On “Primitive” Humans, Ancient and Modern (part 2: Ancient and Modern)
…I have seen nothing, which more completely astonished me, than the first sight of a Savage; It was a naked Fuegian, his long hair blowing about, his face besmeared with paint. There is in their countenances, an expression, which I believe to those who have not seen it, must be inconceivably wild. Standing on a rock he uttered tones & made gesticulations than which, the cries of domestic animals are far more intelligible. —Charles Darwin
At this point in the discussion, continued from last time, I would like to give a brief, theoretical sketch of very early human migrations out of Africa and within it, in the context of human evolution. But before that I should briefly address an increasingly popular idea, especially among amateur anthropologists, namely the “completely out of Africa” theory, which states that we didn’t arise in Africa at all, but rather did so somewhere on the Eurasian supercontinent.
The most recent upsurge of this idea took place a few months ago with articles on how an early human ancestor was found in Europe. This amounted to a few teeth and bone fragments of an apelike animal which might be a human ancestor unearthed in Eastern Europe. But this evidence, along with previous evidence supporting a non-African origin for modern humans, still seems to me to be less persuasive than a much larger collection of evidence in favor of the Out of Africa theory. So, until I see enough contrary evidence to be persuaded, I’ll give the standard, more or less orthodox account of human origins and migrations. I’m not sure why so many people have an antipathy for the idea of African origins, but we all have our reasons. At any rate, I’m pretty sure that the idea of the genus Homo, at least, arising in eastern Africa is not particularly controversial, except among people who reject evolutionary theory altogether.
So, according to orthodox theory, or at least one of them, concerning our biological origins, the genus Homo arose somewhere in the general vicinity of what is now Kenya maybe three or four million years ago. By two million years ago Homo erectus had already arisen, again in eastern Africa, with some populations migrating out of that continent into Eurasia. From western Asia H. erectus moved throughout much of the warmer areas of Europe and Asia—at some point they learned to use fire, but apparently hadn’t invented clothing yet, so they were mostly limited to the warmer regions.
By 500,000 years ago a population of Homo erectus had evolved into the more derived or “advanced” Homo heidelbergensis, after which some of them also migrated out of Africa and into Eurasia. A population of those remaining in Africa, somewhere in the northern half of the continent, eventually evolved into what is now called Homo sapiens, that is, anatomically modern humans, around 300,000 years ago. Also, some migrant H. heidelbergensis in the vicinity of western or central Asia evolved divergently into Neanderthals and a similar group, the Denisovans. This latter group mainly established itself in eastern Asia, with the Neanderthals living pretty much everywhere else, at least in scattered populations.
Here I may as well put in my own two cents’ worth and point out, as I did in an earlier post, that calling Neanderthals and Denisovans “pre-human” or a different species from us is ridiculous, considering that they apparently interbred with Homo sapiens and produced viable offspring. Almost everyone in the world, aside from sub-Saharan Africans, has Neanderthal DNA in their cell nuclei, and Austronesians and Australian aborigines in particular may have as much as 7% Denisovan ancestry. Furthermore, it has been determined that Europeans and East Asians are actually more similar genetically to Neanderthals than we are to black Africans—despite the absurd classification of Neanderthals as a separate species from us (and politically correct claims that blacks aren’t even a distinct race). Probably even Homo erectus could have interbred with us; and at any rate the cutoff between these archaic groups is arbitrary, as the evolutionary process was gradual, with rough, blurry transitions between one “species” and the next. But back to the orthodox story.
It is hypothesized, based on fossil evidence, that the first wave of Homo sapiens out of Africa occurred more than 100,000 years ago, but that some disaster wiped out all of them, or almost all of them, so that we apparently have no genes or traits inherited directly from them. A plausible theory cites the so-called Toba catastrophe, in which a supervolcano in Sumatra cataclysmically erupted around 75,000 years ago, causing a several-year-long “global volcanic winter” and a global thousand-year-long cold period, drastically disrupting climate patterns and of course stone age living conditions. It is estimated that fewer than 15,000 H. sapiens in total, possibly fewer than 3000, survived this near-extinction-event disaster, all or almost all of them in Africa.
