Saturday, August 10, 2013

Great hair ... and how it evolved





Crystal Gayle, American country music singer (source). In humans of Eurasian origin, head hair can grow down to the mid-back and even farther. Long silky hair must have evolved relatively late, certainly no earlier than the last 50,000 years.
 

All of us are born pale, and this infant pallor is striking in otherwise dark-skinned families. Lighter skin also characterizes women, who in this and other ways seem to mimic certain visual, tactile, and auditory aspects of infants (paedomorphic face, soft hairless skin, higher pitch of voice, etc.). Skin tone is, in fact, a key input for sex recognition, particularly the luminous contrast between facial skin and the eyes or lips. This visual cue becomes critical to the mating success of women wherever the supply of mateable men is limited, the result being sexual selection for lighter-skinned women and, thus, a gradual lightening of mean skin color not only for women but for the entire population as well.

Head hair, silkier and longer …

Head hair may have followed a similar evolutionary trajectory. In sub-Saharan Africa:

[…] the majority of African babies are not born with springy tight curls, the African child at birth is either bald or has silky loose curls similar to the Jheri curls. The springy tight curls develop within the first year of life but a few negroid Africans retain their silky hair type for life. (Ajose, 2012)

As ancestral humans spread north and out of Africa, loose silky hair began to persist beyond early childhood and became lifelong. Several changes were involved: faster rate of growth, longer growing phase, increased density, and greater resistance to physical damage (Khumalo, 2005; Loussouarn et al., 2005).

This process seems to have gone further in women, their scalp hairs having higher mean diameter and hence more volume, even in the naturally shorthaired New Guineans (Walsh and Chapman, 1966). Men also tend to lose their head hair, often as early as their 20s. In his review of the literature, Sigler (2011, p. 13) concludes that hair growth rate and final length are somewhat greater in women than in men. It looks as if this hair lengthening was driven by a selection pressure that acted primarily on women.

… but not in all humans

Long silky hair isn’t universal in our species. It exists only in those humans who are native to temperate and arctic regions or in those whose ancestors have back-migrated to the tropics, i.e., tropical Amerindians and Austronesians. Darwin noted "the extraordinary difference in the length of the hair in the different races; in the negro the hair forms a mere curly mat; with us it is of great length, and with the American natives it not rarely reaches to the ground" (Darwin, 1936 [1888], p. 906).

If long silky hair evolved outside the tropics, it must have appeared after ancestral humans had begun to spread out of Africa, some 50 thousand years ago. This point is lost on many paleoanthropologists who attribute this evolutionary change to much earlier events, like the discovery of fire or even a hypothetical aquatic phase of our hominid past.

Whatever the initial cause, there is a consensus, going back to Charles Darwin, that long silky hair is primarily ornamental and due to sexual selection: “we know that long tresses are now and were formerly much admired, as may be observed in the works of almost every poet; St. Paul says, "if a woman have long hair, it is a glory to her” (Darwin, 1936 [1888], p. 906). This view was part of his more general one that “the differences between the races of man, as in colour, hairiness, form of features, &c., are of a kind which might have been expected to come under the influence of sexual selection” (Darwin, 1936 [1888], p. 556).

Darwin believed that sexual selection produced physical differences among human populations through differing notions of beauty. He even raised the possibility that “each race would possess its own innate ideal standard of beauty” (Darwin, 1936 [1888], p. 890). An alternate view, which I favor, is that innate notions of beauty are similar in all humans. To the extent that physical differences among human populations are due to sexual selection, the reason is that this selection pressure has been stronger in some populations than in others (Frost, 2008). 

Why, then, did head hear grow longer as humans left the tropics?

As ancestral humans spread out of the tropics, women found it harder to gather food during the cold season and had to rely more on men to get food for themselves and their children. Polygyny accordingly became costlier for men, with the result that only the ablest hunters could take additional wives. At the same time, men had to roam over larger hunting territories because the density of wildlife was lower. Hunting-related mortality thus rose among young men.

For these two reasons—less polygyny and higher male mortality—the non-tropical zone tended to have a lower ratio of men to women on the mate market. More women had to compete for fewer available men, thus shifting the pressure of sexual selection from the latter to the former. The situation was not unlike that of actresses lining up for a part in a Hollywood movie. When all of the candidates seem perfect for the job, even little details can make a big difference.

One of those details was head hair. Men do notice long silky hair, if only as a visual input for recognition of women or infants, and such noticeability may be a dealmaker in a mate market where women are in excess supply. In such ancestral environments, head hair would have grown longer and longer with each generation.

Was there gene-culture co-evolution?

This lengthening may have been helped by gene-culture co-evolution. In other words, there was a transitional period when women used artificial means to lengthen their head hair. The resulting cultural expectation for longer hair may have favored the mating success of naturally long-haired women.

This hypothesis has support in the apparently ancient time depth of hair lengthening in Africa. As Khumalo (2008) notes:

Africa as the cradle of mankind is likely to have had hair care since the beginning of human existence. Partly because of the oral tradition of passing down history, it is difficult to corroborate evidence of hair care. But probably the earliest form of hair straightening was the molding of hair into shapes using various clays and mud (e.g., indicating the station of a married woman among the Zulu’s). […] Hair was also lengthened with fibers and grasses, much as is done for braids with synthetic extensions nowadays. Although small decorative comb-like structures have been discovered with archeological finds, it is not clear whether original Africans combed their hair or if these implements were purely decorative. Although not written down, fascinating stories of more recent hair care (and hair disasters) are often told by older women about straightening hair using hot stones even before hot combs became available.

