Posted: Aug 18, 2011 8:47 pm
Galaxian wrote:It shows clearly that there is no such thing as a 'mosaic' structure to humanity. The subsaharan African branch has been seperated from the European, Chinese, & Papuan branches for well over 100,000 years.
No, you just ignore what your opponents said.
You’re human family tree is oversimplified because its goal it to be focalised on the past mixing between Neanderthal, Denisova Man and non-africans populations. But as I said before with references there were far mor recent mixing between African and Non-African populations.
African and Non-African Populations Intermixed Well After Migration out of Africa 60,000 Years Ago, Genome Studies Show
Inference of human population history from individual whole-genome sequences
And do you remember th Haplogroup T estimed between 19,000-34,000 Before Present?
Well again human diversity is a mosaic whether you admit it or not.
So in fact you’re human family tree (such the others) ignores a lot of mixtures between African and Non-African populations. In fact I already explained those things in one of my previous post but naturally you’ve just ignored it.
Tiel wrote:I’m always amused by the attempts of «racial classification» of the various human populations. So what are the Caucasians? Are the Arabs Caucasians? If not are all the Spanish, southern Italians still Caucasians? If yes are the Indians Caucasians? And the Basque people are they also a race? Oh yeah you can define “sub-races” or more funny “sub-subspecies”. But according to some “phylogenetic/haplogroups markers” and the hierarchical model should we not define two, three or more races in African population and considers all the non-African populations as sub-races? And what about the fact that we have different phylogenetic markers so different ancestries within these “races”, “sub-races” or whatever?
As far I Know all racial classification simply give us a lame picture of the human diversity and recent evolutionary history!
Here I used google to translate from french a excerpt of a very nice summary of the problems posed by racial classifications
A) Simplified tree of human populations, as a classic by clades. This tree is the synthesis of a genetic analysis of 120 polymorphic alleles among 42 populations. It presents the kinship / proximity between populations. (L. Cavalli-Sforza and A. Piazza, 1988). This tree is not false, it is scientifically correct as it represents the relationship and average distances it is asked to represent the criteria considered.
B) Based on the same tree were added (in red) part crudely sketched major exchanges of migrants between populations. More complete, this tree fills the gap in the graph A tree, that it is no longer a simple splitting of populations, valid to represent the relationships between taxa with reproductive barrier accomplished but little demonstration of the complexity of the genealogy human population - all the result of interbreeding and ongoing dialogue.
C) Always the same tree, but even more complete and sophisticated: we superimpose other interpopulation interbreeding and gene flow.
A) Simplified Migration / diversification of human populations.
B) and C). Here have been added, with spots of different colors, resulting in recombination / redistribution mean alleles / individuals respond to these population movements (flows, migration, separation, recombination, etc.). Colors mean giving more pronounced at the extremes - continuous flow going in different directions - which of course was very roughly illustrated.
Each small group of points in this graph can represent a family, a tribe, or an individual with its genetic pool. (A) to (C), are graphs showing the broad strokes of history and the situation of humanity (C) Aggregate number, from their past (A) at a time and location given.
D) From this diagram, starts the racialization of aggregates, ie the mental transformation of humanity and its people in combinations and ordered groups, with their share of artificial and arbitrary. From the diagram D, the scientific study of the phylogeographic is transformed and alienated.
E) The groups here are even more shoddy, and F). We just superimposed idealized racial types (color) and even more crudely symbolized (B / W) according to the 3-5 old traditional divisions. These groupings are races - at least we try to illustrate graphically here - a poor design, a contradiction, and a handicap to understand the history of our species and its present diversity.
A note in this graphic approach: for its manufacture using software for image processing fairly simple patterns D, E, and F were reconstituted by texturing a mosaic in which the pixel values are calculated and assembled into tiles average value. We realize here the extraordinary similarity between the way the software calculates the average of different colors of an image area into a flat pad with a single average color, and how humans are mentally with groups from artificial and arbitrary to individuals and / or small population aggregates (set of alleles / individuals and small populations / aggregates), to assign these individuals to a larger group. Photoshop then assigns the pixels of different colors in a color block averaged (D and E), and our brain is about the same, inviting us to forget the reality (A to C) of what is happening in this appearance " Racial "the ends of a continuous variation biogeographic transformed into idealized races or racial divisions.
Galaxian wrote:Speciation is a law of Nature. I mentioned before that [b]even if we seed an empty world with a totally homogenous population of absolutely identical clones, & we have perfect travel & communication between them. So long as there is no medical intervention, & forced eugenics programs, & forced social control; the population will fragment into different cultures & phenotypes & subspecies, then species. And that is with the above perfect scenario.
And so mixtures is a law of nature just as Speciation and in fact there’s were a lot of mixture in the history of human populations.
And historically there were much forced social control to prohibit some unions and impose segregation and so go against what you have logically to call a “law of Nature”.
But perhaps will you say that these people are the result of the violation of the “law of Nature”?
I don’t think so!
