Molecular Anthropology and the Subversion of Paleoanthropology: an Example of "the Emperor's Clothes" Effect? Author(s): Jeffrey H. Schwartz Source: History and Philosophy of the Life Sciences, Vol. 34, No. 1/2, Human Evolution Across Disciplines: Through the Looking Glass of History and Epistemology (2012), pp. 237-258 Published by: Stazione Zoologica Anton Dohrn - Napol
So I first promoted Schwartz on Professor PZ Myer's infamous "number 1 science blog" - and I got some attention since Schwartz, also being a professor, is not easily dismissed. That was back in 2006 - and look - he's still going into great detail on the problems with the DNA claim for Chimps being the closest relative to the Homo Sapien lineage...
One of the interesting anomalies to the standard science claim - something I did not realize - is that both Chimps and Gorillas HAVE to walk on the knuckles because their tendons do not allow extending the wrist while also extending the fingers!! Quite amazing.
So this was his main argument before -
So Schwartz is arguing that just because they have similarities does not mean there is a linear time connection - it's the opposite of the above logical error - that because something happened "after" therefore the previous thing "caused" it.post hoc, ergo propter hocphrase of post hocafter this, therefore resulting from it: used to indicate that a causal relationship has erroneously been assumed from a merely sequential one.
Oh so that explains how ALLELES manifest! I always wondered about this. Glad that Schwartz is giving a "behind the scenes" expose.
OK so now that we debunked the Genome argument for the humans as chimp cousins - let's look at Schwartz' argument for the human-orangutan cousin relationship.
https://www.sciencedaily.com/releases/2009/06/090618084304.htm
Of these features, the analysis found that humans shared 28 unique physical characteristics with orangutans, compared to only two features with chimpanzees, seven with gorillas, and seven with all three apes (chimpanzees, gorillas, and orangutans). Gorillas and chimpanzees shared 11 unique characteristics.So my immediate reaction before was , "yes but the genetic evidence is SO strong for the chimp connection..." but now that I've read the above - I know that is not true!!
They found that orangutans shared eight features with early humans and Australopithecus and seven with Australopithecus alone. The occurrence of orangutan features in Australopithecus contradicts the expectation generated by DNA analysis that ancestral humans should have chimpanzee similarities, Schwartz and Grehan write.
they propose that the last common human-orangutan ancestor migrated between Africa, Europe, and Asia at some point that ended at least 12 million to 13 million years ago. Plant fossils suggest that forests once extended from southern Europe, through Central Asia, and into China prior to the formation of the Himalayas, Schwartz and Grehan write, proposing that the ancestral dental hominoid lived and roamed throughout this vast area; as the Earth's surface and local ecosystems changed, descendant dental hominoids became geographically isolated from one another.That's fascinating!
There is no theory holding that molecular similarity necessarily implies an evolutionary relationship; molecular studies often exclude orangutans and focus on a limited selection of primates without an adequate "outgroup" for comparison; and molecular data that contradict the idea that genetic similarity denotes relation are often dismissed.John R. Grehan1 and Jeffrey H. Schwartz. Evolution of the second orangutan: phylogeny and biogeography of hominid origins. Journal of Biogeography, 2009 DOI: 10.1111/j.1365-2699.2009.02141.x
OK who cites this?
70 citations!
Fossil evidence for the origin of Homo sapiens - Schwartz, 2010
From this perspective, these authors ultimately argued that if H. sapiens is today the result of nearly 2 million years of post‐H. habilis lineage transformation, it is nonsensical to recognize H. erectus as a distinct taxon. Rather, if human evolution after H.habilis and into the present was indeed continuous and genetically interwoven, one should refer all non‐H. habilis specimens to the species to which their living descendants belong: namely, H. sapiens.Again fascinating!
...preclude it [Erectus] from being ancestral to any other known species of Homo, H. sapiens included (e.g., see Santa Luca, 1980; Schwartz and Tattersall, 1999b, 2000c, 2003).ok...
Our Missing Link to Homo Erectus?
one might suggest a relationship of this potential H. heidelbergensis clade with the Neanderthal clade, but aside from presenting a brow that is thickened superoinferiorly to some extent (a descriptor that can be applied to a number of other hominids), we are hard put to delineate specific morphologies that support this hypothesis. More importantly, the same suite of apomorphies that distinguishes the “heidelbergensis” group would certainly also preclude any of its members from being ancestral to H. sapiens and would likely exclude all from a clade that included the latter.NOPE - a "cousin" like the Neanderthals...