West African women invest much time and effort in lengthening their head hair. This isn’t just an obsession of African American women, as some may think: 

“Big hair,” “plenty of hair,” “much hair”—West African communities, including Mende, admire a fine head of long, thick hair on a woman. Both these elements are crucial: thickness and length. Thickness equals increase in the number of individual strands, and the length is proof of strength. Growing such luxuriant hair requires a Mende woman’s patience and care. Because a man’s hair is kept shaved or cut close to the scalp, people say that “men don’t have hair.” Beautiful hair thus is a distinctly female trait; the more of it, the more feminine the woman (Boone,1986, p. 184).

This hairdressing tradition is ancient enough to have spawned myths:

It is known among Mende that all the “water people,” angels, have marvelous hair. The mermaid Tingoi is known by her long, wavy hair and her glamorous habit of dressing it with a golden comb while seated on a rock. A little girl with especially long hair is feared to be in danger of drowning because she will be very attractive to the “water people,” who may think she is one of them and wish her to join them. (Boone, 1986, p. 192)

Among African Americans, women braided and threaded their hair from an early date, whereas men often shaved their heads—an indication that head hair was deemed to be a female characteristic (White and White, 1995).

In sum, hair lengthening seems to be an indigenous tradition whose origins precede not only enslavement in the Americas but also the first contacts with Europeans in Africa. Its purpose has always been to look more feminine … and not “white.”

From artificial to natural

In sub-Saharan Africa, sexual selection was never strong enough to favor women with naturally long hair. This selection pressure would have steadily increased, however, as ancestral humans spread farther north into environments that tended to limit polygyny and boost male mortality.

Head hair may have lengthened during the initial phase of this increasingly intense sexual selection. Eventually, peak intensity was reached as humans spread into the habitable steppe-tundra of northern and eastern Europe—where women had few opportunities for food gathering and where men had to hunt migratory herds of game animals over long distances. It was this later phase that likely produced the diverse palette of hair and eye colors in present-day Europeans, as well as their strange, albino-like skin.

References 

Ajose, F.O.A. (2012). Diseases that turn African hair silky, International Journal of Dermatology, 51 (supp. S1), 12-16
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-4632.2012.05556.x/full 

Boone, S.A. (1986). Radiance from the Waters: Ideals of Feminine Beauty in Mende Art, New Haven and London
http://books.google.fr/books?id=anjOC0zZ6kgC&printsec=frontcover&dq=Radiance+from+the+Waters:+Ideals+of+Feminine+Beauty+in+Mende+Art&hl=fr&sa=X&ei=kTIBUoHfJYfu8ATZ9YGQBw&ved=0CDsQuwUwAA#v=onepage&q=Radiance%20from%20the%20Waters%3A%20Ideals%20of%20Feminine%20Beauty%20in%20Mende%20Art&f=false

Darwin, C. (1936) [1888]. The Descent of Man and Selection in relation to Sex, reprint of 2nd ed., The Modern Library, New York: Random House.

Frost (2008). Sexual selection and human geographic variation, Special Issue: Proceedings of the 2nd Annual Meeting of the NorthEastern Evolutionary Psychology Society. Journal of Social, Evolutionary, and Cultural Psychology, 2(4),169-191. http://137.140.1.71/jsec/articles/volume2/issue4/NEEPSfrost.pdf 

Khumalo, N.P. (2008). On the history of African hair care: more treasures await discovery, Letter to the Editor, Journal of Cosmetic Dermatology, 7, 231.
http://onlinelibrary.wiley.com/doi/10.1111/j.1473-2165.2008.00396.x/abstract 

Khumalo, N.P. (2005). African hair morphology: macrostructure to ultrastructure, International Journal of Dermatology, 44(Suppl. 1), 10-12.
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-4632.2005.02805.x/abstract 

Loussouarn, G., El Rawadi, C., and Genain, G. (2005). Diversity of hair growth profiles. International Journal of Dermatology, 44(Suppl. 1), 6-9.

Sigler, R. (2011). Our Long Hairitage, Bloomington (Indiana): WestBow Press.
http://books.google.fr/books?id=gUEct0Dxt2IC&printsec=frontcover&dq=our+long+hairitage&hl=fr&sa=X&ei=9SsBUvP0OIaQ9gS-xoDQBg&ved=0CDUQ6AEwAA#v=onepage&q=our%20long%20hairitage&f=false 

Walsh, R.J., and Chapman, R.E. (1966). A study of the quantitative measurement of human head hair fibres, Man, new series, 1, 226-232.
http://www.jstor.org/discover/10.2307/2796348?uid=3737720&uid=2&uid=4&sid=21102539793897 

White, S. and G. White. (1995). Slave Hair and African American Culture in the Eighteenth and Nineteenth Centuries, The Journal of Southern History, 61, 45-76.
http://www.jstor.org/discover/10.2307/2211360?uid=3737720&uid=2&uid=4&sid=21102539793897

41 comments:

Anonymous said...

Indeed.

Great hair just means wavy, curly, also known as loose curly that bounce and shine. Like Indian hair, or East African hair (some East Africans are mixed with Arab from what I've read and seen).

It's interesting how African-Americans and sub-Saharan Africans define "light skin". When I think of light skin, I think of all Europeans, Chinese/Japanese/Korean (East Asians) and some Hispanics from Central-South America who have enough (to sometimes high) European admixture.

