According to Jared Diamond, author of “Guns, Germs & Steel” (1997), the races of mankind were shaped more by sexual selection – who we choose to have sex with – than by natural selection – the forces of nature determining how we look. Darwin said the same.
Take skin colour, for example. It seems like a straightforward case of natural selection: light skin is favoured in places with a weak sun to prevent rickets, while dark skin is favoured in the tropics to prevent skin cancer.
That makes sense, but it is not quite that simple – for two reasons:
- Almost no one dies of skin cancer young enough to affect having children. So it does not affect natural selection.
- The amount of sunlight a place receives does not quite match up with skin colour. The general pattern holds but there are plenty of places where the two do not fit, like Tasmania, the Amazon or parts of Africa.
For things like eye colour and hair the match-up is even worse. Why do people in Europe, for example, have blue eyes but nowhere else? The conditions in Europe are not that strange.
Diamond says that physical attraction, what we like physically in a mate, messes things up. Nature matters but sex does too: To have children you must not only live long enough in good health, you must also be desirable to the opposite sex.
That is why women have large breasts, for example: not because babies need it, but because it turns men on and helps to create the babies in the first place.
But what determines what turns men on? Is it something they are born with? Diamond says no: it comes from who you grew up with. We know that from studies done on birds: if a bird is raised by a different race, it will tend to mate with that race even when given a chance to mate with its own race.
It is not just birds. Diamond notices the same thing among Chinese American women: those who grew up among whites tend to marry white even when given a fair chance to marry Chinese. Likewise, those who grew up in Chinese neighbourhoods tend to marry Chinese American husbands even when given a reasonable chance to marry white.
That tells us why most people prefer their own race, but it does not tell us how the races arose to begin with.
Partly it is from the forces of nature, but mostly it is from the founder effect: humans spread across the earth in little bands. When a band settled in a new land, the genes of that band would have a huge effect on those who came after for thousands of years. That is why blonde hair is native to Europe but also to Australia. It was not because of the sun or anything, but because a few people in the bands that settled those places turned out to have blonde hair.
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Interesting post. We can see examples of counterintuitive mating decisions all around us. For example, many years ago possession of a fancy carriage/automobile signified that the possessor had wealth and power, and thus it was a natural attractant. Nowadays, especially in many of our urban areas, a fancy automobile often means that the possessor is a short sighted nacissistic spendthrift, devoting most of his resources to the temporary possession of a depreciating asset, yet, in a Pavlovian sense, the automobile remains an attractant. Thus, perhaps our culture’s preservation of certain memes that once signified wealth, but no longer do so, means that we are selectively breeding certain self-destructive personality traits within our cultural fabric.
The expensive automobile is still attractive to women because the men who own them still have a high chance of being wealthy. Power and wealth will never stop being attractive to women; it’s part of evolution that is still with us.
Though we may be thousands of year removed from the early days of our ancestors, are brains are not. Evolution is a very slow process. We might have mastered all kinds of technology, built cities, and gone to the moon. Still, our brains have not evolved much beyond the hunter-gatherer era thousand of years ago. That’s why we still engage in such short sighted behavior. Does the same tribal mindset apply to mating? It probably does; people tend to be mate with those who look similar to themselves, or to their family. Either that, or they tend to mate with those who are from their same culture. For example, in the states, Indian women rarely will marry a non-Indian man. Muslim women never marry non-muslims.
“because the men who own them still have a high chance of being wealthy”
That’s just it. Most drivers of expensive automobiles, especially in Southern Cal where they’re ubiquitous, don’t own them. They possess them, ususally via a lease arrangement, and usually devoting a substantial portion of their disposable income to them. Often, the car payment will exceed rent for the scuzzy apartment.
In other words, possession of an expensive automobile in a very large number of instances, maybe most, does not correlate with a chance the possessor may be wealthy. In fact, very often it corresponds with a possessor who is a short sighted narcissistic spendthrift — which is a bad candidate for fatherhood.
