Saturday, May 12, 2012

Survival of the cutest?


Please take care of me! (source) Child neglect is common in Papua New Guinea, even in regions where food is relatively abundant. Did juvenile hair color become lighter as a way to elicit maternal care? 

If we exclude people of European descent, blond hair is most common among the natives of Oceania, specifically within a zone stretching from central and western Australia, through Papua New Guinea and into Melanesia and nearby islands. This coloration is due to a genetic variant of TYRP1 that is rare or nonexistent outside Oceania (Kenny et al., 2012).

Among central Australian Aborigines, blond hair varies by age and sex:

Up to 10 years of age the color distribution is approximately the same in both sexes at about 85% “fair” to 15% “dark.” Over the age of 11 years it is difficult to find a “fair” male while female “fairness” falls off more gradually.

[…] In the males the onset of darkening becomes apparent from about the 8th year. In adolescence the hair ranges from medium brown to black (observations in this group are very limited) while beyond 20 years practically all are in the “dark” category. […] In the females darkening becomes definite only after about the 20th year, and even in old age does not often exceed light brown. (Abbie & Adey, 1953)

We see the same age and sex pattern in Solomon Islanders:

An interesting hair phenotype that is sometimes seen in Island Melanesia (as well as among Australian Aborigines) is “blondism,” in which individuals exhibit the characteristic darkly pigmented skin of the region while also having blond hair. This trait was most commonly observed in children whose hair generally darkened around puberty (Robins, 1991). However, in some cases, blondism persists into adulthood, although the hair appears somewhat darker than what is seen in children (Norton et al., 2006).

This is similar to the situation in Europe, where blond hair likewise is more common among children and women (Shekar et al., 2008; Steggerda, 1941). Among Europeans, however, blond hair is much less specific to juveniles, being maintained throughout life in most individuals.

Origins and adaptive value

How did this “Oceanic” blondism come about? The evolutionary path may be analogous to that of European blondism.

European women naturally have hair that is more brightly and diversely colored (Shekar et al., 2008; Steggerda, 1941). This is consistent with a need to attract prospective mates, since bright and/or novel colors are more likely to be noticed and remembered. Most alleles aren’t sex-linked, so this kind of sexual selection would have spilled over on to European men, changing their hair color as well (Frost, 2006; Frost, 2008).

All of this implies that ancestral European women faced a competitive mate market. At higher latitudes, too many women had to compete for too few men, especially among hunter-gatherers. On the one hand, hunting distances were longer on average, thus increasing male mortality. On the other, men were less polygynous because of the higher costs of provisioning women and their offspring, especially during winter. This excess of females over males in the mate market was greatest on the continental steppe-tundra that covered most of Europe during the last ice age. Northern Asia also had steppe-tundra, but only in arid regions farther north where human occupation was not continuous, particularly at the height of the last ice age (Frost, 2006; Frost, 2008).

In equatorial Oceania, the evolutionary path may have been both similar and different. As in Europe, there is an aesthetic preference for blond hair:

In Samoa, all fair hair is considered 'ena'ena, a word that is usually translated as brown, although when English-speaking Samoans use this term in reference to hair, they typically gloss it as 'blond'. This makes sense since, when one is bleaching Polynesian hair, it goes through a series of reddish- brown shades prior to arriving at blond, and even then retains a reddish hue. When describing hair, Samoans specify the actual shade of 'blond' by using certain modifiers with 'ena'ena, such as 'ena'ena manaia, which literally means 'really nice brown hair', but which refers to a very fair reddish colour.

The hair of female spirits is most commonly said to be 'ena'ena manaia, and they are wont to decorate it with a red hibiscus (Mageo, 1994).

But what is the adaptive value for young children? They are, after all, the ones who most often have this hair color. What kind of selection pressure could have favored blond children?

One possibility is child neglect. Papua New Guinea has a relatively high rate of child malnutrition—35% on average, with some regions having rates as high as 78%. Yet malnourished children are found in areas that have an apparent surplus of food. Lepowsky (1987, p. 75) notes that “the reported pattern of child malnutrition did not follow environmental or ecological patterns but cultural ones.” The ultimate cause seems to be “maternal detachment”:

These women take a guarded attitude toward infants, extending the greatest amount of their affection and parental care toward children who are physically strong and who survive the first couple of years of life. (Lepowsky, 1987, p. 78)

For this reason, child naming is delayed for a few weeks after birth, and the ritual thanking of the father’s kin is delayed for about six months. Mothers take for granted that their offspring may not survive this period.

Thus, in equatorial Oceania, child survival depends very much on the degree of maternal attachment, i.e., the mother’s fondness for her child. Has this factor favored “cute” features, like blond hair? Is blondism a child’s way of eliciting more maternal care during infancy?

References


Abbie, A.A. & W.R. Adey. (1953). Pigmentation in a central Australian tribe with special reference to fair-headedness, American Journal of Physical Anthropology, 11, 339-359.

