Humans do wander and seek

Our ancestors wandered far and wide, seeking something new, and these migrations had consequences for our genetic pools.  I have seen several reports of an archeological find in China (https://www.nytimes.com/2018/07/11/science/hominins-tools-china.html.  Check out the cliff the archeologists had to scale for this research) of tools estimated to be around 2 million years old.  This means that one of our ancestral lines left Africa much earlier than previously thought and traveled 8,000 miles east.  These are categorized as hominins, precursors to genus Homo, but still bipedal with a brain beginning to enlarge.  Paleoanthropologists have found fossils in China of Homo erectus that are 1.6 million years old.  Fossils of hominins in Africa date back to over 6 million years ago.

Repeated migrations over the aeons carried different genes to different populations.  Consider the gene for lighter skin colors that spread in northern populations or the genes enabling lactose digestion that appeared in Europe that spread in a variegated manner.  My favorite is a gene first identified in the Denisovans from central Russa that some migration carried to Himalayan populations; this gene helps form the special type of hemoglobin that enables better adaptation to life at high altitudes (see post 7/4/14). I have wondered if some of the peoples that escaped to live in the high Andes also had such a gene.  I say ‘escaped’ because of a find of a small site from ancient times in the Andes where life would not have been easy because game and edible plants were sparse. (See post 10/27/14) Why live there?  The best hypothesis would seem to be escape from another tribe whose aggression was unbounded.  Anyway, our ancestors clearly wandered the land over many generations seeking opportunities and avoiding negative exigencies.

I have been reading some research by Shinobu Kitayama and colleagues that is quite interesting about the cultural differences between Asian and American peoples. These seem to be fairly well established by multiple lines of research with different samples and different methodologies.  In brief people from Asian cultures see themselves and the world as more interdependent (Americans see it as more independent), focus more on context than on a lone figure, define the self in relation to social relatedness rather than individual achievement, seek to accommodate rather than to be an agent of social change, de-emphasize individual achievements by focusing on their own faults and attributing success to social connections, think holistically rather than linearly, etc.  Looking at this list you can see that Americans are quite different culturally, thinking linearly, highlighting personal achievement, valuing competition and social friction a bit more, etc.  Just to speculate a bit more based on some lectures on Eastern intellectual traditions by Grant Hardy, the Western endorsement of desert monotheism and the Eastern endorsement of ancestor worship along with values of social order and justice that are accompanied by a flexible notion of deity would seem to reflect our different cultural ways of thinking evident 2-3000 years ago.  Dr. Hardy says Christian efforts to convert China failed when the Pope and the Dominicans condemned ancestor worship as idolatry.  That turned out to be an unacceptable violation of cultural mores and did not fit with the Asian understanding of what a deity is, so they rejected missionary efforts (and then the British gunboats showed up).

Kitayama and colleagues have begun to study how acculturation leads to changes in the brain, so that different cultures lead to different brain organization, thus the cognitive differences noted above.  These differences arise from genetics to developmental epigenetics and acculturation experiences early on life.  This makes perfect sense.  The question arises for me of how migrations have contributed to these differences and how once the differences were initiated the differences became self-sustaining.  Many peoples have revered their ancestors; the Chinese have maintained that even in the face of Christian zealousness.  Certainly part of the answer here is the lack of intermarriage and the protection of the gene pool through isolation.

Consider one final example cited by Kitayama.  Some significant percentage of Americans has a gene allele that promotes increased impulsivity and risk taking; this may contribute to a higher incidence of ADHD (as well as substance abuse, etc.?).  This allele is virtually unknown in the Chinese population. Should there be more intermarriage, that might change.  Why do we have that allele, or how did our migration pattern contribute to its presence? That brings to mind an old joke told at psychology conferences years ago.  A prominent ADHD researcher, in the effort to make fun of the image of Californians, speculated thusly:  The Europeans who populated North America were rebellious, impulsive risk takers—who else would sail across the Atlantic in small ships on a perilous voyage?  And then from that population the even bigger risk-takers, impulsive people migrated west, so that Californians represented a genetic ‘distillation’, as it were, of impulsivity.  Ha-ha.

Jaak Panksepp in Affective Neurosciencedocuments quite clearly how our mammalian heritage includes a proclivity for exploring in our neural systems for seeking and anticipating.  Like a good many traits we have accentuated I think humans have a rarefied impulse to go beyond; this involves some risk but the species that spread across the globe and then went to the moon can manage a good deal of risk. Humans do wander and seek.  We intermarry and that contributes to the flow between gene pools.  We don’t intermarry and otherwise conserve our cultural heritage.  Asians are indeed different than Westerners.  As a member of the latter group, I think we could learn a thing or two from the former, e.g., mindfulness, the greater value of interdependence, the importance of contextualized thinking, etc.  But for now I will travel on.