Yellow-brown skinned women like American actress Tatyana Ali, American model Chanel Iman, American actress Meagan Tandy and East African model Liya Kebede are all several shades darker than the average white, Asian and Hispanic woman (some Asian women are yellow-brown too, like Indian women, but typically they're just yellow, like Vietnamese and Thai women).

Sean said...

Body hair is not likely to be due to sexual selection of women. Europeans have less body hair than other peoples. North Europeans have less body hair than Southern Europeans. (See here).

Short Anagen Syndrome is not being able to grow long scalp hair. Blonde children tend to get it; their hair becomes a good length at puberty.

Europeans have more scalp hair density, and blond(e)s have the most of all with 20% more scalp hairs per centimetre. (See here).

To look more feminine is to look “white.”

Average Joe said...

Great hair just means wavy, curly, also known as loose curly that bounce and shine. Like Indian hair, or East African hair

On what planet? Great hair actually refers to the long soft straight hair that you find in European populations.

Anonymous said...

"One of those details was head hair. Men do notice long silky hair, if only as a visual input for recognition of women or infants"


I prefer functional-random explanations myself i.e. explanations where if you imagined an island where the people were initially randomly attracted to random features of the opposite sex that those people who were randomly attracted to features that provided a reproductive advantage would have more surviving kids and therefore their preference would increase in frequency among future generations while preferences that had reproductive disadvantages would decline in frequency.

Obviously just because i prefer explanations like that doesn't mean they have to exist but i wonder if hair can signal health or fitness in some way so the men who randomly preferred it passed on that preference more until it became fixed?

At that point the degree of sexual selection among different populations and in which direction it was stilted would determine how far the arms race between women over their hair would go.

If even entirely ornamental features are related somehow to general level of fitness then random preference can become an adaptive preference over generations.

Peter Fros_ said...

Anon,

You're confusing phenotype and genotype. Several of the models you mentioned treat their hair so that it will grow longer.

Sean,

Interesting. I wasn't aware that scalp hair density was higher in Europeans.

Anon,

Yes, evolutionary psychologists believe that sexual attraction is driven by indicators of health or fitness. Otherwise, how could such an attraction be maintained by evolution? This is the criticism I have repeatedly heard from people like Don Symons and others.

Do you agree that a mental algorithm can arise for one purpose and then be diverted for another purpose? We see this with mimicry. An inoffensive animal imitates the coloration of a poisonous animal ... and is thus avoided by predators. A similar phenomenon occurs in a context of mate competition. If there are too many females on the mate market, there is selection for females that can "parasitize" useful mental algorithms in the other sex. Some of these algorithms target visual characteristics of newborn individuals and create a desire to seek out and care for such individuals. Other algorithms respond to bright and novel colors by creating a heightened degree of interest.

Evolution is a never-ending story of bricolage and recycling. The original function of a trait is less important than those functions it can later fulfil.

Reader said...

Peter, I notice from the photo of your wife that she has short hair. Do I understand correctly that despite describing the (theoretical) femininity and beauty of long and silky hair, you actually selected a wife who has short and trimmed hair?

In my own observations, I notice that women with short and neat hair are doing quite well attracting partners. For example: Asian women, who tend to keep their hair quite short (shorter than white women), are in high demand among Caucasian white males.

Anonymous said...

The model you propose of ebtering cokder environments leading to more monogamy and higher male mortality due to hunting is interesting. I have never read anything to the contrary because this topic seems so taboo.

Are there intellectual disagreements about this model that you are aware of? It seems like a huge sweeping statement about the whole history of humanity. I would be interested to read more and conflicting views on this.

Anonymous said...

Long haired male rockers, and long haired men in general, are considered to be at least as masculine (or attractive) in general, than baldies or short haired men.

On what planet? Great hair actually refers to the long soft straight hair that you find in European populations

No, he's right, at least for East Indians. Great hair has body, curl and wave, like the Mediterranean and unlike the East Asian and Nordic. Perms are at least as likely to be great hair as straightened hair, and were popular during more sexual periods of our culture.

...

One interesting issue here is that straight hair is the ancestral form, while curled is the derived.

African hair is short, and structurally and constrained to being short, because it is curled (structural weakness is then length inhibiting). So its an interesting question as to why it is curled.

Straight, uncurled hair which is short as in the chimpanzee is a possibility (and if this were so, Peter's hypothesis would have more support), so why does that not obtain in Africa (and other tropical regions)?

Anonymous said...

"Long haired male rockers, and long haired men in general, are considered to be at least as masculine (or attractive) in general, than baldies or short haired men."

If long hair is somehow indicative of general health and fitness then you'd expect it to be attractive in both directions. However how big of an attractant it was in either direction would depend on how significant general signals of health and fertility were for each gender.

For example if how much meat / cattle / land a man provides to feed the offspring is the primary form of male attraction to female whereas the primary form of female attraction is signals of health and fertility then the *proportional* importance is different.

If correct that might lead to men (on average) being say 75% visual in what attracts them and women only 25% (on average).

(Using those numbers just as an example of what i mean.)

That would lead to men and women both being attracted to long healthy looking hair (because it signals health) but differently weighted.

(Plus of course you need to take into account that particular environments may have contra factors for example long hair might have specific disadvantages in jungles for example.)

Peter Fros_ said...

Reader,

Her hair used to be shoulder-length, but she no longer wants it that way because it makes her look like a teenager (which is supposedly a bad thing).