Frost, P. (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

Frost, P. (2006). European hair and eye color - A case of frequency-dependent sexual selection? Evolution and Human Behavior, 27, 85-103 http://www.sciencedirect.com/science/journal/10905138

Kenny, E.E., N.J. Timpson, M. Sikora, M-C. Yee, A. Moreno-Estrada, C. Eng, S. Huntsman, E.G. Burchard, M. Stoneking, C.D. Bustamante, & S. Myles (2012). Melanesian blond hair is caused by an amino acid change in TYRP1, Science, 336, 554.

Lepowsky, M. (1987). Food taboos and child survival: A case study from the Coral Sea, in N. Scheper-Hughes (ed.) Child Survival: Anthropological Perspectives on the Treatment and Maltreatment of Children, (pp. 71-92), Springer.

Mageo, J.M. (1994).  Hairdos and Don'ts: Hair Symbolism and Sexual History in Samoa, Man, New Series, 29 (2) 407-432

Norton, H.L., J.S. Friedlaender, D.A. Merriwether, G. Koki, C.S. Mgone, & M.D. Shriver. (2006). Skin and Hair Pigmentation Variation in Island Melanesia, American Journal of Physical Anthropology, 130, 254–268.

Shekar, S.N., D.L. Duffy, T. Frudakis, G.W. Montgomery, M.R. James, R.A. Sturm, & N.G. Martin. (2008). Spectrophotometric methods for quantifying pigmentation in human hair—Influence of MC1R genotype and environment. Photochemistry and Photobiology, 84, 719–726.

Steggerda, M. (1941). Change in hair color with age, Journal of Heredity, 32, 402-403.

41 comments:

Sean said...

Hunter gatherer mothers don't have the resources for 'extra' children. With agriculture the mother's attitude would be the crucial factor in whether marginally viable children are invested in. I have to wonder why natural selection would not produce a greater tendency to care for less viable children, after hundreds of generation of agriculturists. Why would the care eliciting hair color be necessary?

Anonymous said...

Since we're on neoteny, this might interest you Peter:

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0035917

"Main craniofacial changes indicate that Europeans differ from Southern Africans by increasing facial developmental rates and extending the attainment of adult size and shape.

Since other studies have suggested that native subsaharan populations attain adulthood earlier than Europeans, it is probable that facial ontogeny is linked with other developmental mechanisms that control the timing of maturation in other variables.

Southern Africans appear as retaining young features in adulthood. Facial ontogeny in Europeans produces taller and narrower noses, which seems as an adaptation to colder environments.

The lack of these morphological traits in Neanderthals, who lived in cold environments, seems a paradox, but it is probably the consequence of a warm-adapted faces together with precocious maturation."


Interestingly they found 2 principal components associated with a neotenous shape in their analysis and which differed between the ethnic groups.

On the larger, Europeans started out the same as the Africans, but were more developed (less neotenous) in shape (although not larger in size) at every single age after that. On the smaller, Africans started out more developed and ended up more developed.

So Europeans begin life with a more neotenous face shape and end maturation with a more adult shape. Europeans seem to be postdisplaced (less mature at the start of growth, end growth later) and accelerated (face shape develops faster).

(There was no differentiation on facial centroid size - i.e. face size. Of course there were no mandibular measurements included.).

This seems like it would be a Caucasoid wide pattern, since it distinguishes the Negroid from Caucasoid face shape to a large extent.

Insightful said...

Another fascinating thing about Melanesians is that their hair texture ranges from tightly-curled (like sub-saharan Africans) to loose curls. Like with regard to australian aborigines, some have straight hair like in this picture:
http://wdict.net/img/australoid+race,1.jpg

or downright afro hair as in this picture of one of the last Tasmanians:
http://upload.wikimedia.org/wikipedia/commons/4/4d/William_Lanne.jpg


I just find the phenotypic diversity in this seemingly limited part of the world astounding!

Anonymous said...

I thought the blonde genes in Caucasians come from the Finnic-Ural gene pool that originates from Ural region.

Insightful said...

@theslittyeye
Apparently, different genes for blondism arose separately more than once, and who knows how many times…

Bren10 said...

Darwinism =
'Survival of the Survivaliest'

Peter Frost said...

Sean,

I'm not sure why maternal detachment is so prevalent in Papua New Guinea. So far I haven't found any more material on this point.

Anon,

It's an interesting paper. But doesn't it run counter to the idea (popular around a century ago) that Europeans are more neotenous than Africans? There was a lot written on that theory by people like Bolk. Prognathism, for instance, was interpreted as an adult face pattern that never develops in Europeans because their facial development is permanently stalled in infancy.

I'm frankly skeptical about attempts to create a unified theory of human biodiversity. To me, it seems counter-intuitive. The only unified theory is the theory of natural selection itself.

Insightful,

Australia probably had several waves of human settlement. The Tasmanians are thought to correspond to one of the earlier waves.

theslittyeye,

Europeans have a very large number of alleles for hair color. MC1R has at least 7 phenotypically distinct alleles that exist only in Europe, and there are apparently hair-color alleles at other gene loci.

