Speciation in Humans

A growing body of archaeological evidence indicates that genetically and anatomically modern humans shared the world with other, distinct hominin species. Their historical divergence is profound, ranging from a minimum of 500,000 years to a maximum likely close to 2 million years. We now suspect that when H. Sapiens Sapiens left Africa some 70,000 YA they would have encountered at least three other (possibly four) extant species of human significantly different in evolution and cultural development.

Some introductory info:

In Indonesia there was the now famous "hobbit", a distant cousin of modern humans likely diverging as much as 1 million years prior (with the Out of Africa migration of Homo Erectus). They persisted on Flores Island as recently as 12k YA. Given that modern humans had contact with this area by roughly 45k YA there is a 30,000 year time frame in which contact could have taken place. They used sophisticated Upper Paleolithic stone tools and had mastered fire. It is possible, but not confirmed, that they had some rudimentary language skills. While they would have appeared very different from modern humans, their use of language, tools, and fire would have set them apart from local animals.

The Neanderthal in Europe is probably the best well known parallel species to modern humans. Divergence is roughly 500,000 years ago, with full development of the 'Neanderthal' appearing around 120k YA in the Middle East and Europe. The last populations on Gibraltar likely died out 24,000 years ago, with the majority vanishing from Europe some 30,000 years ago. This gives them a roughly 20,000 year overlap with modern humans in Europe (with most human migrations running from Central Asia into Europe some 50,000 years ago). Their tool cultures were analogous to their contemporaries in modern humans running from the Mousterian to the Gravettian tool kits. That is, they had use of wood, bone and stone tools, as well as fire, and used animal hides for both clothing and shelter. They had burial rituals, portable art (jewelry and decorative carvings) and possibly some knowledge of herbal medicine. It is certain they had language, the FOXP 2 gene is shared with humans and is strongly associated with language acquisition; they also had a developed larynx and hyoid, the necessary bone structures for articulate speech. Evidence exists that they traded goods and even technology with early modern humans prior to the last Ice Age. mDNA analysis suggests that Asian peoples have 1-3% shared DNA and Europeans up to 4% shared DNA, indicating at least some interbreeding. Africans have no DNA overlap whatsoever.

The newest discovery is the Denisovan artifacts found in the Siberian mountains. Genetically distinct from both modern humans and the Neanderthal, the Denisovan culture overlapped with modern human occupation of the Central Asian Steppes some 40,000 years ago. The Denisovan may have shared a common ancestor with Neanderthal, but possibly introgressed into extant Homo Erectus populations in Central and East Asia 400k YA. Very little is known about their technology or culture, but genetic analysis revealed a somewhat surprising fact: modern Melanesian (New Guinean) peoples share up to 6% genetic overlap, indicating early contact interbreeding.

There is some scant evidence as well that early Out of Africa migrant Homo Sapiens may have encountered residual Homo Erectus populations in East Asia and Indonesia. These would have been tool using, hunter-gather tribes of hominin peoples who would almost certainly have lacked any ability to produce spoken language any more advanced than modern Chimpanzees. Though most would have been extinct 100k YA, there is some evidence that populations in remote regions surived to as late as 50k YA.

So...some random thoughts on the subject. As a historian, as a theist, as a storyteller, as a gamer...

How would our ancient ancestors have reacted to these peoples? Even Homo Erectus would have been distinct from anything *animal* with its use of tools and upright posture. The Neanderthals would have been incredibly similar - able to talk, using fire and contemporary tool kits of similar style, clothed in animal hides and hunting similar game. Would there have been immediate hostility, recognition of a dangerous competitor? Trade likely happened between Neanderthals and humans at least, likely between the others as well. At least some interbreeding happened, though the circumstances are lost in time. Would they have recognized each other's similarities? Or emphasized their differences? Our ancestral humans would have possessed more advanced technologies for weapon use (or so the archaeologists tell us) but otherwise they would have been starkly similar.

And the span of overlaps is huge...20,000 years! Longer than the pyramids have stood, longer than North America has been inhabited. There are whole histories lost there, unwritten, stories forgotten. I'm tempted to appeal to Jung's theories of the primitive man, the echoes of ancient narratives embedded in our pscyhe deep below our conscious thought. Are Neanderthals the origins of the legends of dwarves, goblins, trolls...? Idle speculation, and unlikely of course, but...still.

It certainly suggests something for a fantasy setting. As gamers we're used to have multiple race cultures side by side, but this is a challenging question - how would they really have related? I certainly don't know, but it seems fertile ground for fiction to explore. The worlds of the late Pleistocene would have been wonderously complex. Neanderthals inhabited Europe longer than genetically modern humans have existed. The Toba catastrophe bottleneck and the final blows of the Younger Dryas created a new world where only one species of human did survive, but there are so many what ifs and what dids?

On a theological note...most Christian theologians exclude animals from salvation. So where does that leave Neanderthal and Floresiensis? Were they humans with souls? Were they animals without souls? Either way, what does that say about the masses of modern humans who posses 1-4% Neanderthal DNA? Those with 6% Denisovan? The only "pure" humans are those from Africa. If the plan of salvation is only for humans...what about those of us who aren't pure human? What about our great-ancestors amongst the Homo Erecti who certainly weren't modern humans in any real sense of the word?

And as this evidence grows, it sharpens questions...do races actually exist on a biological standing? For years, the strongest defense against racial theory was the simple fact that biological races don't exist at all, but if mDNA mapping changes that, if races do in fact have a genetic grounding...what does that mean? What should it mean? Anything? Nothing? Something?

I'm sort of idly ruminating here. I have some early thoughts for a novel set just prior to the last glacial maximum some 30,000 years ago, but so sketchy as to be just random ideas bouncing around in my head at this point.

Just tossing all of this out...what do you think? Philosophically, what does this say about our conceptions of being human? Spiritually, what does it say about ourselves and the world?