The most recent discoveries attributed to early anatomically modern H. sapiens were found at Herto, Middle Awash, Ethiopia, and date to 154–160 ka (White et al., 2003). Of the three adult crania, only one (BOU‐VP‐16/1) was sufficiently complete to allow White et al. to present systematically useful morphology. Although they described the supraorbital region of this specimen as bipartite, they based their suggestion that the Herto adult is more modern than archaic on metrical comparisons with African fossils they accepted as representing both H. erectus and archaic H. sapiens, plus non‐African modern humans and various Neanderthal specimens.
We possess reason. And if evidence in the archaeological record of symbolic behaviors (Tattersall, 2009) may be taken as a reliable proxy for the possession of “reason,” then this acquisition substantially followed the appearance of H. sapiens as a morphological entity as it is conceived here. The earliest H. sapiens, certainly those from Herto and Omo Kibish, were evidently doing business much as their predecessors had done (Klein, 2009). Only later were complex “modern” behavior patterns adopted. The simplest hypothesis seems to be that the biological underpinnings for the cognitive peculiarities of H. sapiens were attained exaptively, as part of the genetic reorganization that led to the emergence of the very distinctive bony anatomy of our species. But their radical potential was only “discovered” post hoc, much as birds discovered the potential of feathers for flight, and the tetrapods discovered the use of limbs for terrestrial walking, well after their initial acquisition. Thus, yet again, however remarkable, and apparently demanding of special explanation as we may think ourselves, we see in our own origin the operation of entirely routine evolutionary processes, emphasizing the importance of remaining vigilant against unconscious “human exceptionalism.”
a huge variety of morphologies has been admitted into H. sapiens, albeit sometimes into archaic varieties of the species. Acceptance of this muddled variety has been facilitated by a view of evolution that emphasizes gradual transformations in lineages, in which species are basically units of convenience rather than of biology, and that are expected in principle to be undefinable in morphological terms. To systematists studying other groups of mammals, this situation would be untenable;So then it's stated some kind of neanderthal - homo sapiens - hybridization could have occurred 100,000 years ago...
Stan Gooch and I then are ultimately also converged! Fascinating.
I wish I could have told Stan Gooch about this....
New research suggests that early humans in Africa interbred with a ghost population that likely split from the ancestors of humans and Neanderthals between 360,000 and 1.02 million years ago.
Sure enough!
https://earthsky.org/human-world/early-humans-africa-interbred-with-extinct-species
Wow it does look very similar to the ones above....
this research suggests there were geographically diverse groups in Africa well before the main expansion out of the continent. And many of these groups will have contributed to the ancestry of people alive in Africa today.
there may also have been gene-flow into the ancestors of West Africans directly from a mysterious archaic hominin.Wow - amazing!!
6%-7% of the genomes of West Africans is archaic in origin. But this archaic ancestry wasn’t Neanderthal or Denisovan. Their model suggested the additional ancestry came from an archaic population for which we don’t currently have a genome.Holy Smokes!!
this ghost species as something akin to a Neanderthal, but that presumably was present within Africa, during the last 100,000 years. An alternative explanation is that the archaic hominin was present outside of Africa and interbred with populations there before they migrated back in.https://theconversation.com/early-humans-in-africa-may-have-interbred-with-a-mysterious-extinct-species-new-research-131699
Ancient West African foragers in the context of African population history
David Reich is solid - I think he's at Harvard...
Published in Nature - top science journal...
I'll read the whole thing
So there is a "ghost modern" - that is a split off from the "ghost archaic"
url to share this paper:
Four different lineages in Africa "diversified" - about 200,000 years ago
Newly proposed model involving introgression into the modern human ancestor from an unknown hominin that separated from the human ancestor before the split of modern humans and the ancestors of Neanderthals and Denisovans.https://advances.sciencemag.org/content/6/7/eaax5097
We examined the frequencies of archaic segments to investigate whether natural selection could have shaped the distribution of archaic alleles....
these populations derive 2 to 19% of their genetic ancestry from an archaic population that diverged before the split of Neanderthals and modern humans.
TRPS1, a gene associated with trichorhinophalangeal syndrome (71% in YRI, 75% in MSL; Table 1).
Pleiotropy (unusually tall height is from TRPS1)
none of the people at Shum Laka were closely related to Bantu speakers at all. In fact, they had a strong kinship to the Aka, a group of hunter-gatherers with a pygmy body type who live today in rain forests 1,000 miles to the east.
Dr. Reich and his colleagues can trace the major lineages of people back to common ancestors who lived in Africa between 200,000 and 250,000 years ago.
“It seems we have four lineages splitting at the same time,” said Mark Lipson, a postdoctoral researcher at Harvard and an author of the new study.
One lineage passed down their DNA to living hunter-gatherers in southern Africa. A second group were ancestors of the Aka and other central African hunter-gatherers.