Blond hair itself is not a uniform phenotype. Blondism is probably produced by several different alleles.

Bren10,

Darwinism =

If you survive and reproduce, you've got something that the others don't.

Anonymous said...

It's an interesting paper. But doesn't it run counter to the idea (popular around a century ago) that Europeans are more neotenous than Africans? There was a lot written on that theory by people like Bolk. Prognathism, for instance, was interpreted as an adult face pattern that never develops in Europeans because their facial development is permanently stalled in infancy.

Peter,

In the paper, the African sample did show the increased level of acceleration (opposite of neoteny) in the second PC, which is a PC associated with prognathism, while the first PC wasn't. This matches up with Bolk's ideas.

However, in terms of shape, Africans are less neotenous when we look across all PCs, as Europeans are more accelerated on the first PC, which is of larger size than the second PC, and the subsequent PCs lack racial associations (which facial size is similar between groups).

The greater brain size of the Europeans might save the neoteny theory a little, but frankly by then we're far enough from neoteny (there is no real unidirectional pattern) that we can't really call the patterns neoteny with a straight.

I'm frankly skeptical about attempts to create a unified theory of human biodiversity. To me, it seems counter-intuitive. The only unified theory is the theory of natural selection itself.

Yes, I agree - frameworks where HBD differences are placed on a single axis - in this instance the heterochronic neoteny axis of the Bolk-Montagu-Gould tradition - with groups being assigned a place on this axis, generally seem overreaching. As much as heterochrony does have its place.

Very few people informed by the neoteny view of human evolution would be able to perceive Neanderthals as neotenous on this characteristic element of facial shape (which they are, as on other aspects of cranial shape http://tinyurl.com/c2xuupj - "Newborn Neandertals and newborn modern humans have elongated braincases, and similar endocranial volumes.
During a ‘globularization-phase’ modern human endocasts change to the globular shape that is characteristic for Homo sapiens.
This phase of early development is unique to modern humans, and absent from chimpanzees and Neandertals."
). Yet there we are.

In terms of overall shape analyses, morphometric analyses are particularly useful for analysing these kind of ideas - e.g. http://tinyurl.com/c3aqcsr - "Dispelling dog dogma: an investigation of heterochrony in dogs using 3D geometric morphometric analysis of skull shape : Geometric morphometric analysis reveals that the cranial shape of none of the modern breeds of dogs resembles the cranial shapes of adult or juvenile wolves.
In addition, investigations of regional heterochrony in the face and neurocranium also reject the hypothesis of heterochrony. Throughout wolf cranial development the position of the face and the neurocranium remain in the same plane. Dogs, however, have a de novo cranial flexion in which the palate is tilted dorsally in brachycephalic and mesaticephalic breeds or tilted ventrally in dolichocephalic and down-face breeds.
Dogs have evolved very rapidly into an incredibly morphologically diverse species with very little genetic variation. However, the genetic alterations to dog cranial development that have produced this vast range of phylogenetically novel skull shapes do not coincide with the expectations of the heterochronic model. Dogs are not paedomorphic wolves.
").

(Similary, Asians, Europeans, Africans are only limitedly understood, at best, as neotenised versions of one another, in any directions. Sapiens are not neotenised Erectus. &c.).

Sean said...

Europeans' face shape is feminized just like their skin colour. Read 'Second-to-fourth digit ratio and facial shape in boys—the lower the ratio the more robust the face."


Peter, could it be there was there was a normal amount of maternal feeling for agriculturists, but a mismatch between the maternal feeling and particularly abundant local resources available. That is, mothers had the resources avialable to let frailer children survive, but were acting too conservatively for local conditions. The Solomon Islands have extremely fertile land due to a favourable climate and volcanic soils. You now have the correct explainations for the existence of blonds in Europe and Papua New Guinea.

Anonymous said...

Europeans' face shape is feminized just like their skin colour. Read 'Second-to-fourth digit ratio and facial shape in boys—the lower the ratio the more robust the face."

In the linked paper:

Characteristics of the European face such as relative anterior displacement of nose and posterior displacement of cheek seem better understood as being more developed than the African face, better than being less masculinized.

Narrowness of midface and height of nose seems no better explained by feminisation than further development of an adult shape (adults have relatively taller, narrower longer noses and narrower faces than babies).

The similar overall centroid size of European and African faces seems to support neither greater adult development nor feminisation of the European face (more feminised faces should be smaller, while more adult faces should be larger).

Based on this, and the prolonged development of the European/Caucasoid face shown by the paper, as an explanation model (while women have earlier maturing faces than men), I would say that accelerated facial development in Europeans takes it.

Sean said...

Someone needs to bone up on digit ratios. And then ponder why masculine digit ratios predict a robust face. And why Europeans have such unmasculine digit ratios.

Anonymous said...

OK. How about this? - check out page 178 in this PDF - http://hera.ugr.es/doi/15009579.pdf.