Among white Americans, single men outnumber single women in all reproductive age groups (20 to 40 years of age). This is the main driving force for white American men pairing up with Asian and Hispanic women. It's just the law of supply and demand.

Anon,

It's not a statement about the whole history of humanity. It's a statement about the hunter-gatherer stage (and to some extent about early farming peoples).

There is broad agreement among anthropologists that the polygyny rate decreases with increasing latitude among hunter-gatherers. Fewer have studied latitude and male mortality, but there is no disagreement on that point, at least none that I'm aware of.

But very few anthropologists make the link between those two factors and sexual selection. There seems to be a belief that sexual selection just happens irrespective of the ratio of men to women on the mate market. This in turn has led many people (e.g., Greg Cochran) to reject sexual selection, saying it's a catch-all "unscientific" explanation.

Anon,

Great hair can be wavy or straight. This is a frequency-dependent preference, like hair color. If all of the women you see have straight hair, you'll start to prefer wavy hair, and vice versa.

Hair form doesn't fossilize, so it's difficult to reconstruct the hair form of ancestral hominids.

Anon,

Are you attracted to flashy cars because flashiness indicates that the car is well built?

Anonymous said...

I remember reading a while back that in arctic regions women's bodies would be covered with thick heavy clothing, as opposed to the tropics where their bodies would be more uncovered. That left only the features from the head-up to work with on sexual selection, which is why you get blue eyes and long blond hair. Don't know if it is true. For example, the Inuit don't seem to have evolved blue eyes and blond hair. Are the hunting patterns of the Inuit so different than your ancestral Europeans?

Anonymous said...

"Are you attracted to flashy cars because flashiness indicates that the car is well built?"

I'm not saying ornamentation alone can't be the reason - for example as far as i'm aware breast size doesn't serve any practical purpose above a minimum size - and on the face of it ornamentation seems particularly plausible in the case of new hair colours. I just wonder if there's more to it as well i.e. if all the repeating buzzwords i've heard over the years advertising women's hair products like: "body" "shine" etc are traits that would signal health in their natural form.

Anonymous said...

The photographer Eric Lafforgue (http://www.ericlafforgue.com/) tells of an Ethiopian or Eritrean woman he photographed using a flash. She threw the photo away saying she looked so white it was a shame.
And then there is the social ostracism of albinos. How does that fit into your framework?

Anonymous I said...

Peter,

I think you're on your firmest ground when you discuss issues like these. Hair length and skin pigmentation are directly observable, your thinking is quite straightforward, and the theory fits the facts very well. I think you do less well when you look more at psychological matters - your unfamiliarity with trait psychology and intelligence puts you a bit out of water. But I think you could hammer these sexual selection issues endlessly without ever prompting opponents to cobble together an opposing view that hung together at all. The irony is, of course, that your claims about sexual selection and pigmentation are among the most emotionally difficult things you present. (And it probably only gets worse if other areas of physique, like breast firmness, were to be considered!)

Also, as an aside, I think Greg Cochran is an example of someone "too smart for his own good;" he's clearly brilliant, but many of his claims (e.g. sexual selection being unscientific) are just not well thought out. There seems to be a lot of knee jerk thinking at west hunter, arising from the (not unreasonable) belief that most people are rather dumb. I find it takes a certain wisdom or finesse to be able to know when one is smarter than others, but still avoid lapsing into dogmatism and dismissal of other people's ideas.

Anonymous said...

Can anyone point me to Greg Cochran's arguments against sexual selection?

JayMan said...

Great post, as per usual. :)

I will note that my wife's hair (NW & NE Euro mix) reaches to the middle of her back.

Peter Fros_ said...

Anon,

This is part of the larger question as to why sexual selection of women was stronger in western Eurasia than in eastern Eurasia. In eastern Eurasia, the steppe-tundra zone was farther north and farther removed from the moderating influences of the Atlantic Ocean. It thus suppported a smaller human population and was devoid of human life at the height of the last glacial maximum. As a result, intense sexual selection was less sustainable.

This being said, there is a significant incidence of light hair color and light eye color among Inuit of the western Canadian Arctic. For a long time, this was attributed to Viking admixture, but recent studies have failed to find European admixture in this population. It seems to have been an in situ evolutionary development. See Wikipedia entry on "Blond Eskimos."

Anon,

I know evolutionary psychologists who feel that long silky hair is an indicator of health. In Africa, the evidence points in the opposite direction. AIDS-compromised individuals are more likely to grow silky hair. See the article by Ajose.

Anon,

To begin with, light female skin is already regarded with some ambivalence in sub-Saharan Africa. Lighter-skinned women are appreciated aesthetically but they are not considered to be hard workers, particularly for work that requires lengthy sun exposure. This is a critical factor in societies where women do most of the fieldwork.

In the tropical zone, anti-albino prejudice centers mainly on their inability to work. Their skin is also marred by freckling and the effects of repeated sunburning:

"Albinos, the extreme of paleness, however, are not admired, as their skins lack the essential smoothness and uniformity of texture and their many physical infirmities in any event render them repulsive to normal Ibo."

Ardener, E.W. (1954). Some Ibo attitudes to skin pigmentation, Man, 54, 71-73.

"Albinos, with their flaxen hair and long golden body fluff, their enormous freckles, as if something dirty and brown had been splashed over them, produce an unpleasant impression on European and native alike."

Malinowski, B. (1932).The Sexual Life of Savages in North-Western Melanesia, London: Routledge & Kegan Paul, p. 255

Peter Fros_ said...