Well Blanc, tell that to all all the women that love a man with a nice car. Because that stuff apparently works, or else these guys wouldn’t bother. Peacocks use bright and beautiful plumage to attract a mate.
The female peacocks apparently choose their mates largely based on the size and shape of their tales. This way of choosing a mate is just one type of sexual selection: members of one sex mating in disproportionate numbers with members of the opposite sex that possess some “showy” feature. In the humans species “showy” features are often linked to signs of wealth-cars, clothes, house, etc. (weather those signs are real or not is a whole separate issue.)
I recognize that it works. It is indeed a form of Peacocking, abeit one that occurs within Pavlov’s “paradoxical” phase, the area where the subject salivates for the stimulus in the absence of actual food. Consistent with Pavlov’s experiement, decisions based on the automobile are often contra to the interests of the decider.
This goes to Agabond’s post — that sexual selection, even for seemingly arbitrary reasons, can move a social group in an evolutionary fashion.
Abagond:
Some researchers believe “white skin” (pale) in Northern Europe evolved recently due to dietary changes (Moving more from fish and game to wheat and barley which required more vitamin D outside of the diet (such as from the sun) …)
http://www.timesonline.co.uk/tol/news/science/article6814896.ece
Cool. Interesting article. Thanks.
The simulation to the various climates we and our possible offsprings may live or live contributes one of the greatest factors in sexual selection.Many “African Americans” live now in Detroit,Cicago and New York.Many of them for over 40 years,many of them are from from Bantu backgrounds,and most of their offsprings remain in these areas.the climate is to say the least extremely different than the one in Nigeria,Cameroon or Congo,and at the best odds(when no other races might mingle with them),they will gradually adapt to the enviroment,a process whic varies in time.In the beginning,they would appear some minor or “invisible” to say the least traits that would help the new or existing generation to best adapt and prosper in their new enviroments.Not all would obtain these features,some mails for instance may become taller than other,smarter or obtain a stronger immune system to say the least,and the exterior characteristics that support this.There are many factors to refer to all explicitly,but keep in mind that the whole make-up of a population may have a completely different evolution if there are at the first place different than them groups.In the case of Detroit,the population in the next 50 years would be overtly dark brown,if immigration from the underdeveloped african and south asian countries halts.As the years and centuries,would pass them by,their offsprings or they during their lives would obtain more “caucasian” or differnet than theirs features(maybe similar to the once the “native” american tribes have/had in that place).If immigration of dark populations keeps going or an intermarriage with non-dark populations takes place we are talking about different evolution paths and directions.Some species dont necessarily vanish from the face of earth because the rich and smart people are “nazis” and mongers,actually this is the exception.Ofcourse many species wouldnt feel that glad knowing of their declining or non-exist chances to mate,and we are stepping now in a differnet scientific field,psychology. By the way since 1997 genetics had walked a long walk.You should read some new books about sexual selection and genetics.
It’s part Natural selection, part diet, part sexual selection and part mutations(not as in freakish, but as in a change or a mistake in a fetus’s DNA). Skin tone and hair type usually have to do with natural selection and location. Diet can effect body type. An example of this is how Asian foods are usually lower in calories, producing more petite people. Mutations can occur for no apparent reason. If the mutated trait doesn’t cause the animal to perish, it’s often passed down to descendents. Some mutations are benifical (like dark skin in hot enviroments) Some are fatal, some are neutral and do no harm to the animal. Blue and Green eyes are a mutation from standard brown eyes that just so happened to appear in Europe, they were deemed attractive and continued through sexual selection. Blonde hair is another example of a mutation continued through sexual selection. According to the theory of Evolution variation in all life was caused by mutations.
“Diet can effect body type. An example of this is how Asian foods are usually lower in calories, producing more petite people.”
You mean, like egg rolls?
i do not think most white people have blue eyes, most have brown eyes don’t they…it’s just that of the people who do have blue eyes, they’re mostly white…but blue eyes are stll a minority no?