The next wave of emigration from Africa occurred around 70,000 years ago, a group ancestral to Australian aborigines and also closely related to modern Khoisan “Capoid” peoples of southern Africa. (The Capoids, incidentally, are said to have diverged from the branch of H. sapiens containing modern Europeans’ ancestors soon after the advent of sapiens, more than 250,000 years ago.) This group evidently migrated eastwards along the coasts of tropical Asia, crossing the Indian subcontinent into Southeast Asia and then further southwards, eventually reaching Australia. As was already mentioned, this group interbred with the Neanderthal-like Denisovans. They presumably outcompeted the Denisovans that they didn’t interbreed with, and became the dominant “ethnicity” throughout southern Asia. Australoid groups are found not only in Australia and thereabouts today, but also in India, Sri Lanka (the Veddah), and in populations on the mainland of SE Asia. (Many SE Asians exhibit fairly obvious Australoid traits, such as dark skin, prognathous jaws, prominent brow ridge, and wavy black hair that turns brown in the sun.) Thus the Australoid peoples, according to the theory, represent the descendants of the earliest, most archaic human race to leave Africa and survive. This archaic status accounts for some traits which are quite politically incorrect to acknowledge, and which will be touched upon in due course.
The next major wave of migration out of Africa was the big one as far as we are concerned, as it includes most of our own ancestors. By about 45,000 years ago another group of H. sapiens began spreading from northeastern Africa throughout the Eurasian supercontinent. In Europe they became known as Cro-Magnon man. They apparently interbred with Neanderthals even before reaching Europe, and eventually outcompeted the latter everywhere they interacted, probably with quite a lot of typically human intertribal warfare.
Why did Cro-Magnon man, and H. sapiens in general, outcompete the Neanderthals who were already there, who were presumably better adapted to the new environment in most respects, who were certainly more familiar with their own territory, and who were not only physically stronger but had larger brains than the new intruders? The most widely accepted hypothesis, as far as I have seen, is that in Africa our Homo sapiens ancestors underwent a strange kind of mutation, resulting in asymmetrical brain function, or asymmetry to a greater degree, particularly with regard to the functioning of the brain’s cortex. Most western people probably have heard of the division of labor between the left and right hemispheres of the brain; well, that may be an innovation of our species, not found in archaic humans like Neanderthals, or else our species simply improved upon it. If so, it allowed us greater efficiency in some of our brain functions, allowing for greater skill in language and thus in symbolic thought, and thus, despite the Neanderthals’ larger brain, making us more intelligent, at least with regard to planning out survival strategies. For us humans, including our pre-human ancestors, survival has been predominantly a matter of intelligence, and every little bit has helped. We are physically slow and relatively weak, and lack horns and fangs, but we are smart—plus, when occasion arises, mean as hell.
This new wave of H. sapiens was more competitive than the members of the previous, Australoid wave also, and it outcompeted them pretty much everywhere they came into contact, so that Australoid tribes were restricted to remote areas like Australia and mountainous jungles. This later migrant group was more derived, judging from anatomical comparisons of, say, East Asians with Australian aborigines. Also, I have read that the Australian aborigines are one of the few ethnicities that enjoy a lower average IQ even than sub-Saharan black Africans—tending to score in the low to mid 60s, whereas African blacks tend more toward the low 70s. I have been informed that the only ethnicity or race which scores lower on intelligence tests than native Australians is the Khoisan bushmen of the Kalahari desert, with an estimated IQ of around 60 (plus maybe Pygmies). Again, intelligence is our primary asset for survival, and even small discrepancies prove significant, and decisive, when it comes to survival of the fittest.
The notion that people of the later wave were for some reason more evolutionarily derived and more intelligent than those of the earlier one helps to account for the fact that, in worldwide IQ testing, IQ goes down the farther south one travels into Asia, especially into Indonesia and Oceania—that’s where the Australoid populations were, and to the extent they interbred with the newcomers they transmitted their less intellectual genes to the gene pool. In India there is a significant difference in tested IQ between castes, with Brahmins at the top, presumably because they have less indigenous, aboriginal ancestry. The higher castes have more ancestors who were Indo-European invaders from the north—in ancient times it was not uncommon for Brahmins to have blue eyes and fair hair, or so I have read. The lower castes tend to be more Dravidian, with more intermixture with the proto-Australoids who lived in India even before the Dravidians showed up.