Anon and Anon,

To my knowledge, Greg has not written extensively on sexual selection. He just has a strong aversion to it (like many other people, incidentally). When a person develops a strong opinion on something, it's difficult to talk him or her out of it. In the case of European hair and eye colors, Greg will keep bringing up the argument that blue eyes are recessive and thus could not have been favored by sexual selection. Actually, the blue eye allele is not truly recessive. If you have only one copy, a range of phenotypic outcomes is possible, the most common one being green eyes.

Peter Fros_ said...

JayMan,

Thanks!

Anonymous said...

In the case of European hair and eye colors, Greg will keep bringing up the argument that blue eyes are recessive and thus could not have been favored by sexual selection.

Is this in his book "The 10,000 Year Explosion" or on blogs?

Sean said...

Re.traits.

Although men are more likely to have blue eyes while women are more likely to have green eyes, hazel eyes are surely a more common outcome of one copy of the recessive than any kind of green. Green eyes are rather unusual. As I understand it, Peter's theory would predict that the unusual color would tend (I've got green eyes) to occur in females.

I asked Professor Harpending about this at his blog, and I gather C&H think the later DNA evidence rules out what they said in the 10,000 Year Explosion about the ancestors of modern Europeans having been mainly European hunter gatherers. As I understand it they now think the original inhabitants of Europe were completely replaced, and the hair and eye colours may have originated in Kurgans.

Peter Fros_ said...

Anon,

In his comments on this blog.

Sean,

You're right. Among blue eye allele heterozygotes, 16% have blue or grey eyes, 10% green eyes, 47% hazel eyes, and 27% brown eyes.

Branicki, W., U. Brudnik, and A. Wojas-Pelc. (2009). Interactions between HERC2, OCA2 and MC1R may influence human pigmentation phenotype, Annals of Human Genetics, 73,160–170.

Henry and Greg are referring to the mtDNA studies that show a sharp genetic divide between late hunter-gatherers and early farmers in Europe. This would suggest that the original inhabitants of Europe were replaced by farmers of Middle Eastern origin.

The problem with this argument is that the genetic divide actually extends into the period between the earliest farmers and somewhat later farmers. What happened was not population replacement but natural selection.

I discussed this point in an earlier post:

http://evoandproud.blogspot.ca/2012/05/who-were-ancestors-of-modern-europeans.html

But just think. Some Finnish peoples were hunter-gatherers until historic times. The Baltic peoples (Latvians and Lithuanians) were hunter-gatherers until 3,000 years ago. Clearly, those peoples were not replaced, yet they look very similar to other northern and eastern Europeans. Are Greg and Henry suggesting that there was some kind of convergent evolution going on?

Anonymous said...

Green eyes and light brown eyes (sometimes hazel eyes) are common in the Southern Europe (Mediterranean).

Sean said...

Peter, yes they are apparently. I think divergent evolution of the post hunter-gatherer population would have to be invoked to explain the curly red, and golden hair found in west coast Ireland. Ireland (and adjacent areas of Scotland) has far too much red hair for any other explanation to make sense.

Anonymous said...

High latitudes required full body furs/ skins/ which would've certainly suppressed most markers for sex.

Tales such as the Rape of the Sabine Women are but a sliver of history. As seen in the plains North Americans, raiding women and killing rivals was normative for eons of time.

Long hair would've been CRITICAL during such altercations so that females looked like opportunities instead of complications. In this, they'd be a counter-point to facial hair: beards.

It's easy to posit that such raids would certainly involve combat from a distance, so a sexual uniform paid off big, particularly one that works even when facing away and wearing lots of bulky furs.

It's hard to believe that there was any rejection of fertile women in the ancient age. You don't see it in primitive societies. Polygamy solves the problem. Even the not so hot babes are going to see action when when the hotties are swollen with child.

Sean said...

I think Peter's argument is that where the only food source was on the hoof in risky terrain, men often died on hunting trips; surviving men took their pick among women, who had to grab male attention with striking hair. Most men had their work cut out to provide for even one wife and kids, so almost all those trying to practice polygyny might as well have been looking at porn on the internet for all the reproductive fitness they enjoyed.

Peter Fros_ said...

Anon,

Non-brown eyes are common throughout Europe, but the highest prevalences are in the north and east.

Sean,

I suspect that these regional differences developed towards the end of the ice age, when the retreating steppe-tundra became more discontinuous.

Anon,

Our view of "primitive societies" has been influenced by ethnographic accounts from highly polygnous societies in sub-Saharan Africa and Papua/New Guinea, i.e., where the polygyny rate is over 10% of all mated couples. In such societies, there is almost no reproductive wastage among women of reproductive age.

But once the polygyny rate dips below 10%, many women remain unmated during part of their reproductive years. This is especially the case with widows.

Sean said...

Re. the argument that blue eyes are recessive and thus could not have been favored by sexual selection. Could consanguineous marriage have had some bearing on that?

Anonymous said...

There is a remarkable first contact account written by a French cleric centuries past.

Of his many astounding discoveries:

Bear meat (particularly male bears) was prized beyond all other game. It was only huntable in the fall, fully fattened and newly hibernating. One might imagine that they were gassed (smoke) in their dens.

With success, the men -- and ONLY the men -- would feast non-stop for days. More at as an orgy of food. There was one exception for some women, their mothers, just the mothers of the men of the hunt.

Remarkably, the rest of the clan was completely frozen out. They were ejected from the eating lodge -- to survive under open skies and on no food at all, save what they, themselves, could scrape up on their own. (!)

