Later, 9:51 p.m. CDT: $70.01.
After hours trading:
The Biology Page
I am blown away by what researchers are finding these days. First it was the color of dinosaur feathers.
Now, it's the "history" of Homo neanderthalensis and Homo sapiens: two different species, and species, by definition don't interbreed.
The book: Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past, David Reich, c. 2018.
H. neanderthalensis and H. sapiens split 100,000 years ago.
- mitochondrial DNA (mtDNA): maternal, mother to daughter
- high rate of mutation (at least relative to non-mtDNA)
- relatively easy to collect from bones
- especially high density, of all things, in the tiny bones of the inner ear (who would have thought)
- mtDNA clearly indicates that at least "some" neanderthals and "sapiens" interbred -- producing fertile offspring
- occurred at least 50,000 years ago in Africa
- Now, the Denisova Cave, 2008
- in the Atlai Mountains of Siberia
- one of the best samples of ancient DNA ever discovered -- in a bone from a child's little finger
- whole genome mapped
- neither neanderthal or "sapien" -- wow
- a new "human" -- the Denisovians
- specifically chose that name so as not to name a new species
- it appears:
- modern human lineage split from "whatever existed before" about 770,00 to 550,000 years ago
- the other lineage, then split into Neanderthals and Denisovians between 470,000 and 380,000 years ago
- and then this: Denisovians (Siberian) closer genetically to New Guinea than to Eurasia
- the Denisovians separated into two lineages between 400,000 and 280,000 years ago
- one branch, the Australo-Denisovians: interbred with modern humans; direct ancestors of present-day New Guineans
- the Australo-Denisovians: a "ghost population" -- known only from genetics; no identifiable skeletal remains
- the story culminates in a population dispersal from the southeast about 14,000 years ago that spread a relatively homogeneous population across Europe and the Near East
- [interestingly, the book on Stonehenge recently read begins 10,000 years ago -- in the same ballpark]
- 8800 BC: first farmers spread into Europe from Anatolia (Turkey)
- 6800 BC: the hunter-gathers disappeared; occurred rapidly once it began
- 5000 BC: Yamnaya culture originating in central Asia swept across Europe, replacing existing populations
- across Europe, the "Corded Ware culture"
- these are most likely the speakers of proto-Indo-European (not the Anatolians)
- Reich explains why the folks of the Corded Ware culture were so successful
- Beaker folk