A third group became hunter-gatherers in East Africa, as evidenced by the fact that many living Africans in that region have inherited some of that DN A.
https://www.nytimes.com/2020/01/22/science/ancient-dna-africa.htmlThe fourth group, which Dr. Reich and his colleagues call “Ghost Modern,” is far more mysterious.
The new research shows around 70,000 years ago, the Horn of Africa climate shifted from a wet phase called 'Green Sahara' to even drier than the region is now.https://www.sciencedaily.com/releases/2017/10/171004151231.htm
The algae change the composition of the alkenones depending on the water temperature. The ratio of the different alkenones indicates the sea surface temperature when the algae were alive and also reflects regional temperatures, Tierney said.
To figure out the region's ancient rainfall patterns from the sediment core, the researchers analyzed the ancient leaf wax that had blown into the ocean from terrestrial plants. Because plants alter the chemical composition of the wax on their leaves depending on how dry or wet the climate is, the leaf wax from the sediment core's layers provides a record of past fluctuations in rainfall.
Feb 14, 2013 - Previous genetic analyses that compared a draft sequence of the Neanderthal genome with genomes of several modern humans concluded that ...
by JD Wall - 2013 - Cited by 219 - Related articles
We find that, consistent with the recent finding of Meyer et al. (2012), Neanderthals contributed more DNA to modern East Asians than to modern Europeans.
Africans carry surprising amount of Neanderthal DNA - Science
Jan 30, 2020 - “That gene flow with Neanderthals exists in all modern humans, inside and outside of Africa, is a novel and elegant finding,” says anthropologist ...
the genomes of Yoruba people from Ibadan, Nigeria. They found more instances of genetic variation in the ancient segments than are seen in Neanderthal and Denisovan genes, suggesting that neither of these groups of ancient humans were the source of the genomic variance.
Similar patterns were seen in the genomes of Mende people in Sierra Leone, Esan people in Nigeria and those in western areas of Gambia. The four populations are estimated to derive between 2 and 19 per cent of their ancestry from an archaic group of genes.
They conclude that the ancestors of Neanderthals and Denisovans—whom they call Neandersovans—interbred with a “super-archaic” population that separated from other humans about 2 million years ago. Likely candidates include early members of our genus, such as H. erectus or one of its contemporaries. The mixing likely happened outside of Africa, because that’s where both Neanderthals and Denisovans emerged, and it could have taken place at least 600,000 years ago.
Mysterious ‘ghost’ populations had multiple trysts with human ancestors
https://www.sciencemag.org/news/2020/02/mysterious-ghost-populations-had-multiple-trysts-human-ancestors
Our new estimates do not refute this reconstruction, but they do allow a simpler one, which involves only three expansions of humans from Africa into Eurasia: an expansion of early Homo at about 1.9 Ma ago, an expansion of neandersovans at about 700 ka ago, and an expansion of modern humans at about 50 ka ago.Our results indicate that neandersovans interbred with superarchaics early in the middle Pleistocene, shortly after expanding into Eurasia. This is the earliest known admixture between hominin populations.
https://advances.sciencemag.org/content/6/8/eaay5483
We suggest that around 700 ka ago, neandersovans expanded from Africa into Eurasia, endured a bottleneck of population size, interbred with indigenous Eurasians, largely replaced them, and separated into eastern and western subpopulations—Denisovans and Neanderthals. These same events unfolded once again around 50 ka ago as modern humans expanded out of Africa and into Eurasia, largely replacing the Neanderthals and Denisovans.
The ancestor of Neanderthals and Denisovans interbred with a “superarchaic” hominin.
https://cosmosmagazine.com/palaeontology/distant-human-relative-mixed-with-our-cousins
When they interbred, the superarchaic humans and neandersovans would have been separated for 1.2 million years. The superarchaics were even more distantly related to the Denisovans they mated with.
Whether the ghost hominin from West Africa and the superarchaic hominin that Rogers and his colleagues found are one and the same is unclear, but Rogers is keen to find out.
Lurking deep in your DNA, you may have a ghostly remnant from a “super-archaic” protohuman that isn’t our ancestor [Maybe Homo Erectus]. This is because over half a million years ago, “Neandersovans” – the common ancestor of Neanderthals and Denisovans – intermixed with a small-brained, super-archaic hominin. Hundreds of thousands of years later, Denisovans did it again. And after that, Neanderthals and Denisovans intermixed with ancestors of modern humans. Got it?https://www.haaretz.com/archaeology/.premium-ghostly-genes-from-super-archaic-hominin-found-in-late-human-species-1.8560036
Theoretically, because we interbred and had fertile offspring, we’re all the same species (albeit different types). By that criterion, this 2-million-year-old demi-ape is also the same species, though whether it could have fruitfully interbred with us today is an open question.why not? here we go:
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