Talk:Race debate/Archive 1

message: "Scientific support for the Caucasoid, Negroid, Mongoloid terminology of racial classification has diminished over the past century. These terms originally denoted skull types and sprang from the technique known as craniofacial anthropometry, but these disciplines have been abandoned by the mainstream scientific community. Today...they are used in forensic anthropology as an indicator of ethnicity of skeletal remains." So the terms were abandoned, because craniofacial anthropometry was abandoned as irrelevant, but people can be classified into these types on the basis of anthropometry? Welcome in the mental house! Centrum99 82.100.61.114 14:52, 5 November 2007 (UTC)
thread_title: Misleading (or rather demogogic) statements in the article

message: The oldest separation of modern humans (according to Y-chromozomes and mtDNA) occured more than 100 000 years ago, and as the branching suggests, it very probably happened not in East Africa, but in south Africa. The group that headed north is classified as "haplogroup BR" by modern geneticists. The groups that stayed in south Africa were characterized by deeply branched Y-haplogroup A and mtDNA haplogroup L0. During the Middle Paleolithic, they further separated into two distinct branches: while Y-haplogroup A3b2 + mtDNA haplogroups L0a/L0f headed north, all remaining A-lineages and mtDNA haplogroups L0d/L0k remained in south Africa.
The group with A+L0d/L0k lineages that stayed in south Africa developed into today's Khoisans. They are subtle people (150-160 cm) with body proportions similar to that of Europeans (trunk index ca. 52%), yellowish skin, "peppercorn" hair and the presence of epicanthus, among other things. During the last millenium, they were significantly influenced by Bantus from the paternal side and from this mixture, a taller subgroup (Khoi/Hottentots) came into being. The presence of "clicks" in Khoisan language supports the idea that these sounds were present in the oldest human "Ur-sprache".
The group that headed north sometimes around 50 000 years BP and bore A3B2+L0a/L0f developed in the dry savannah of south-east Sahara. Today we know them as Nilotes, representatives of the most extreme adaptation to hot, dry climate on Earth (matched only by some Australian tribes). Their trunk index 48% betrays extremely long limbs that dissipate heat more efficiently, their skin is extremely dark, skull is long and narrow (again an adaptation reducing the influence of sun heat). Among pastoral Nilotic tribes we can find the tallest people in the world, whose average height exceeds 180 cm. On the other hand, some agricultural tribes are rather small, 170-175 cm. This is explained as a consequence of the specific diet of pastoral tribes containing lots of milk and heance a lot of calcium.
The people bearing Y-haplogroup BR headed to East Africa. Here they further diverged into two basic lineages marked by Y-haplogroups B and CR. It would be interesting to find out, if this divergence has anything to do with the explosion of Mt. Toba on Sumatra 71-73 500 years ago that was followed by an extremely dry and cold phase. It is possible that bearers of Y-haplogroup B were pushed to the forests in West-Central Africa by the extreme drought, because these rainy and wet places aren't just of the most pleasant ones. This is, after all, clear from the influence that this climate had on their phenotype: Today we know them as small Pygmies, only 145-160 cm tall humans with dark skin, long arms and relatively short legs (trunk index 52-53%), with highly mobile muscle morphology suited for fast movement in the jungle. Besides Y-haplogroup B, they also bear typical mtDNA haplogroups L1 and L2. However, it is interesting to note that the same haplogroups are present in Tanzanian Hadzabe, who were traditionally grouped with Khoisan on the basis of the presence of clicks in their language. Yet the Hadzabe obviously have nothing in common with Khoisan genetically, so this is another evidence that "clicks" were present in the original language of humans.
The branch CR probably stayed in East Africa until the end of the cold phase 60 000 years ago. It is logical to assume that the first migration out of Africa occured just at this time, when the climate on the Northern hemisphere mildened. These humans bearing Y-haplogroup C and mtDNA haplogroup M (a subbranch of L3) crossed the Bab al Mandab strait to Arabia and then followed the South Asian coast to India. They probably weren't capable to compete with Neanderthals in the Near and Middle East yet. The "C-clan" (also called the "Coastal Clan") diverged into several geographically differentiated "sub-clans": C5 in India (Veddids), C3 in East Asia/Siberia (Mongoloids), C4 in Australia (Aborigines), C2 in South-East Asia (negritos, Papuans, Melanesians). Hence, from the genetic point of view, they represent the ancestors of modern Mongoloids and dark groups traditionally classified into the Australoid race (Veddas, negritos, Papuans, Australian aborigines).
About 50 000 years ago, when more sophisticated Upper Paleolithic technologies appear in the Horn of Africa, another group from the branch CR decided to leave Africa and conquer Eurasia. These people were the ancestors of modern Caucasians (Europoids) and bore Y-haplogroup F and mtDNA haplogroup N. Although the first traces of Upper Paleolithic technologies were found in the Levant 47 000 years ago and certainly belong to this "F-clan", the branching of its lineages suggests that the first migration center was somewhere in the Middle East, perhaps in Iran, and the Levantine population is only a result of a secondary migration. After all, the mtDNA lineages coming from N in the Near East originate virtually only from one subbranch of N (R). About 45 000 years ago, during a warm interstadial, the people of the "F-clan" massively expanded from South-West Asia to Central Asia, Europe, North Africa and even East and South-East Asia, where they mixed with local populations of the "Coastal Clan" and created intermediate groups (Polynesians, American Indians, Papuan highlanders, partly even some mongoloid groups). These Proto-Caucasoids were obviously more capable than their Proto-Australoid predecessors and they successfully competed with the Neanderthals - until they completely eradicated them from the planet Earth.
What about the CR-people that stayed in Africa? Well, their fate was very intersting. About 45 000 years ago, when the Saharan plateuau was green and full of lakes, they expanded from the Horn of Africa northwards and westwards. At this time, their L3 maternal lineages were accompanied by a dominant Y-haplogroup E that prevailed after the Proto-Caucasoid's departure. However, about 25 000 years BP, during the advance of the new Ice Age, these people were virtually torn apart by the dissicating Sahara: clans marked by Y-haplogroups E1 and E2 headed to North-West Africa, clan E3a to the lowlands of West Africa, and clan E3b radiated between the Horn of Africa, the Nile Valley and North-West Africa. The bearers of E3a soon came into contact with forest Pygmies and mixed with their women (about 75% West African mtDNA lineages are of Pygmy origin). From this mixture today's "Negroids" (traditionally understood African blacks) speaking Niger-Congo languages, came into being. As the Bantus they later further expanded southwards and largely absorbed their archaic relatives (Pygmies, Khoisan). People from the clan E3b in the Horn of Africa (belonging to its subbranch E3b1) probably bore Afro-Asiatic languages and spreaded them northwards after the end of the Ice Age 8000 BC. Another subbranch E3b2 was already present in North-West Africa, where a mixture of these Sub-Saharans and Caucasoids created modern Berbers. It is very interesting to note that the "purest" descendants of the clan E in Africa are Somalis - they posess 78% E3b1 and 70% L3, by far the highest percentages of these "CR-clan"-lineages documented in Sub-Saharan Africa. This also has far-reaching consequences for the anthropology of Sub-Saharan Africa, because it means that the "Caucasoid profile" of Somalis is a local development and Somalis thus make up a distinct racial group. By the way, it also indirectly indicates that some incipient features of Caucasoid race may have been already present in East Africa 50 000 years ago. The current anthropological picture of the Upper Paleolithic is still very foggy, however, and there doesn't exist much support for this claim. I should also add that Somalis received a certain supply of (Proto-)Caucasoid genes in the Upper Paleolithic (10-15% K2 and pre-HV).
From this description it is clear that the traditional anthropological classification needs a fundamental revision. Only in Sub-Saharan Africa we can find four distinct phenotypes with very deep roots that could be classified as separated racial groups (Khoisan, Nilotes, Pygmies, Somalis). Besides another two mixed racial groups emerge there (West Africans/Bantus, Ethiopids). The non-African human groups make up two basic lineages: the Caucasoid and the Australoid/Mongoloid one. Further, there exist their mixtures (that are predominantly Australoid/Mongoloid in origin): American Indians, Polynesians, many Papuan tribes, Indian outcaste groups, partly even Mongoloids from South-East Asia and Australian Aborigines.   —Preceding unsigned comment added by 82.100.61.114 (talk) 15:13, 6 November 2007 (UTC)
thread_title: A key piece of information: How human races actually came into being