So much for the men providing for their wives and children!

Infant mortality was so high that it amounted to post-natal abortion.

Under feeding the women/ lovers/ kids was not any kind of concern whatsoever. This attitude was universal to that which they, themselves, were born and raised in. EVERY clan operated in this fashion.

Their number one, universal, concern was not finding food -- but keeping other clans off their hunting ground.

'Poaching' as an issue has been recorded by Goodall -- with chimps. It goes millions of years into our past.

The idea that ancient man was a hunter, per se, is entirely wrong, and has led to no end of modern confusion.

While Africans ARE hunters, ancient Europeans weren't. The evidence is overwhelming: our ancestors were TRAPPERS.

Even today, North Pacific tribes feast on netted/ trapped salmon -- and ultra slow moving clams.

Baltic recoveries show that the classic horn style, wicker fish trap is at least 9,000 years old. Since it takes no tools, figure it to be at least 60,000 years old, and picked up from the Neanderthals.

Likewise, herd traps have been spotted (from orbit) all across the Middle East. The ancient way of 'hunting' was to drive the beasts onto a trap/ pit/ enclosure... You can forget bows and arrows as being anything more than harassment fires.

The vast bulk of game was obtained by trapping it.

Even today, the first lessons from any survivalist turn on fire, pure water ... and TRAPS, snare traps being possible without any tools at all. (Well, beyond breaking branches and busting rocks.)

Humanity is just NOT able to run down prey (big game) in a European setting. It's too cool.

It works in Africa -- because we can drive game into heat stroke. That gambit is why Hss is naked in the first place.

Anonymous said...

"It's hard to believe that there was any rejection of fertile women in the ancient age."

Having sex is one thing. Feeding the children is a completely different thing. If you can't feed the resulting children then it doesn't matter how much sex you have.

In an environment where feeding the chidren *requires* male help and where a man physically can't feed more than one family then polygyny becomes literally pointless.

The only question then is do polygyny supporting traits remain dominant but latent in that kind of environment or do dominant monogamy supporting traits develop to reinforce the behavior (with the older polygyny supporting traits remaining in the population but becoming recessive).

Anonymous said...

"Humanity is just NOT able to run down prey (big game) in a European setting. It's too cool."

They could if they could get close enough to throw a javelin into it first as it will slow and eventually drop from the blood loss.

So...animal skins to disguise scent, sneak up as close as possible, get javelin(s) into big game, arrow(s) into smaller game, follow the blood trail. Bingo.

Being tall would be good if the game you were after better suited javelins than arrows, long arms and long legs would make for better leverage. You could throw from further away, less chance of being detected.

For example a Bison, I doubt an arrow would cause enough blood loss to slow it down enough - but a javelin might.

Tall chaps those Cheyenne.

Anonymous said...

The ancient ways are still with us...

But, so culturally shifted as to go unconnected.

======

Over the years, mega-fauna traps have been discovered -- stampede killing falls. Some date back before Hss.

The ancient way of killing a Mastodon was by of traps. Being so big, the scheme was to harass the prey until it fled across a pre-dug series of punji traps. As any survivalist could tell you, traps -- all traps -- work best when the prey is vectored into the killing zone by visual obstructions.

For humanity, the technique was ALWAYS clan based -- as in EVERYONE possible was in on the hunt/ forced game trapping.

This is still true with the San tribe in Africa. The kids and pregnant gals troop right along with the hunt. (!) This was recorded by PBS out of Boston in the mid-1970s. It's out there on Youtube.

There is a consequence: clan communism. The kill(s) were ALWAYS spread communally. It's just that such spreading was also by (caste) rank. In that, it was similar to lion prides. The boys ate first -- all at the same time -- and then it was women's turn. The kids got whatever their mother's permitted/ enabled.

Clan promiscuity was high. Based on their practices, male parentage had to be iffy.

Such cousin-sex was pervasive -- and had to have generated no end of birth defects.

This is seen today in KSA: the WHO reports that an unbelievable 25% of Arab births in that desert land show obvious signs of birth defects.

Arab society hides these embarrassments behind veils and walls.

It's also a HUGE driver for out-mating. Swooping a virgin from a far land is even now deemed (procreative) jihad.

The utter lack of diversity in the ancient gene pool drove countless sex raids. Humanity is, compared to most species, still quite inbred.

One of the dominant reasons for the physical growth of post-war Japanese was the reblending of their own gene pool. Before defeat, most Japanese were mating with their cousins. It was legally impossible to mate far from home.

Red China is undergoing the same dynamic. IQs are ramping up, too.

Inbreeding is also the ultimate driver behind Polynesian royal impulses to marry off local girls with White Englishmen so immediately.

And, of course, it was the dominant reason for the White slave trade in the Dark Ages. Rampant polygamy among the elites had resulted in successive generations (of elites) being massively inbred.

I maintain that most of the 'natural selection' within the human genome was via extremely violent warfare. Further, those unusually attractive females swooped via bloodshed were put to 'maximum reproductive use.'

In effect, they'd be married off to a prince of the conquering clan -- becoming a princess in the bargain.

This theme of female conquest is embedded across human culture. The attributes that would allow a pretty gal to survive while her sisters were slain are not immaterial.

There is a strain of R1B2 that jumped across the Sahara 15,000 ybp. The first assumption has been that young warriors made the trek. That's doubtful. Far, far, more likely is that Sahel raiders swooped down on some hot babes -- and upon their return, knocked them up silly. In contrast, a male warrior crew would've been wiped out. They would've not been in a position to protect their progeny.