I wonder what you make of the fact that the German digit ratios for men and women and closer to the low Zulu digit ratios (and closer to one another!) than they are to the high Polish and Spanish digit ratios. Or that Finnish 2D:4D is lower than Jamaican 2D:4D for men and the same for women.

Or put another way - inter ethnic differences in 2D:4D looks like so much vaporware.

Anonymous said...

Still, this paper may interest you -

http://rspb.royalsocietypublishing.org/content/272/1576/1995/F2.expansion.html - the effects of 2D:4D shift in males

http://rspb.royalsocietypublishing.org/content/272/1576/1995/F5.expansion.html - the effects of actual face shift in a male and female direction

Notice the difference between the two sets of shape morphs.

When we talk about feminization, it seems that there may be differences of effect based on ontological timing of sex hormones.

The effects of androgens prenatally, as measured by 2D:4D seems to accord more with your perceptions of 2D:4D - higher androgens = broader faces and a slightly shorter jaw.

Actual male:female sex differences which emerge from sex hormones and growth trajectories during life (and reflected real differences between men and women) are different - higher androgens and differences and more male growth trajectory = narrower faces with a compressed midface and much taller jaw.

Sean said...

Finns have broad robust faces (and darker skin than other N.Europeans), and they may have picked up quite a bit of Lapp ancestry since leaving the northern European plain. Has anyone ever said that Finnish women are the most beautiful in the world? No.

They say that about Danish women though, and the Danes have the lowest digit ratio in the world. And the lowest male fertility

Sean said...

Typo, meant to point out the fact that that Danes have the highest digit ratio in the world.

chris said...

With respect to the robustness of digit ratio theory.

http://www.epjournal.net/blog/2012/04/the-2d4d-ratio-a-new-paper-points-the-finger/

Anonymous said...

Finns have broad robust faces (and darker skin than other N.Europeans)

Finns seem to score as high on light eyes and hair as Danes and higher than say, English and Irish.

http://upload.wikimedia.org/wikipedia/commons/3/33/Westernparadigm_blue_eye_color_map.jpg

http://forums.skadi.net/photoplog/images/25637/1_blond_hair_map1.jpg

In any case, your contention is that feminisation was responsible for the shape changes in the European face from African, not heterochronic acceleration. You can't go and reduce your definition of the European face to "Danish" midstream.

...

They say that about Danish women though

People say that about Brazilians and even Thais and Japanese... I'm not too interested in that kind of speculation... Brigette Nielsen, Connie Nielsen and Helena Christensen seem the most famous Danish female celebrity exports (also not seeming particularly narrow faced or feminine).

...

Incidentally, another interesting figure from the paper I posted above :

http://rspb.royalsocietypublishing.org/content/272/1576/1995/F4.expansion.html

2d:4d variation within female faces.

Notice how unlike in men, the female faces don't seem to show any association with facial breadth with 2D:4D ratio. The low female 2D:4D face does have a male face shape with its short broad nose and large jaw, but isn't really wider across the whole face from forehead to chin and across zygomas, compared to the high 2D:4D female face. Interesting huh?

Aside from not being related to actual male-female dimorphism in a "broader = male" pattern, pure facial breadth as an indicator of prenatal testosteronisation in females also seems to be lacking.

....

http://www.epjournal.net/blog/2012/04/the-2d4d-ratio-a-new-paper-points-the-finger/

2D:4D does not seem to have much to do with adult hormone levels or repeat polymorphisms in the receptor genes, regardless of how it reflects experiences in utero.

Sean said...

"your contention is that feminisation was responsible for the shape changes in the European face from African, not heterochronic acceleration."

No, my contention is that the face shape of Europeans was driven by sexual selection for appearance so I'm arguing against natural selection, not the 'heterochronic acceleration' process. Nor am I arguing that cold adaptation is responsible for the high 2D:4D and delicate facial features of northern Europeans. Hence it does not follow from anything I say that that the northernmost Europeans (ie Finns ) should NOT have low 2D:4D and robust faces (and be genetically very untypical of northern Europeans, as they are).
Danes are far more typical of the mass of the population of Northern Europe. Europe has the highest 2D:4D, N.Europeans have 2D:4D that is high compared to other Europeans, Danes have the highest 2D:4D of all, the lowest fertility of all, and are up to four times more likely to have testicular cancer than the most untypical Europeans - the robust faced and low 2D:4 Finns (who have a very high murder rate).

You seem to accept that in Europeans jaw is less massive (and associated with higher digit ratios). OK what do you think the advantage of that was. Bear in mind that the crowded and impacted teeth that go with a small dental arch would have had resulted in all sorts of complications. The first exampla of an impacted wisdom tooth in a human was Madelenian Girl. But why did Europeans evolve that way, eh?

It seems to me you are agueing for natural selection for smaller faces in Europeans, but you can't say why these smaller faces were selected for. I think it was looks.

chris said...

"Danes are far more typical of the mass of the population of Northern Europe."

