Study Offers New Twist in How the First Humans Evolved
A new genetic analysis of 290 people suggests that humans
emerged at various times and places in Africa.
Scientists have revealed a surprisingly complex origin
of our species, rejecting the long-held argument that
modern humans arose from one place in Africa during one
period in time.
By analyzing the genomes of 290 living people,
researchers concluded that modern humans descended from
at least two populations that coexisted in Africa for a
million years before merging in several independent
events across the continent.
“There is no single birthplace,”
Study Offers New Twist in How the First Humans Evolved
A new genetic analysis of 290 people suggests that humans
emerged at various times and places in Africa.
This is idiocy. I usually point to the "Study" that showed how
Europe wasn't populated until about 4k years ago.
Of course it was continuously populated for tens of thousands
of years. It's about what DNA survives right now...
Look. Everyone who carries the Chromosome 11 insert, the
"Nuclear Insert" made famous by Mungo Man has Eurasian
ancestors going back significantly further than any supposed
mitochondrial eve. But we only know that because of the
insert. All the rest of the DNA is either gone or
indistinguishable from so called "Modern" DNA.
The point is you can look at DNA, you can tell exactly where
and how it is different from someone else's DNA but there
isn't a goddamn thing that tells you how it got that way.
AND, the assumptions are proven wrong.
Scientists have revealed a surprisingly complex origin
of our species, rejecting the long-held argument that
modern humans arose from one place in Africa during one
period in time.
The message here is: DA HUMENZ CUM FROM AFRICA!11!!!1!
What it's saying about DNA is utter bullshit.
By analyzing the genomes of 290 living people,
researchers concluded that modern humans descended from
at least two populations that coexisted in Africa for a
million years before merging in several independent
events across the continent.
The Bantu Expansion was like 3,000 years ago. Really. This
story is utter bullshit.
“There is no single birthplace,”
They're saying the exact opposite: Africa is that one single
birthplace.
So the story isn't even internally consistent.
https://www.nytimes.com/2023/05/17/science/human-origins-africa.html
Study Offers New Twist in How the First Humans Evolved
A new genetic analysis of 290 people suggests that humans
emerged at various times and places in Africa.
Scientists have revealed a surprisingly complex origin
of our species, rejecting the long-held argument that
modern humans arose from one place in Africa during one
period in time.
By analyzing the genomes of 290 living people,
researchers concluded that modern humans descended from
at least two populations that coexisted in Africa for a
million years before merging in several independent
events across the continent. The findings were published
on Wednesday in Nature.
“There is no single birthplace,” said Eleanor Scerri, an
evolutionary archaeologist at the Max Planck Institute
for Geoarchaeology in Jena, Germany, who was not involved
in the new study. “It really puts a nail in the coffin of
that idea.”
Paleoanthropologists and geneticists have found evidence
pointing to Africa as the origin of our species. The
oldest fossils that may belong to modern humans, dating
back as far as 300,000 years, have been unearthed there.
So were the oldest stone tools used by our ancestors.
Human DNA also points to Africa. Living Africans have a
vast amount of genetic diversity compared with other
people. That’s because humans lived and evolved in
Africa for thousands of generations before small
groups — with comparatively small gene pools — began
expanding to other continents.
...
THe Nature article is open access.
https://www.nature.com/articles/s41586-023-06055-y
A weakly structured stem for human origins in Africa
Abstract
Despite broad agreement that Homo sapiens originated
in Africa, considerable uncertainty surrounds
specific models of divergence and migration across
the continent1. Progress is hampered by a shortage
of fossil and genomic data, as well as variability
in previous estimates of divergence times. Here we
seek to discriminate among such models by considering
linkage disequilibrium and diversity-based statistics,
optimized for rapid, complex demographic inference.
We infer detailed demographic models for populations
across Africa, including eastern and western
representatives, and newly sequenced whole genomes
from 44 Nama (Khoe-San) individuals from southern
Africa. We infer a reticulated African population
history in which present-day population structure
dates back to Marine Isotope Stage 5. The earliest
population divergence among contemporary populations
occurred 120,000 to 135,000 years ago and was preceded
by links between two or more weakly differentiated
ancestral Homo populations connected by gene flow
over hundreds of thousands of years. Such weakly
structured stem models explain patterns of
polymorphism that had previously been attributed to
contributions from archaic hominins in Africa. In
contrast to models with archaic introgression, we
predict that fossil remains from coexisting
ancestral populations should be genetically and
morphologically similar, and that only an inferred
1–4% of genetic differentiation among contemporary
human populations can be attributed to genetic
drift between stem populations. We show that model
misspecification explains the variation in previous
estimates of divergence times, and argue that
studying a range of models is key to making robust
inferences about deep history.
Sysop: | Keyop |
---|---|
Location: | Huddersfield, West Yorkshire, UK |
Users: | 303 |
Nodes: | 16 (2 / 14) |
Uptime: | 85:58:19 |
Calls: | 6,808 |
Calls today: | 4 |
Files: | 12,328 |
Messages: | 5,401,640 |