The House with Many Doors (or: At the Caucasus, Hang a Right!)
When people think of fiction that depicts human prehistory, Jean Auel’s Cave Bear books invariably poke up their woolly heads. The SF-learned may also recall William Golding’s The Inheritors and two Poul Anderson stories dealing with Cro-Magnons; the literati may be aware of Björn Kurtén’s Dance of the Tiger. But few have read what I deem the best entries in this group: Elizabeth Marshall Thomas’ Reindeer Moon and Animal Wife. The riveting world she created in those novels is far closer to the truth than Auel’s sugar-coated anachronisms.
Recently I had yet another reason to think of Thomas’ works beyond their excellence as both science and fiction. She set her universe in Siberia during a warmer spell when it was not tundra but a mixture of steppe and taiga alive with wolf packs, mammoths, herds of game animals – and the mighty Amur tigers, who leave an indelible pawprint in Animal Wife. In the same story, her band of humans meets a band of others – different enough to awaken the fight-or-flight reflex, though not different enough to preclude progeny and with it, the tortured, conflicted love endemic in such circumstances.
Which brings us to the just-confirmed cousins in addition to the Neanderthals who walked the earth with us and mingled their genes with ours: the Denisovans. Just like the people in Thomas’ stories, the Denisovans made their home in Siberia. One of their homes, for they were wanderers like the rest of humanity until we were immobilized (in more ways than one) by agriculture.
The intertwined human family tree (from Nature)
[Click on the diagram to see a larger version]
Bones and artifacts can tell us much, but nucleic acids can tell us more. Mitochondrial and Y DNA analyses have allowed us to map human migrations and group interactions, nuancing simplistic single-lineage theories. The recent draft of the Neanderthal genome showed they still live in us, sharing 5% of the genome of non-Western Africans. Their FOXP2 gene, which allows speech-enabling facial development, was identical to ours – and many were red-haired, making Jean-Jacques Annaud’s Quest for Fire eerily prescient on all these points.
Sequencing of DNA from two Denisovan bones, a tooth and a finger joint, showed they belonged to the Neanderthal clan and branched about 500,000 years ago, after an early exodus from Africa that predated that of Sapiens by nearly one million years. Somewhere in Eurasia (probably around the Caucasus range which forms the first large obstacle), these early wanderers split into two streams. The Neanderthals went west, the Denisovans headed east. And like the Amur tigers, they roamed wide and were still around when Sapiens bands in their turn migrated east. We know this because 5% of Melanesian DNA is derived from Denisovan ancestors.
There findings have caused a sea change in how we see ourselves and our predecessors. Like all scientific findings, they can be (and have been) used to advance agendas. Some argue that the lack of Neanderthal admixture makes sub-Saharan Africans the pure human strain, others that the Neanderthal input gave Europeans hybrid vigor. Both choose to ignore inconvenient facts. By the ironclad criterion of inter-fertility, Neanderthals and Denisovans were fully human. On the other side, sub-Saharan Africans exhibit as much genetic diversity as most other human groups combined. The take-home message is: we’re all mongrels and we do best when we acknowledge and celebrate this, instead of taking refuge in fallacious superiority fantasies.
Buddhist Monks from Central Asia (fresco, Kizil cave, ~900 CE; the one on the left is a Tocharian)
This split (as well as the agendas that attempt to harness it) has a later, equally fascinating echo. Around 5000 BCE another migration wave broke on the Caucasus, splitting in two – the Indo-Europeans. There’s consensus on that, even if the details are still hotly debated. Less known is how far-flung were the travels of some of the Indo-Europeans who turned east. The outliers were the Tocharians, a Silk Road culture that occupied the Tarim basin of Inner Mongolia from 2000 BCE to 1000 CE before being displaced and subsumed by the Uyghur.
For a long time, the Tocharian civilization was lost from sight as wars and the shifting sands of the Taklamakan desert destroyed them and most of their artifacts. But they left behind items that are hard to ignore: a treasure trove of scrolls that include both texts and illustrations; several frescoes on cave walls; and the mummies of Ürümqi, preserved perfectly in the dry local climate. The Tocharians were blue-eyed dolichocephalic redheads who wore garments of plaid wool and spoke a language whose closest relative appears to be Old Gaelic. In short, the Tocharians were Celts and preliminary genetic analysis has confirmed the link.
Like Kennewick Man (who belonged to the Jomon people, the predecessors of the Ainu), the Ürümqi mummies have been used for politics: the Uyghur have adopted them as symbols in their struggle for independence, the Chinese have tried to suppress them by neglect and red tape in the way of scholars who want to analyze them in more detail.
Map of the Silk Road [Click on it for a larger version]
I don’t believe the presence of Celts in Mongolia threatens the achievements of those who succeeded them. But I love to think of the strains mingling in that stark part of the world which nevertheless gave so much to human culture and acted as a thoroughfare between West and East. And my heart is glad to contemplate that Alexander’s Roxanne, born in adjacent Sogdia, perhaps had hazel eyes and glints of auburn in her hair, a strand from a Tocharian grandparent woven into her tapestry.
Further reading:
Luigi Luca Cavalli-Sforza, Genes, Peoples, and Languages
Elizabeth Wayland Barber, The Mummies of Ürümchi
Susan Whitfield, Life along the Silk Road
Kenneth Wimmel, The Alluring Target
Iskander, Khan Tengri
Neanderthal Genes: The Hidden Thread in Our Tapestry
A (Mail)coat of Many Colors: The Songs of the Byzantine Border Guards
Woolen fabric from a Tarim basin mummy (~1000 BCE).