Northern Europe is a massive place. Denmark is a very small country in this massive place, therefore you can't just define them as being the most representative of Northern Europeans.

Northern Europe:
http://en.wikipedia.org/wiki/Northern_Europe

Denmark pop: 5.5 million
Sweden pop: 9.4 million
Norway pop: 5 million
Lithuania pop: 3.1 million
Latvia pop: 2.2 million
Estonia pop: 1.3 million
Iceland pop: 320 000.
Finland pop: 5.4 million.
Ireland pop: 4.5 million.
United Kingdom pop: 62.2 million.

Now you could refine your argument and say that the Danish are representative of Scandinavians.

http://en.wikipedia.org/wiki/Scandinavia

But even then, Denmark only constitutes about one quarter of the population of Scandinavia and so can hardly be said to be representative of all of it. If that title had to belong to just one Scandinavian country at all it would be Sweden, which if I recall correctly has a digit ratio for men of 0.95. (I remember this because I looked it up to see if the degree of feminism in a society had any sort of relationship to the digit ratio of that country's men.)

Ben10 said...

It was published yesterday. Non-white babies now officially outnumber white babies in the US.

It's not survival of the cutest, that I am sure. Main stream media praize the fact, needless to say.
What about Canada?

Sean said...

With the settled rates immigration we have now (of the 25.1 million employed in the UK, 4.1 million are foreign born) the white population will be a minority everywhere in two generations, and a tiny minority in 100 years. What is really going to change faster than anyone thinks possible is the genetic integration of Europeans with immigrant communities. Sexual selection will have a hand in it, on a number of levels; Denmark is the most liberal country in the world, and its women are far from unattractive.

Sean said...

anon, Look at Inuit if you want to know what people who are adapted for breathing cold air look like. They do not have long thin noses.

chris, Judging by the genetic data Finns are very untypical, hence they've surely altered, by admixture, during their wandering from the European plain to land that was under a kilometer of ice 9000 years ago.

Danes live on the Continental coast where they always have. DANES must be far more representative of the ancestral North European Plain population than Finns or Swedes. The Denmark land area itself is not huge, but its population expanded massively into Britain.

Anonymous said...

Sean:

My opinion on this is still that, given the 2D:4D ratio seems to vary between local populations without a difference in femininity

- e.g. Polish and Spanish are not particularly more feminine than English, despite their men having higher 2D:4D than English women and there AFAIK is no chasm in femininity between German vs English and Spanish and Polish women, all as shown by the paper I cited -

why should we be at all optimistic about using 2D:4D differences between populations, suddenly, as a predictor, when we are comparing Danes to Finns, or Europeans as a whole to Africans? If there is no or almost no predictive power in these closely related populations, there would probably be even less between less related populations.

Seems like vaporware.

.....

anon, Look at Inuit if you want to know what people who are adapted for breathing cold air look like. They do not have long thin noses.

I'll tell you what I know about Inuit nasal morphology:

Inuit/Eskimos and subarctic Native American have

a) a narrow nasal index - http://tinyurl.com/bq7q3jq and http://tinyurl.com/d6cqgtg, where the Eskimo sample has a narrower and more opposite the African typical nasal index than the European sample.

and

b) pinched nasalia - see http://95.211.45.61/hanihara.flatness.pdf where Table 6 shows Eskimos and subarctic populations having a European typical simotic index (closer to the European average than the Lapps and Finns are) just with the nasal bones scaled down in absolute size.

Also, Inuit substitute for a smaller external nose (or similar or more extremely "untropical" shape than Europeans) by increasing the volume of the internal nasal conchae :

Lieberman, 2011 - "Because the ancestors of modern European Americans evolved in cold, arid climates, they may have undergone selection to narrow the nose and hence increase the turbulence of inspired air so as to increase the nose’s ability to humidify and warm air on its way into the lungs. Another way to increase respiratory epithelium surface area is through expansion of the conchae within the nose. This probably explains why cold-adapted Inuit populations from the Artic have significantly larger intranasal volumes and surface areas than populations from warmer regions, but they don’t have bigger overall midfacial or maxillary sinus dimensions (Shea, 1977)"

I don't know the reasons why Caucasoids do this one way, while Arctic Mongoloids do it another way. It might be that shape factor in the proto-Caucasoid or proto-Mongoloid population made one method work better than the other..

But why would "feminisation" lead to a broader (lower nasal index) and larger and more projecting nose (higher absolute nasal bone size) in Europeans than arctic Mongoloids? Climatic selection combined with leeway/randomness in whether it is the external or internal nose that gets narrower and/or larger, that seems much more likely to explain differences in nasal shape.

Anonymous said...

"(Similary, Asians, Europeans, Africans are only limitedly understood, at best, as neotenised versions of one another, in any directions. Sapiens are not neotenised Erectus. &c.)."

"Seems like vaporware."

No. Ashley Montagu and others are mostly correct; the patterns are as clear as day, unless one selectively ignores the evidence.