In Afghanistan, protecting the females from neighboring tribal sex raids is an obsession. Take a wild guess where and when they picked up that tick.

Bride stealing -- and the dynamics of it -- is the BEST explanation for hyper-selection of beauty traits. No-one is going to haul an ugly babe across the planet. Only 'princess quality' will do. Then, she'll be kept busy making new clansmen -- and how.

So it's a two-fer: ugly babes are liquidated during the raid, the pretty ones are kidnapped. Their bothers and fathers get whacked. And the process never lets up. It's still a dynamic that's of critical concern today.


Anonymous said...

As seen in "Lawrence of Arabia" ancient man engaged in 'clan meals.'

That is, the entire clan ate from the same super sized 'pot.' All of the females would contribute their labor. All of the men would eat first. THEN the women -- and their children would be able to eat -- with the mothers feeding their first-born sons FIRST.

He was her 'retirement package.' With his maturity, she'd be set for life. If she had no sons then she was without.

And, of course, the fertile women were always younger -- on average -- than the successfully mating males. This is echoed today in Hollywood: male stars still are rated sexy thirty-years after the bloom is off a female rose. (55 vs 25)

Really small kills would not get this treatment, the clan feast.

But, the supposition being made is that ancient Europeans were engaged in big game hunting. In such a scenario, no-one is left hungry -- or everyone starves together. The nuclear family is eons into the future.

This clan communism is seen all across the planet with primitive tribes. The casino tribes of California still practice it. Other than the chief and some hangers-on, the entire tribe gets the same slice of the money.(as they define the terms)

Anonymous said...

Anonymous: "There is a strain of R1B2 that jumped across the Sahara 15,000 ybp. The first assumption has been that young warriors made the trek. That's doubtful. Far, far, more likely is that Sahel raiders swooped down on some hot babes -- and upon their return, knocked them up silly. In contrast, a male warrior crew would've been wiped out. They would've not been in a position to protect their progeny."

What are you even saying? Do you not understand how the Y-chromosome is inherited?

Anonymous said...

This post is really grating in how it constantly acts as if non-eurasians can't grow long hair naturally. Well, they technically can't, but the hair of populations like africans, negritos, and australo-melanesians grows outward as opposed to downwards, and can grow in great abundance, with what's usually called an afro. What I don't understand with many of these populations, though mainly in the case of africans, is how so many of them, women included, keep their hair very short or shave it altogether. It's very widespread among africans (except for east africans), and much less common among australo-melanesians and negritos (I've only really seen andamanese cut their hair short, though, and to a lesser extent malaysian negritos.) While these populations typically have less tightly coiled hair than africans, the growth pattern is very similar. And eurasians that DO have curly hair (mainly jews, middle easterners, to a lesser extent europeans and occasionally japanese) which grows outwards don't shave their heads either.

It only really seems to be africans that keep their hair so short, and I really don't know why. It's even seen among more isolated populations, who are also more monogamous, like the khoi and pygmies, even though they're all perfectly capable of growing out their hair. My impression is that "curly" hair can appear equally as feminine as straight/wavy when grown out at a relatively shorter length as compared to straight hair when grown at a longer length down the head because curly hair is more greatly concentrated than straight hair, making it appear more abundant. There's also the fact that long straight hair is more generally going to be going down someone's back, whereas a large afro is going to be much more prominent.

And while I agree that straight hair is intrinsically shinier than curly hair (it's simple physics due to the refraction of light), there's also an issue of proportions- it's possible for hair to appear as too shiny, which is hardly an uncommon complaint if you google, not to mention straight hair can easily become dull, and natural "wavy" hair is technically less shiny than straight hair, even though women all over make their hair wavy.

I fully recognize how vastly more popular straight/wavy hair is on the world stage, and while I agree with many of your writings on beauty in the long run, this post is just incredibly flimsy, especially in face of basic things like how short straight hair is hardly unpopular or unfeminine, and also with men wearing long hair (though for this to work, I'd say a man has to look masculine). You seem to have almost a naive fixation on tying in eurasian features with sexual selection and hyping them up to such a degree. I really don't think there's any genuine reason why curly, african type hair when grown out can't be seen as attractive as straight hair. You really haven't outlined any good reasons why.

Anonymous said...

I shouldn't have said you haven't outlined any good reasons why, but they aren't very convincing- I feel you give a simplistic treatment of curly hair, such as never highlighting how it can grow it out, along with a number of other things. Straight hair is also predominantly recessive in humans, and I'd question the inherent feminine selective value of a trait that works like that. Not to mention when you look at many human populations in question, things become more muddied- while jews might not be a very good counter point in face of their peculiar history, many middle easterners show relatively high frequencies of curly hair, and even southern europeans do. Curly hair wasn't uncommon on ancient greco-roman statues of women. Not to mention that many dark skinned, tropical, non african polygynous populations exhibit curly hair that is quite wavy or much straighter than africans, and the highly monogamous khoi have the most tightly coiled hair of all.

And in regards to Sean's first post, where do you get the idea Europeans have less hair than other peoples? Maybe less than other caucasoids, but europeans are generally hairy and certainly much hairier than africans and asians.

And Frost, where have you heard that albinos are disliked mainly because of their inability to work? I imagine that's a sizable factor, but disparaging of albinos seems to primarily focus on the ugliness of their pale skin from what I've seen.

Anonymous said...

