That is true - in terms of the original thread, though dealing with Ignatiev is a different matter, even though the main thrust here is upon the mixture characterizing modern (including Western) civilization. In the old days local geographic isolation was much greater - the Pygmies of central Africa exhibit this most clearly. The Bantu migration around the Congo from West to East then Southern Africa linked up otherwise relatively isolated hunter-gatherers because the Bantu were pastoralists dependent upon cattle, the migrations occurring roughly around 500AD. The Bantu peoples look different to the Khoisan people of Southern Africa (i.e. the !Kung Bushmen today and the original Strandloopers and Hottentots); indeed most black South African tribes e.g. the Xhosa, are a mixture of Bantu and Khoisan people - hence the odd spelling of the word 'Xhosa' which is pronounced with the implosive click language of the Khoisan peoples. The Sahara Desert also isolates most North Africans from equatorial peoples and even from Egypt! The ancient Egyptians felt closer to Nubians than to Libyans (Caucasian North Africans) or Middle Eastern (Semitic) peoples, as Champollion understood.Jerry Russell said:In some cases of highly isolated indigenous populations, there might very well be enough geographical separation to prevent any gene flow. These highly isolated populations could arguably represent distinct subspecies or races. However, the description of clinal variations is accurate for Africa and the Eurasian continent, where there is little if any local geographic isolation . The indigenous have been under massive attack from Eurasian-based civilization, their numbers have been decimated, and interbreeding is extensive.
And I don't think you're interested in talking about indigenous peoples, anyhow. In our context, this is a red herring.
Concerning 'subspecies' the term is NOT strictly defined genetically.
Wikipedia is a source written by popular authorities, not genetic experts who have to restrict their technical jargon in order to prevent horrific ambiguities.Jerry Russell said:I don't know where you get this idea. Or, can you give a reference? Wikipedia definitely contradicts you, and so does everything else I can find on the web. 'Subspecies' and 'Race' are synonymous, although the latter term is deprecated. Lions and tigers are separate species, just as donkeys and horses are separate species, even though both pairs can readily hybridize. Ligers and mules have drastically reduced fertility compared to lions, tigers, donkeys or horses, but back crosses have been demonstrated.
In the case of mules the back-breeding engenders essentially pure donkey offspring. I don't know about the 'liger' fertility and perhaps there is no clear evidence yet, given the need for funding to support a liger population for breeding - another question here being "what is the use of them other than for gene research?" If ligers can mate successfully and produce offspring with a mixed gene pool then I would class lions and tigers as subspecies. Not so with humans who are all interfertile with success, hence I would not use the term 'subspecies' for human geographical variants.
Note that there are rock wallabies (Petrogale persephone) in Australia, lumped under one species, that cannot interbreed successfully between subpopulations since they have accumulated too many mutations over the millions of years - despite mating successfully in that they are morphologically indistinguishable. Hence the one species is actually separate species, originally developing from geographic variants of a once widespread single species. That is, the gradual emergence of species requires mutations over time - with geographic variants then subspecies and finally species - with a restriction of interbreeding. I.e. species will emerge even without Darwinian natural selection due to the continous generation of mutations, reproductive isolation (i.e. the separation of rocky habitats suitable for the wallabies) and accidental replacement of an original gene variant by a mutant.
I only emphasize these points in order to illustrate dialectical thinking - the excluded middle in logic. Formal logic, traditionally privileged by the West against Hegel, now combats dialectical logic by seizing upon human intermediate-appearing clines (the excluded middle) as the components of a new formal logic, this formal logic excluding any geographical genetic difference between people since the extremes of human appearance can no longer be addressed because they have been obliterated by the formal logic. The formal logician (e.g. followers of Ignatiev) will then brand 'racist' anyone who brings up the subject e.g. someone noting the social fact that most people in the USA privileged by wealth are disproportionately White.
You are correct in that genetic segregation has largely disappeared due to increased human travel opportunities, but the 'tiny isolated indigenous populations' left are an artifact of colonization and human technology over the last 3-4,000 years.Jerry Russell said:There is human geographical variation, but no "genetic segregation" aside from the tiny, isolated indigenous populations you mentioned. We agree, however, that human geographical variation does exist.
A platypus might look like that but the 'bill' is fleshy not hard like a bird's. It has fur; it is an egg-laying mammal, a monotreme like the echidnas and had an extinct relative in Argentina (Monotrematum). Given McCarthy's statement to the contrary I find it hard to believe that he is a genuine scientist. Now I don't deny that interspecies combination could occur, but if so that would to human genetic interference e.g. combining chromsomes of different species together to see if viable offspring cells could be produced in a test tube. Getting these cells to grow into viable adult organisms is quite another question however, something we are still trying to solve.Jerry Russell said:All I can say is that McCarthy has carefully considered this issue, and doesn't believe it's a problem.
You say his examples of hupigs and such are mutants, he says they're the result of bestial encounters. McCarthy's PhD seems to be as good as anyone else's, and nobody is claiming to have done the necessary genetic analysis. So it seems that only Mother knows for sure, or maybe she doesn't know either.
McCarthy says there is indeed genetic evidence that the platypus is a bird-mammal hybrid, which is exactly what it looks like.