died at a very early age due to the disadvantage of fair skin. So, a second series of evolutionary pressures, this time from natural selection, turned their hair and skin darker. After a period of 10,000 years running to this date, the fairest of the Indians could not have been as pale as the Europeans, even without the interracial mating that happened in India. But the prejudice against dark skin was subject to much longer periods of evolutionary pressures (5 times longer), so it continues to this day.

Is sexual selection bad by itself ? No. How can one hate the tail of a peacock or the song of a cuckoo ? Amongst the brutal forces of natural selection, these elements add some spice and variety. But, at best, they can be described only as cute. When taken to excess, these prejudices become vitriolic. For example, when the prejudice for fair skin overrides the prejudice for large breasts, it should be termed as a genetic disease – as it results in lesser reproductive success for an individual. I think it is time that we honestly asked ourselves the question – how many of us are subject to this genetic disease.

It is even more pathetic when these prejudices enter the very fabric of culture – when they get associated with everything that they have nothing to do with. For example, it is outright stupid to associate fair skin with wisdom or creativity. This turns the whole problem into a cultural disease, which is affecting the mentalities of a huge number of people currently. Under the guise of free speech, these poisonous rantings are continuing to spread. Nobody seems to be learning any lessons from history.

As human beings, if there is something that we possess that we should be proud of – it is our capacity to think and reason. The human brain is a marvellous product of evolution and the pride in this should unite every single human being. Next to this, every other attribute that we possess is marginal and negligible. But, we still obtain no respite from racism and its associated diseases.

In order to understand the gravity of this problem, let’s observe popular culture. How many times has a savage barbarian be portrayed with blond hair ? Why don’t we see images of blond people dancing to drum beat and performing human sacrifice ? How many times has devil or a demon been portrayed with blond hair or fair skin ? As long as this notion seems unthinkable, it means that the grip of the cultural disease is quite strong on our society, just waiting to explode through physical acts of racism such as murder and genocide.