Fascinating how our history is more complicated–indeed, more messy–than we would like to imagine. And thus a good thing to keep in mind.
In many respects, history is more complex and interesting than a lot of of fiction!
I agree; this is indeed a good thing to keep in mind. Thanks for sharing this incisive look at these aspects of our history.
…we’re all mongrels and we do best when we acknowledge and celebrate this, instead of taking refuge in fallacious superiority fantasies.
Absolutely.
I think you’d find Life along the Silk Road fascinating, Heather. It’s a necklace of linked stories taking place around the 10th century. Each story protagonist makes a cameo appearance in the next one.
Glad to know we’re well and truly mixed 🙂
Stirred in the common pot energetically, no less! *laughs*
I’m perhaps going out of my way here, but I’m thinking back of the film/book Memoirs of a Geisha, where the heroine is born with slate-blue eyes. If such oddities truly happened in real life, then perhaps the Tocharian presence has much more to answer for than we think…
Cheers,
Eloise 🙂
I had forgotten that detail, Eloise, but it does make you wonder! Both the Chinese and Japanese are very prickly about racial purity even in their past, which is very regrettable but not surprising given the local politics and power relationships.
An amazing story and writing, Athena! The idea that more than one intelligent human species appeared on this planet is not only fascinating in its own right, but it also hints that biological evolution on other worlds might also produce more than one smart creature at the same time over long periods of time.
As for Clan of the Cave Bear, I noticed among other things (such as the two main characters being ridiculously perfect specimens of humanity, past or present) that the very few times she referenced anything to do with astronomy it was always shown as remote and uninvolved in the lives of her characters. Whereas there is definite evidence that ancient humans were very interested in the heavens and knowing what was going on up there was often tantamount to their survival here on Earth.
Thank you, Larry! It’s still clear, however, that we’re dealing with very closely related species where hominin are concerned — if they were not closely related, they wouldn’t have been able to interbreed.
While writing this I was tempted to mention the Xindi of Star Trek: Enterprise which were biologically feasible except for the insectoid species (the stereotyped traits are a different story). But then the article veered in a different direction and I let it. I still want to talk about the possibility of more than one sentient species in a future article, though.
DNA analysis seems to be opening the human story to us! It’s so exciting! I look forward to more articles on these matters from you.
I cannot agree with you more, Kathryn! It’s extraordinarily exciting, because we have a lot of material classified only on the basis of morphology or stratigraphy that can now be analyzed with the new tools.
I also really like the thought of several human families roaming the earth and not always meeting as adversaries.
Just another wee article shedding more light (and prompting yet more interrogations) on the matter:
http://www.nytimes.com/2011/02/21/arts/design/21silk.html?_r=1&hp=&pagewanted=all
Cheers,
Eloise 🙂
Interesting article! Maybe I should go take a closer look. Incidentally, Kennewick Man is rather obviously an Ainu — both facial features and genetic tests concur. It’s ironic to have the Native Americans of the Pacific Southwest erasing another persecuted group by trying to shoehorn him into theirs.
Another related article:
http://io9.com/#!5774949/how-did-humans-really-evolve
Excellent summation of the various theories.
Selection for smaller brains in Holocene human evolution
Authors: John Hawks
(Submitted on 28 Feb 2011)
Abstract: Background: Human populations during the last 10,000 years have undergone rapid decreases in average brain size as measured by endocranial volume or as estimated from linear measurements of the cranium. A null hypothesis to explain the evolution of brain size is that reductions result from genetic correlation of brain size with body mass or stature.
Results: The absolute change of endocranial volume in the study samples was significantly greater than would be predicted from observed changes in body mass or stature.
Conclusions: The evolution of smaller brains in many recent human populations must have resulted from selection upon brain size itself or on other features more highly correlated with brain size than are gross body dimensions. This selection may have resulted from energetic or nutritional demands in Holocene populations, or to life history constraints on brain development.
Comments: 17 text pages, 3 bibliography pages, 1 figure
Subjects: Populations and Evolution (q-bio.PE)
Cite as: arXiv:1102.5604v1 [q-bio.PE]
Submission history
From: John Hawks [view email]
[v1] Mon, 28 Feb 2011 06:22:01 GMT (25kb)
http://arxiv.org/abs/1102.5604
Scientists say cavemen stayed put
Darryl de Ruiter
This specimen, known as SK 48, is one of the best examples of Paranthropus robustus from South Africa’s Swartkrans Cave.
By Alan Boyle
An analysis of fossil teeth from South Africa suggests that the males in pre-human societies stayed near the caves where they grew up, while the females migrated when it was time to mate.
The researchers behind the analysis say their findings, published in this week’s issue of the journal Nature, could shed light on the migratory behaviors that eventually gave rise to human societies.
“This appears to be most similar to a chimpanzee social structure,” said lead author Sandi Copeland, an anthropologist at the University of Colorado and Germany’s Max Planck Institute for Evolutionary Anthropology. It’s also consistent with the way many humans handle the process of moving out and settling down, she told journalists. “It’s more often than not in modern societies that the woman is the one that leaves,” she noted.
Full article here:
http://cosmiclog.msnbc.msn.com/_news/2011/06/01/6763124-scientists-say-cavemen-stayed-put?email=html