To be clear, this post may be about science, but it is not science any more than sports commentary is a sport.
This post has been many months in coming. An embarrassing number in fact. And in that time, I have managed to come full circle. Where before I had intended to write a post excoriating a comment made by Jennifer Raff, anthropological geneticist at the University of Texas, I will instead begin by applauding it.
But I am getting ahead of myself.
Place Your Bets
The March 22nd, 2014 issue of Science News ran an unimaginative story with a quote so bold and provocative that, 9 months later, I still had to blog about it.
My primary motivation here is to put my opinion into the public record while it still entails a certain degree of risk. Being only a casual reader on the topic, I’m guessing there is probably still plenty.
In this regard, taking sides in a scientific debate is very much akin to sports fandom. In my mind at least, the amount of vicarious glory derived from taking a stance is directly proportional to the reputational risks assumed in staking out a position.
It’s hard to say “I told you so” on a topic that’s already been settled. Bets must be placed while the proverbial roulette wheel is still spinning.
This post and that quote are not so different – only this post is much longer, less timely, and more self-indulgent.
I grew up in a house whose downstairs bathroom windowsill was overflowing with back issues of Science News.
These magazines had a huge influence on me.
However, as my understanding of health and diet has (out of necessity)
evolved in recent years, it’s been has frustrating for me to see that Science News often presents entrenched conventional wisdom as undisputed fact, on topics where reasonable people can disagree or see more nuance – for instance preceding “saturated fat” with the obligatory “artery-clogging” prefix, or carrying breathless discussion of all the latest statin research which the industry has deemed positive enough to release.
This is not to say that I have ever been, or will ever be, entirely correct about diet and lifestyle. I’ve managed to improve my health greatly, but by the same token I am the first to recognize that, in my willingness to embrace the unorthodox, I have made a number of peculiar, large, and in some cases, quite damaging mistakes. (Stay tuned for more on those in upcoming posts…)
For now, let’s return to the story.
Out On a Limb
The March 22nd, 2014 issue of Science News includes a story by Tina Hesman Saey about an analysis of the DNA of the Clovis infant Anzik-1. It seems she reached out to Jennifer Raff for a comment – and was not disappointed.
Jennifer is quoted as saying “It’s not the last nail in the coffin, it’s the last spade full of earth on the grave of the Solutrean hypothesis.” (SN: 3/22/14)
Bold words. For some reason, I haven’t been able to let them go. So, in that same spirit, I feel I must go out onto the opposite limb before the matter is settled.
The Anzik-1 infant was seen to disprove the Solutrean hypothesis because “The Clovis baby, known as Anzik-1, like today’s Native Americans, can trace part of his heritage to a child known as the Mal’ta boy, who lived in Siberia 24,000 years ago.” (SN: 3/22/14)
And of course, (given the size of the Bozeman airport), a Siberian population could only have arrived in Montana via Beringia.
By the Way
In other news, in a May 17, 2014 article, Tina (Hesman Saey) covered an analysis of the ancient and modern European genomes.
Modern-day Europeans, the team concludes, are a complex mix of at least three ancient groups: the early European farmers, Western European hunter-gatherers, and a third group the researchers call the ancient north Eurasians.
Eske Willerslev, an evolutionary geneticist at the University of Copenhagen, and his colleagues revealed that mysterious third group in January via the genomes of two Ice Age Siberians (SN: 12/28/13, p. 16) (<- their citation).
One of the Siberians was a young boy buried 24,000 years ago near Lake Baikal. The child, known as Mal’ta-1, is genetically unlike any living group of people today. His genetic profile lies somewhere between that of western Eurasians and Native Americans, Willersleve and colleagues reported in Nature. That finding helps explain why some Native Americans have similar genetic signatures to Europeans; both groups got DNA from the Mal’ta child’s people.”
(SN: 5/17/14, p. 30-31) (<- my citation)
But clearly the edge of the “seasonally rich” (Across Atlantic Ice, Stanford & Bradley p. 15) marine ice was as far west as those “Siberians” reached.
Now let’s take a minute to discuss the differences in burial practices between the Solutrean and Clovis populations.
Of Gods and Babies
The Anzik-1 infant was the first, and (as of 2/12/14) the only example of a Clovis burial, and should therefore be seen as representative of Clovis mortuary practices. From this we can conclude that all Clovis members lived to the age of 18 months and were buried with more than 100 stone and bone tools. (Just imagine how dexterous those fat little fingers must have been!)
On the other hand, while we have evidence of Solutrean cave art depicting marine animals (ibid. 142), and limpet and periwinkle consumption (ibid. 211), “no Solutrean… burials have ever been found” (ibid. 180) which obviously suggests that either the Solutreans disguised themselves as Gravettians at burial or were immortal and, much later, retired to the Mediterranean coast of France.
Is it reasonable to conclude that a population of Iberian demigods fashioning sophisticated overshot flaked bifacial blades gave rise to a population of ankle-biting big-game hunters who fashioned sophisticated bifacial blades using tricky overshot flaking?
Perhaps not, but I will do so all the same.
Stating the Obvious
In fact, I will go out a little further on my limb and sketch out a way it might have happened.
Precisely 40,017 years ago, modern humans came into Europe and, over the course of 10,031 years, displaced their Neanderthal cousins.
I hope to explore this transition further in upcoming posts and videos. For now, let’s fast-forward to 25,000 years ago.
25,000 years ago, during the last major glacial period (Stanford & Bradley p. 122),
a new population of semi-nomadic hunters, perhaps carrying the mtDNA X2a haplogroup (ibid. 247), entered the scene.
This particular population came from a line of “Siberian” nomads who, perhaps having developed powerful cultural innovations, were very successful, and following various large prey animals, quickly spread themselves far and wide across Eurasia.
As these groups spread, their cultural adaptations diverged much more quickly than their genes. Whereas some of the groups in Asia (perhaps carrying the X2, but not X2a haplogroup) eventually developed a sophisticated microblade technology, one group, perhaps in North Africa (ibid. 144) developed not only (non-perishable) sophisticated bifacial flaking technology, but also (perishable) watercraft.
By the time they arrived on the coast of Western Europe, this group of proto-Solutreans had a sophisticated toolkit (and “Siberian” genes).
At some point, perhaps 22,004 years ago, an intrepid group of Solutreans, whose sophisticated cultural adaptations had prepared them to survive and thrive on marine mammals, made it to North America. They may, in fact, have made this journey more than once in both directions. At any rate, some portion of this population eventually stayed.
Their ancestors traveled down the coastline, past the costly tolls in Delaware and the traffic outside D.C., down to the Southeast. From there they began to thrive and spread, eventually dominating the entire continent before the Younger Dryas period.
(Which, I was planning to add, might have been brought on by an impact event, but recent evidence seems to be suggesting otherwise.)
Thus, at least in my head, it is possible to believe that the Americas were populated by three successive waves of “Siberian” populations, and simultaneously believe that one early wave arrived via the Atlantic sea ice.
Agree or disagree, but for God’s sake make a call while the wheel is still spinning.