Sub-Saharans -- Less developed brain structure (convolutions), with cranial morphology more similar to ancient primates. Lack of complex language and behaviour compared to other modern humans. More paedomorphic features than archaic types, but less neotony overall compared to other races.

Europoid -- More radical mutations than all other hominins, more complex brain function, more paedomorphic features than Africans. More delicate bones than Africans (or Neanderthal for that matter). Maturation rates closer to mongoloids.

Mongoloid -- Even less robust skeletal structure than Europoids, less body hair and sex hormones, lower two-egg twinning rate, slower maturation, larger crania, and more paedomorphic features than other hominin.

Look at the genetic distance studies and Fst values...

Sean said...

The nose getting longer and narrower is not exactly a complicated thing for natural selection to manage, yet we are told that for Inuit (who undoubtedly are cold adapted) the quick fix never happened. Finns and Saami have shorter and broader noses that North Europeans who live in lower and warmer latitudes. How then can you continue to maintain that the long narrow nose of N. Europeans is cold adapted? Finns have robust physiques and broad-jawed robust faces, their short broad noses are just a reflection of the fact that Finns are robust.

Anonymous said...

As to robust skeletal structures, is there a place for African pygmies and Bushmen in this schema? Or smaller statured South Asian compared to European populations?

I don't even see what "two egg twinning rates" have to do with neoteny, exactly. That sounds like a random Rushton factoid that has nothing to do with neoteny..

Anonymous said...

the patterns are as clear as day, unless one selectively ignores the evidence.

First, Mongoloids don't have slower maturation, physically than Caucasoids

http://highered.mcgraw-hill.com/sites/dl/free/0072414561/16698/ch01.pdf

http://books.google.co.uk/books?id=ZPeMjYy65_sC&lpg=PA161&ots=Hr3HWx8B3v&dq=eveleth%20maturation%20asian%20tanner%20stage&pg=PA157#v=onepage&q&f=false

East Asians have slightly retarded development until puberty, relative to Europeans, but begin menarche and puberty earlier and develop faster through every stage, including skeletally. Perhaps they lag psychologically, but this isn't the case, physically.

Africans are just more advanced at every age.

Facially, Mongoloids have some less neotenous facial features, such as their taller, vertically larger and broader faces and relatively small and narrow orbits (compared to Caucasoids and Negroids). As well as more neotenised features, such as the flat nose and relatively projecting cheekbone. They may be neotenous compared to Caucasoids overall, but it does not their craniofacial shape very well.

Obviously, Negroids are facially neotenous overall, compared to Caucasoids, as in the paper I have given a citation of above. What's your response to this?

In terms of body shape, I suppose you could understand Asian limb lengths as neotenous. But climatic selection seems a better explanation, that climate specifically selected for those limb lengths, given that we already have Bergman and Allen's rules, than that they a side effect of an overall neotenous growth pattern (as per Montagu/Gould).

As to robust skeletal structures, is there a place for African pygmies and Bushmen in this schema? Or smaller statured South Asian compared to European populations? Or Homo Floresiensis?

I don't even see what "two egg twinning rates" have to do with neoteny, exactly. That sounds like a random Rushton r:K factoid that has nothing to do with neoteny..

Overall, other than brain size, most of the other aspects of neoteny that Montagu proposes, such as

- decreased body hair in Mongoloids (but not increased baldness in Caucasoids or decreased body hair in Africans relative to Caucasoids)

- Mongoloid (and Negroid) relatively flatter noses and chins and the short stature of Mongoloids,

all either questionably relevant to human evolution (the kind of oscillations in body hair we see among H Sap are nothing large for two different clades of chimps) or do not show, across human evolution, a neotenous pattern of shift in the Mongoloid direction (flatter noses and chins with more projecting malars and short stature).

My contention, to be clear, was not that there are no heterochronic differences between human populations. Obviously that wouldn't make be consistent with the paper I originally cited. Nor that one population could not be more "neotenous" or "accelerated" than another in the "final analysis".Nor, even that Homo Sapiens was not more neotenised than accelerated, compared its ancestral hominins (although that I would say, is contentious).

It was that trying to understand the differences between racial groups and between hominid groups in terms purely of establishing a ranking of neoteny and as a neotenic trend is a piss poor framework, particularly in terms of understanding actual selective pressures.

And that rather than this, heterochrony, and not always in a neotenous direction and not globally applied but generally affecting organs locally, should simply be seen as one method of "tinkering" in an evolutionary process which also involved non-heterochronic change.

Sean said...

Lots of people live at the lattitude of Europe, but they do not have the face shape of Europeans. If European womens' distictive face shape were the result of cold adaptation and random 'drift', they would look a lot worse than they actually do.

Anonymous said...

The nose getting longer and narrower is not exactly a complicated thing for natural selection to manage, yet we are told that for Inuit (who undoubtedly are cold adapted) the quick fix never happened.

If you'd read what I wrote, you'd see that the Inuit have narrow noses as measured by nasal index.

