Ben says:
Variation exists in all populations; there is no individual trait exclusive to one region. But previously you suggested that dark-skin was not Egyptian.
You certainly drew an "exclusive" barrier than excluded numerous people.
Indeed, the fact AA's fall between Europeans and tropical Africans just confirms the extent of their European mixture. Completely wrong and shows you do not understand the data. The position of
African-Americans have nothing to do with any "race mix." It has to
do with their deeply embedded ancestral tropical adaptations which are
slow to change. Other African populations like Egyptians show the same
adaptation pattern. That is why they cluster closer together, not because
of any "race mix." The continuum is based on climatic adaptations reflected
genetically, not whether anybody "mixed." This fact is also proven by
NON-African tropical populations with little race mix, such as Melanesians.
They also show cluster with other tropicals and away from Europeans.
Egyptians cluster with other tropical Africans like themselves, first with
those geographically closer in Nubia and the Sudan, but even with other
tropically adapted African descendants thousands of miles distant in America.
African American admixture by the way is nothing earth-shattering- between 6 and 25%
depending on the study looked at (Parra 1998, Norton and Kittles 2005 etc)
White Americans can show up to 20-30% African ancestry depending on the sample used.
But this makes little difference, for limb proportions change so slowly that
admixture has relatively little short-term impact.
Beals' data which you criticize was independently verified by Hiernaux (1968) for Sub-Saharan Africa and Crognier (1981) for Europe. I criticized HOW you were using Beals data in your argument, what
Beals shows, as I note above is the effect of temperature. But temperature
is merely ONE variable among others, and brachcheplization is a quite plastic
feature, affected by better resource access and living standards, and other
things, including cultural practices. So sure Beals got some temperature correlations.
That is hardly enough to make your argument strong, especially given the highest
diversity of indigenous Africans, and given people moving around.
Instead, as I noted mesocephaly is more prevalent (up to 40%), which is expected since Egypt is at sub tropical latitude. Ancient Egypt had a much greater frequency of mesocephaly than southern (tropical) zones .But as already shown in detail by credible scholars head shape is
dependent on more than mere temperature. Furthermore people are
not static in the Nile Valley but moved around for millennia, adapting
to varying conditions. Head shape can vary significantly within a
generation, it is quite plastic, unlike limb proportions. The greater
frequency doesn't mean much in terms of your argument.
Based on the available data, I fail to see how the ancient egyptians can be considered tropical when most (excluding south Upper Egyptians) were lighter brown in colour with high proportion of rounder (i.e. low mesocephalic) heads. Actually based on available data it is hard to see why they should
NOT be considered tropical, and hard to see why "light brown color"
excludes them from being that. Africa has the highest skin color
diversity in the world. Light skin is noting unusual - its BUILT INTO
Africans. Climate is not the sole cause of lighter skin in Africa.
Its BUILT in genetically. Rounder heads are also nothing special-
they are well within the ultra diverse African range, and are quite plastic-
affected by numerous enviro factors.
Most skin color diversity – Quote:"Regional differences in local within-population [skin color]
diversity were examined using two measures of variability: the
sample variance and the sample coefficient of variation. For both
measures, the average level of within-population diversity is
higher in sub-Saharan Africa than in other geographic regions.
This difference persists even after adjusting for a correlation
between within-population diversity and distance from the equator.
Though affected by natural selection, skin color variation shows the
same pattern of higher African diversity as found with other traits." -- Relethford JH.(2000). Human skin color diversity is highest in
sub-Saharan African populations. Hum Biol. 72(5):773-80.)
And in social construct terms, "negro" or "black" includes
people with brown skin, or light brown skin.
The coefficient correlation is 0.60 (Beals, Crognier). It is obviously fairly strong, but not great. .
As already noted, temperature is merely one variable. Beals' study
is hardly an earth-shaking measure Her sample showed that angle, others
show other variables. And people moving around the Nile Valley for
millennia would be affected by various temperatures- so temperature doesn't
make the case. A tropical African could move in and out at will, and show
show skull changes within a generation due to more food production.
The fact that the ancient Egyptians show SUPER tropical proportions after
all those millennia, or "super-negroid" proportions to use Robins and Shutes
old terminology, shows that they most definitely are a tropically adapted people,
a marker that is slow to change, unlike highly plastic head shape.