Although proto-Australoids rounded the bend of the coast of Southeast Asia and worked their way further north, possibly even making it across the Bering land bridge into North America in small numbers, for some reason H. sapiens 2.0 of the subsequent migration wave (we mustn’t call them distinct subspecies by this point, as both groups still exist, so that would be racist) had little interest in interbreeding with them there, unlike those of the south and southeast. Modern East Asians appear to have no more than traces of Australoid and Denisovan ancestry, although they do possess Neanderthal genes. The Australoids and Denisovans farther north were outcompeted and killed off by the newcomers, or otherwise disappeared; I don’t know why. I also don’t know exactly how the Ainu of Japan and eastern Siberia, an archaic aboriginal population, fit into the picture.
Meanwhile, back in Africa, the predominant, archaic, aboriginal populations of Homo sapiens resembled and were ancestral to the Khoisan peoples of southern Africa, and also were akin to the Australoid groups of the second-to-last emigration wave. They could remain relatively archaic as humans because they remained in the ancestral territory and met with fewer environmental changes and challenges of the sort which stimulate evolutionary change. They also evidently interbred to some degree with non-sapiens individuals, although the evidence is sparse. But in the forests of the west of the continent, in a new environment stimulating adaptive change, a new racial type arose, sometimes referred to as Congoid, or Negroid—that is, black people. Apparently they developed traits that allowed them to outcompete the Capoid people (the Khoisan and black races of Africa are racially distinct, although there has been quite a lot of interbreeding) in the ancestral homeland. They were larger, stronger, faster, and presumably more intelligent, and furthermore had more advanced technologies; and so starting around 3000 years ago there was what is called the Bantu expansion, in which black Africans migrated eastwards, then southwards, and displaced the Khoisan peoples throughout most of their territory, leaving them mostly only in desert areas that the blacks didn’t want. (Consequently, African black people can complain about how Europeans came and stole their land, but their ancestors did the same to the Khoisan people, which in South Africa was less than a thousand years previously. Which is generally how things have worked in this world. And there is no question of blacks giving the land back to the Hottentots and Bushmen (or whatever the politically correct names for them are nowadays).)
The pattern of our evolution and propagation appears to be a matter of more evolutionarily derived groups, due to greater adaptive modifications on the basic model, outcompeting and marginalizing, if not eradicating, more archaic forms. This is evident with the advent of every species—H. erectus prevailing over H. habilis, H. heidelbergensis prevailing over H. erectus, H. sapiens doing likewise over all our predecessors, and also Negroids in Africa prevailing over Capoids, and more derived groups prevailing over Australoids in southern Asia. In fact it has probably been pretty much the case since long before our ancestors were human, or even vertebrates. And in our case as humans it seems to be a matter fundamentally involving intelligence, plus maybe a few other factors like fecundity, ferocity, or dumb luck.
All of this is fairly straightforward evolutionary biology, and is pretty uncontroversial so long as we’re talking about extinct groups considered to be different species from us; and it would be uncontroversial with regard to groups officially within Homo sapiens also if it weren’t politically incorrect heresy. The ideology of the new left insists upon a nonexistent equality/sameness between races or ethnicities, and must rely upon science denial, or even hysterical science denial, to support an ideology so much at odds with empirical reality as to amount to potential cultural suicide. The left, including the academic left, is in such denial that it cannot face even plain facts if they go against the feelings-driven ideology; medical researchers can be punished in various ways for acknowledging even medical differences between the races (“that’s racist!”), despite the importance of understanding these differences for the sake of effective medical treatment. To investigate physical or psychological differences between existent human racial groups is now a thought crime, a damned heresy to be stamped out if at all possible.
Consequently, I’ll hammer away at the issue a bit more next time, explaining more the evolutionary mechanisms that produce racial differences, both physical and psychological. And to hell with the pandemic disease of political correctness.
…in 2011, this conventional wisdom was challenged by a new discovery. Using modern gene sequencing techniques, researchers sampled the DNA from a lock of hair that a young Aboriginal man had donated to a British anthropologist in 1923. When DNA in the hair was compared with the genomes of people living in Asia, Europe, and Africa, scientists discovered that Aboriginal Australians are more closely related to Africans than they are to modern Asians and Europeans.
This suggests humans migrated into Eastern Asia in multiple waves and that today’s Aboriginal Australians are descended from an early wave that left Africa about 70,000 years ago, before the ancestors of Asians and Europeans. If confirmed, the finding means that present-day Aboriginal Australians are the oldest population of humans living outside of Africa. (—from National Geographic)
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