Also, how do you know that a narrower external nose is a "quick fix" compared to increasing the size of and narrowing the nasal conchae, exactly? Which is how the Inuit have evolved. Particularly from what was likely an proto-Mongoloid baseline.

Finns and Saami have shorter and broader noses that North Europeans who live in lower and warmer latitudes.

Interestingly, narrow and projecting noses are common in populations from the arid regions of West Eurasia as well. Most of the physical anthropology literature on nasal index stresses narrow noses as an adaption to the cold and dry, not just the cold, after all. E.g. see my Lieberman quoute - "cold, arid climates"

The difference with Finns may reflect that Finns have population elements which have been resident in the relatively humid Northern European northwest European plain, while other "Northern Europeans" have received more Mediterranean and West Asian gene flow. That would seem compatible with present autosomal evidence (I know Peter is skeptical, as am I, nonetheless...).

Classical physical anthropology, after all says, http://www.theapricity.com/snpa/chapter-VIII4.htm - "The Palaeolithic survivors were not notably leptorrhine; they were, in fact, much less so than the Nordics and others who followed them."

Sean said...

"In a study of variations of the size of the maxillary sinus, Shea noted that maxillary sinus capacity decreases absolutely and directly in the Inuit with decreases of the average ambient temperature in which they live"

Classical physical anthropology would say reduced surface area is cold adaptation. Inuit noses do not look like like Max Von Sydow's (long and thin, with a greater surface area and easily frostbitten). Inuits' adaptations to breathing cold air do not include noses that are remotely similar to the nose of von Sydow. So why did natural selection skip this simple adaptation, if a Sydow nose is adaptive in cold temperatures?


If European face shape is not due to sexual selection why do European women look so good ?
I give up.

Anonymous said...

Increased surface area to volume ratio is what anthropology normally suggests as cold adaptation, not decreased surface area.

I'm not saying European/Caucasoids are more or exactly as adapted to the cold than are Inuit, I'm saying they're more adapted to cold than are Africans, and that the Inuit and European/Caucasoids are both adapted to colder climates in different ways.

Having said that http://en.wikipedia.org/wiki/Mongoloid - "Professor of anthropology at Trent University Ontario, Canada, Joseph K. So (Chinese: 蘇) (198) cited a study by J. T. Steegman (1965) that the "so-called" "cold-adapted Mongoloid face" has been shown in an experiment, using Japanese and European subjects, to not offer greater protection to frostbite."

Suggests that arctic Mongoloids may be more adapted to cold (or frostbite) than temperate Caucasoids and Mongoloids (of course, there are no arctic Caucasoids), who may not be better adapted to cold and frostbite than one another.

Anonymous said...

Found a reference for Steegman's experiments - http://tinyurl.com/dxcn7jc

"Dry cold stress, particularly frostbite stress, has been proposed as the selective force that led to the emergence of the Mongoloid face...

Protruding, thin features were thought to be more in danger of freezing...

Steegman (1972) tested this hypothesis in a laboratory using subjects of Asians and European descent, he found that the larger prominent malar bones of Asians got colder than the cheekbones of Europeans when subject to an air stream at 0c for 70 minutes...

Nose shape and prominence, furthermore, were unrelated to nasal temperature

The Mongoloid face then could not have been produced by selection through frostbite stress"

Sean said...

I see, so Anders Breivik's extremely broad face must be a coincidence. Like Jessica Alba's Danish mother and Scarlet Johanson's Danish father.

Anonymous said...

Non sequitors are always good when you can't be bothered to deal with the way an argument is going.

Well, Jessica Alba's mixed Danish/French Canadian mother is a looker, you've got me there -

http://crushable.com/files/2009/01/27282pcn_alba10.jpg
http://anythinghollywood.com/wp-content/2009/01/1_11_09_jessica_alba_0.jpg &
http://www1.pictures.fp.zimbio.com/Catherine+Alba+Jessica+Alba+Family+Spending+PqtJEUYw7Twl.jpg

Broad face or not broad face, what do you think?

Johanssen seems like she takes more after her Jewish mother than her Danish father, in the good looks department - http://4.bp.blogspot.com/-wb2d5hV5S8w/TWepvvfkluI/AAAAAAAAGVg/od1J-vpOBeA/s1600/karsten.jpg vs http://www.superiorpics.com/pictures/3C7V140558049.jpg- he seems like he has a typical, low, broad face to me.

What do you think about the old "facial index" maps like this one? http://www.theapricity.com/earlson/reeh/maps/mapix.jpg

Doesn't seem to indicate particularly narrow faces in Europeans (or Northern Europeans) compared to people around the Mediterranean. Or Danes particularly.

Anonymous said...

North Europeans expanded south-wards. Later Danes expanded into Britain where they expanded massively and made Britain great, the first modern state. Then Puritans (mainly from heavily Danish East Anglia) made the USA great. The N. Europeans are able to create such societies because they are less orientated toward male-male competition than other peoples. It is not surprising to me that, among popular actresses, Danish ancestry is disproportionately common. Erik's site reported a survey found British and Danish women are rated the most attractive. The Danes produce oddly feminine thought ie Keirkegaard (self negation), and they surrender after one air raid. No Dane stands comparison with the huge jawed Simo Häyhä.