message: But we shouldn't forget that the degree of genetic diversity may not be identical with the degree of phenotypic diversity. I could list many good examples of distinct "species", e.g. South American fishes Loricariidae that are so similar that they can't be distinguished without the knowledge of their origin. Since many laymen have no idea, how large the human phenotypic differences are, I would list several extreme examples to illustrate it.
First, if we take height into consideration, the smallest average height can be found in the Mbuti Pygmies from Zaire (145 cm). The tallest human (sub)group in the world are European Caucasians and pastoral Nilotes with 180+ cm. More specifically, the tallest of the tallest are the inhabitants of the Dinaric Alps with 186 cm. This is a difference of 41 cm or 28%, which is roughly 6 standard deviations of a normal European sample. 
As for weight, we can again compare the lightest ones (small Pygmies with 45 kg) to the most robust human population in the world, Pacific Islanders (~90-100 kg at 173-179 cm). This is practically 100% difference in weight. 
And we can list even another important factor - limb proportions that are tightly bound with adaptations to climate. As for trunk index (the ratio between trunk length/body height), we can find heat-adapted extremes like African Nilotes and Australian Aborigines with trunk index roughly 48%, and cold-adapted extremes like Siberian Mongoloids, the Ainu and especially Patagonians with trunk index 54% or even higher. If we take a hypothetical average Nilote with 175 cm height and a hypothetical average Patagonian of the same height, the Patagonian will have 10.5 cm shorter legs than the Nilote. This may equal roughly to 6 standard deviations of the Nilotic population. Obviously, we could hardly find a Nilotic man with the average Patagonian value. In fact, their Gaussian bell curves hardly touch at all. 
From memory, I can also list differences in body width, which is again a factor resulting from climatic adaptation. According to "Dupertuis structural profile" (that can be found in the internet), an average Japanese male (i.e. a cold-adapted Mongoloid) matched for height has bitrochanteric width (i.e. hip width) roughly 103% of the average European value. On the other hand, an average youngster from the Ivory Coast has only 93% of the European value. This body width may be typical for all linear African populations.
I hope this will help those, who are looking for information of this sort. Unfortunately, I expect that I will have to regularly revert this text due to repeated sabotages of Mr. Leftie, who created this page. Centrum99 82.100.61.114 01:55, 6 November 2007 (UTC)
thread_title: Extreme examples of human phenotypic diversity