 

Neanderthal update

I like Neanderthal stories for two reasons. First, this research shows science at it best in the development of technologies to date artifacts, the diligent search for ancient clues, and especially, the fact that our conception of who the Neanderthal were has dramatically changed as new data have come in. Since their discovery over a hundred years ago we have gone from thinking them brutes barely different from gorillas to now almost completely human like us. Changing minds through new data is to be much appreciated. The second reason is that genetic studies prove that my ancestors mated with them and I do not want to think of my people long ago mating with brutes of little intellects and no symbolic capabilities. I would hope they were more discriminating.

So the most recent update comes from this story in the NYT: https://www.nytimes.com/2018/02/22/science/neanderthals-cave-paintings-europe.html.

Evidently some paleoanthropologists were holding up their admission of the Neanders into full humanity because they said the evidence allowed the possibility that their use of tools and their art making were copied from Homo sapiens. That objection has now fallen as art and tools have been found and dated through new, refined technology to time periods way before modern humans entered Europe. Hmm, maybe Homo sapiens copied tools and art from them?

My latest thinking on the inception of symbolic thought, both discursive (language) and presentational (art) forms, is that our heightened empathic abilities led to a rather robust intimacy, a mind to mind connection through kinesic modalities wherein we sensed and knew the other’s subjective mental domain, coupled with the increasing power and specificity of mirroring systems serving communication (think arcuate fasciculus). This yields the view that an intimate connection of immediate sensing of another’s mind coupled with the invariant structure of surface behaviors produced the first symbols.

In this light consider why early art is so often found in caves, and not just close to the entrances but sometimes way back in there. We visited one site in France where an electric railcar took us maybe a mile back into the cave to see etchings of mammoths and other animals on the ceiling. Why? Some say that art rose in association with animist magic, that these paintings were a mystical participation with the animal spirits and communion with Gaia. Read Kim Stanley Robinson’s excellent novel Shaman to see the truth of this possibility. But magic has both public and private aspects. Yes, shaman protected their mysteries (and for good reason because sometimes they were not so mysterious once initiated) but they also performed public rituals. Indeed, magic would not be very useful if not public.

Here’s another thought: Art came about when the need arose to extend intimacy beyond the circle of familiars, art being a personal expression of some vital experience, and so the first artists were a bit shy about their productions and protected their privacy by painting deep in caves. As we learned more about art and more came to appreciate the beauty therein, we moved it out into the public domain and cultural identity took on another feature. Even today while some artists open their studios to audiences, many keep their creations private until complete, and some, like Leonardo da Vinci, keep their most precious pieces in their possession. Leonardo kept the Mona Lisa with him for 20 years, working on it a little bit now and again, and died with it in his room, never giving it to his patron. Personal, private, it was.

Anyway, I really like my hypothesis about the inception of art here; it feels fit to me, this combining empathic intimacy and mirrored communication. (You heard it here first). Time, now, to travel on.

Neanderthal_280_470743a

That sapiens guy copied my bison drawing. Good grief! Did a good job though. These new kids may have some talent.

time to update timeline

A story on science news.com gives an accessible account of an article published in Science about a genetic study from the genome recovered from a boy who lived in southern Africa 2000 years ago:  https://www.sciencenews.org/article/ancient-boys-dna-pushes-back-date-earliest-humans.  The methodology here is way beyond my ken but it involves comparing this genome to others recovered all around Africa and Eurasia from different time periods and figuring out rates of genetic change that would account for its composition some 2000 years ago.  The scientists concluded that the essential genome for us, Homo sapiens, coalesced around 350,000 years ago; that is a 100,000 years earlier than previously thought.

Putting some of the reports together, it seems that humans in Africa long ago traveled the  length and breadth of the continent and intermarried for many thousands of years ago before modern humans migrated to Europe, maybe influenced by climate changes..  My 6/19/17 post was about a Moroccan fossil that also put Homo sapiens origin around 300,000 years ago.  For reference DNA studies indicate that Neandertals and Denisovans (our kinfolk in Europe and the Russian steppe;  homo sapiens did not arrive in Europe until around 30,000 years ago) split around 640,000 years ago.

Adding to a post from some time back check out these dates listed as years ago:

3 million—gene appears promoting brain enlargement

2 to 2.8 million—tools that were worked and shaped

1.8 million—fire and cooking (homo erectus)

before 640,000-Neandertal and Denisovan genomes took shape

500,000–phonological study’s estimate of origins of modern language

350,000-Homo sapiens genome took shape

130,000-eagle claw necklace from southern Africa

40,000 to 100,000—burials

45,000—paintings, good painting they are too

43,000—bone flutes

40,000—dogs domesticated

40,000—modern humans arrive in Europe

10,000—agriculture

9,000—dog burials (just found that one)

6,000—glyphs and a new learning curve

500–modern science took hold

And so we travel on.