Anders Breivik does have a very broad face.

Anonymous said...

Eskimos are heterogeneous, maybe surprisingly so, and it would be wise to look at the physical anthropological literature before assuming your mental picture's accurate. Are all of you aware, for instance, of how extremely dolichocephalic some eskimo populations are?

Anonymous said...

The N. Europeans are able to create such societies because they are less orientated toward male-male competition than other peoples.

Finnish society = train wreck of inter-male competition. Who knew?

And here was everyone thinking it was:

"Finland has recently ranked as one of the world's most peaceful, competitive and livable countries." - http://en.wikipedia.org/wiki/Finland

Shame they aren't like the English with their crime rates, renowned across Europe as low.

Anonymous said...

This post almost takes the cake for how flimsy and bizarre your theories of sexual selection can get. You acknowledge blonde hair is widespread across the pacific and is even found at high frequencies in central Australia, yet home in on Papua New Guinea, an extraordinarily diverse country who's inhabitants have been isolated for millenia, and tie in present rates of child neglect (in this large, diverse island) to possible selection for blonde hair, which you then extrapolate to all of Oceania. Therefore, this is good evidence blonde children are less likely to be neglected (atleast if they're dark skinned), and Papuans (or Oceanians as a whole) selected for this.

This gem also really brought out the neurosis in Sean, one of your creepy fanboys, to prattle on about how robust and ugly and brown the Finns are because they've been tainted by subhuman mongoloids, and their violent dispositions, giving Finns, as I've now learned, have a "very high murder rate." And some kind of Danish supremacist (who also laments the sort of feminine thought they can produce.) Perhaps the autistic, schizoid nordicist Erik Holland of femininebeauty.info (also known as J Richards of Majorityrights, and who I assume is being favorably cited as "Erik's site) and his prediliction for trailer trashed bimbos as the height of femininity can also be seen as another downside of Danish hyperfemininity.

Anonymous said...

You also seem to think it very remarkable that blonde hair is lightest in children in Oceania, when this is the case for just about every case of light hair in the world, despite initially acknowledging it for europeans. Maybe it's just that light hair alleles that are lost after childhood are the most common, since it's not only the case in europeans and australo-melanesians, but also in populations like hmong and native peruvians, who never retain them beyond childhood. But I'm sure you'll be able to find some far-fetched sexual selection/neoteny theory to explain even those.

Still really like how you extrapolate modern child neglect in Papua New Guinea to the rest of the entire region, which includes many highly isolated, widely dispersed islands. And for the record: http://blogs.discovermagazine.com/gnxp/2012/05/case-closed-blonde-melanesians-understood/

"The study was a classic cases vs. controls GWAS. They looked at variants in a lot of people with the trait, vs. those without the trait. Additionally, if you check the supplements and read the text it’s obvious there is no population straification. That is, having blonde hair is not correlated with a different ancestry in these Melanesian populations."

Child neglect everywhere, right?

Anonymous said...

"One possibility is child neglect. Papua New Guinea has a relatively high rate of child malnutrition—35% on average, with some regions having rates as high as 78%. Yet malnourished children are found in areas that have an apparent surplus of food. Lepowsky (1987, p. 75) notes that “the reported pattern of child malnutrition did not follow environmental or ecological patterns but cultural ones.” The ultimate cause seems to be “maternal detachment”:"

It would be helpful if you bothered to look up if these regions correlate with the frequency of blondism (or other light hair colors), but you don't, and it's doubtful they do, since light hair isn't terribly common even in papua new guinea from what I've seen. Other islands in Oceania have much higher rates, but it's a tad unlikely they also have such high rates of child neglect.

Anonymous said...

"In equatorial Oceania, the evolutionary path may have been both similar and different. As in Europe, there is an aesthetic preference for blond hair:"

I'm sorry, but isn't this just about Samoans? Aren't they a polynesian people? What do they have to do with papua new guinea, which is nearly 5,700 km from Samoa? Did it ever occur to you that most New Guineans don't have blonde hair (or any light hair for that matter) and that it isn't widespread throughout Oceania? I had no idea Samoans could exhibit light hair, but that quote is clearly about a reddish color and not blonde. It seems to be quite uncommon in Samoans, and Samoans are not that dark- how do you think this was selected for to some substantial degree?

Others have ripped into this post like crazy, yet you're silent after all this time. I was googling around for information on blonde hair in new guineans and I bet that's how the others arrived too on this obscure, pseudoscientific blog. I can't get over how utterly retarded this post is and even creepy, especially with that picture and header- yeah, that little boy's blonde hair is just a marker that cries out so his hideous black skin can be overlooked, right?

I'd be careful trying to get this published, people might end up thinking you're autistic or even sociopathic.