It's been a couple months, but a few other things regarding a more recent post in relation to this one: http://evoandproud.blogspot.com/2014/02/slc24a5-reply-to-greg-cochran.html

You're right that ethiopian religious art often depicts lighter skin tones than the average Ethiopian, but I believe this ethiopian religious art is primarily made by the Amhara, who inhabit the northern reaches of the country. I some days ago came across a page that depicted averages of north, south, east and western ethiopians, and northern ethiopians were the lightest of all, and didn't seem much different from the range in ethiopian church art.

And in relation to the post about Eric Lafforgue's photography, ethiopians and eritreans do not have that pattern of female work division and are generally lighter than other africans.

And going back to the ethiopian church art, you might notice that the majority of the time, people, even angels, whether male or female, are depicted with afros- just google "ethiopian art" or "ethiopian church art". Doesn't really square with your naive, ethnocentric fixation on straight hair being indisputably the most attractive, which of course, unlike tropical hair, can't grow out.

Anonymous said...

Rereading this post again, I think I was too kind on it in the past. It's completely moronic and reflects an astonishing lack of awareness and knowledge of basic human variation on your part, and it's even worse for the fact this is largely a reiteration of a post of yours from 2008, showing you've learned absolutely nothing since then (but it begs asking why how you'd go throughout your life to write something so ignorant and misinformed.) Now, it'd be one thing to argue that the slower growth and shorter growth phase is consistent with your theories of sexual selection (though european hair grows more slowly than asian hair), or how women wearing short hair being so widespread across africa might reflect cultural norms that are possibly consistent (but then there's all the other populations with similar hair, and khoisan, whom you hold up as an example of monogamy lightening skin color, have the most tightly coiled hair of all populations, and seldom grow it out), but to the point you'd honestly claim that not only that these populations cannot grow abundant hair, but that afro-type hair cannot grow in abundance, and that only hair that grows downward is inherently feminine/attractive is absolutely breathtaking.

Your only citation that african hair can't grow more than a few inches is Darwin, and your citation on new guineans says nothing about what length it can grow. And for the record, here's some of those "naturally short haired" new guineans:
http://afroglitz.com/tag/new-guinea/
http://37.media.tumblr.com/tumblr_ldy4a1JmCI1qce4odo1_500.jpg
http://i.imgur.com/vsk0i.jpg

And here's other melanesians:
http://i.gyazo.com/8110ef6b9d31f4b828bfe70134757a66.png
http://i.gyazo.com/fbadeb9d9e6af6757fb88baba1ef9214.png
http://archives.pireport.org/archive/2009/August/heroes.jpg (note bougainville islanders are the darkest melansians.)

I could go on, but you don't have to look far at all to find pictures of papuans/melanesians with abundant hair. Yet you still wrote something as absurd as papuans being "naturally short-haired". And I can't find too many clear instances of ones with coiled hair straightening their hair (they

And outward hair styles have hardly been considered unattractive or unpopular in east asian/european cultures (contrary to your fixation on only long, downward hair being attractive):
http://i.gyazo.com/4c075547b804f32fca3aec14a8b97f52.png
http://i.gyazo.com/ab5cd431a0345da83d39f493043d2e5e.png

It's also remarkable just how many of your readers don't call you out on any of us- like Sean, one of your neurotic fanboys (along with Tod and Ben10) throwing in how "to look more feminine is to look more white" because of northern europeans having less body hair than "other peoples" (I assume he means other caucasoids, which isn't saying much) and blondes having more hair on their scalp- I could say a lot about that, but for the record, there's not a word about this leaving white men more feminine (although he seems to possibly accept this to an extent judging by his comments about Danes in "Survival of the Cutest"), and it turns out red heads have the fewest hairs: http://books.google.co.uk/books?id=4GMbPmmWPTsC&pg=PA210&dq=hair+density+blondes&hl=en&sa=X&ei=UMNMU7eNOIeU2wWzuYCwDg&ved=0CDIQ6AEwAA#v=onepage&q=hair%20density%20blondes&f=false

Anonymous said...

"And I can't find too many clear instances of ones with coiled hair straightening their hair (they"

The rest of this was meant to remark on how papuan women, for the most part, seem to grow out afros as opposed to lengthening it downward for the most part. But, the fact the Mende and some other west african groups admired downward hair as opposed to typical afros is more good evidence that these people are incapable of growing abundant hair, and african-american obsession with straighter hair has nothing to do with white cultural influence.

But what else is there to really say- this post and how fundamentally detached from reality (and how emblematic it is of you wanting to vigorously tie in eurasian features and human variation in general to sexual selection) it is should be apparent to just about anybody, but apparently not you or any of your brainless commenters.

Anonymous said...

A couple other things- I didn't realize your ideas about head hair here were mentioned in your 2008 paper on sexual selection. They're almost word for word the same as in here, and you use the same exact references- Darwin and an unrelated paper on Papuans. So it begs another question- how was this able to pass peer review?

And on the topic of the ethiopians, look at the royal family sometime- even the women sported afros, which includes Menen Asfaw, the queen. But with how long you've gone without recognizing such a basic observable fact of human variation, I don't know how much that will help.

Peter Frost said...

Anon,

I don't mind being called "moronic." I do it mind it, though, when a commenter makes abusive remarks about other people. This was why I deleted the one where you made remarks about Jayman's ethnic origins.

I understand why some commenters prefer to remain anonymous. Anonymity, however, is not a licence to publish insults. Is this the way you talk to your classmates whenever you have a disagreement? If so, how many teeth do you have left in your mouth?