quote:Originally posted by BrandonP: There is of course the recent argument that H. sapiens may be a "composite" species that came about after populations from different regions of the continent intermixed. Some people have taken to calling it "African multiregionalism":
Unfortunately most of the article is behind a paywall, but the caption summarizes it thus:
quote:Several new discoveries suggest that our species didn’t arise from a single point in space. Instead, the entire continent was our cradle.
Indeed I've always questioned how anyone-- geneticist or paleo-anthropologist-- could pinpoint an exact area or locality in Africa where the species originated.
Here is the 2018 study that a lot of this is based on: 'Did Our Species Evolve in Subdivided Populations across Africa, and Why Does It Matter?' [I couldn't post the url link but it's an issue of cell.com]
The study suggests that there were periods of isolation between various populations (bottleneck events) followed by periods of extensive geneflow. The former caused by arid conditions while the latter wet conditions. Thus pinpointing an exact area in Africa as the one specific spot where the species arose is virtually impossible. Indeed, there is the suggestion that Sapiens could have been the result of various subspecies comingling through the process I just outlined.
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The same year the above study was published Scientific American wrote an article on it which I happen to grab an issue of.
The Last Hominin Standing: Why Did Homo Sapiens Alone Survive to the Modern Era? By Kate Wong At the dawning of Homo sapiens, our ancestors were born into a world we would find utterly surreal. It’s not so much that the climate and sea levels or the plants and the animals were different, although of course they were—it’s that there were other kinds of humans alive at the same time. For most of H. sapiens’ existence, in fact, multiple human species walked the earth. In Africa, where our species got its start, large-brained Homo heidelbergensis and small-brained Homo naledi also roamed. In Asia, there was Homo erectus, a mysterious group dubbed the Denisovans and, later, Homo floresiensis—a hobbitlike creature, tiny but for its large feet. The stocky, heavy-browed Neanderthals, for their part, ruled Europe and western Asia. And there were probably even more forms, as yet undiscovered. By around 40,000 years ago, based on current evidence, H. sapiens found itself all alone, the only remaining member of what was once an incredibly diverse family of bipedal primates, together known as hominins. (In this article, the terms “human” and “hominin” both refer to H. sapiens and its extinct relatives.) How did our kind come to be the last human standing? Until a few years ago, scientists favored a simple explanation: H. sapiens arose relatively recently, in more or less its current form, in a single region of Africa and spread out from there into the rest of the Old World, supplanting the Neanderthals and other archaic human species it encountered along the way. There was no appreciable interspecies fraternizing, just wholesale replacement of the old guards by the cleverer newcomer, whose ascendancy seemed inevitable. Yet mounting evidence from fossil and archaeological discoveries, as well as DNA analyses, has experts increasingly rethinking that scenario. It now looks as though H. Sapiens originated far earlier than previously thought, possibly in locations across Africa instead of a single region, and that some of its distinguishing traits—including aspects of the brain—evolved piecemeal. Moreover, it has become abundantly clear that H. sapiens actually did mingle with other human species it encountered and that interbreeding with them may have been a crucial factor in our success. Together these findings paint a far more complex picture of our origins than many researchers had envisioned—one that privileges the role of dumb luck over destiny in the success of our kind.
THEORY UNDER THREAT Debate about the origin of our species has traditionally focused on two competing models. One one side was the Recent African Origin hypothesis, championed by paleoanthropologist Christopher Stringer and others, which argues that H. sapiens arose in either eastern or southern Africa within the past 200,000 years and, because of its inherent superiority, subsequently replaced archaic hominin species around the globe without interbreeding with them to any significant degree. On the other was the Mulitregional Evolution model, formulated by paleoanthropologists Milford Wolpoff, Xinzhi Wu and Alan Thorne, which holds that modern H. sapiens evolved from Neandertals and other archaic human populations throughout the Old World, which were connected through migration and mating. In this view, H. sapiens has far deeper roots, reaching back nearly two million years. By the early 2000s the Recent African Origin model had a wealth of evidence in its favor. Analyses of the DNA of living people indicated that our species originated no more than 200,000 years ago. The earliest known fossils attributed to our species came from two sites in Ethiopia, Omo and Herto, dated to around 195,000 and 160,000 years ago, respectively. And sequences of mitochondrial DNA (the tiny loop of genetic material found in the cell’ power plants, which is different from the DNA contained in the cell’s nucleus) recovered from Neandertal fossils were distinct from the mitochondrial DNA of people today—exactly from the mitochondrial DNA of people—exactly as one would expect if H. sapiens replaced archaic human species without mating with them. Not all of the evidence fit with this tidy story, however. Many archaeologists think that the start of a cultural phase known as the Middle Stone Age (MSA) heralded the emergence of people who were beginning to think like us. Prior to this technological shift, archaic human species throughout the Old World made pretty much the same kinds of stone tools fashioned in the so-called Acheulean style. Acheulean technology centered on the production of hefty hand axes that were made by taking a chunk of stone and chipping away at it until it made the desired shape. With the onset of the MSA, our ancestors adopted a new approach to toolmaking, nverting the knapping process to focus on the small, sharp flakes they detached from the core—a more efficient use of raw material that required sophisticated planning. And they began attaching these sharp flakes to handles to create spears and other projectile weapons. Moreover, some people who made MSA tools also made items associated with symbolic behavior, including shell beads for jewelry and pigment for painting. A reliance on symbolic behavior, including language, is thought to be one of the hallmarks of the modern mind. The problem was that the earliest dates for the MSA were more than 250,000 years ago—far older than those of the earliest H. sapiens fossils at less than 200,000 years ago. Did another human species invent the MSA, or did H. sapiens actually evolve far earlier than the fossils seem to indicate? In 2010 another wrinkle emerged. Geneticists announced that they had recovered nuclear DNA from Neandertal fossils and sequenced it. Nuclear DNA makes up the bulk of our genetic material. Comparison of the Neandertal nuclear DNA with that of living people revealed that non-African people today carry DNA from Neandertals, showing that H. sapiens and Neandertals did interbreed after all, at least on occasion. Subsequent ancient genome studies confirmed that Neandertals contributed to the modern human gene pool, as did other archaic humans. Further, contrary to the notion that H. sapiens originated within the past 200,000 years, the ancient DNA suggested that Neandertals and H. sapiens diverged from their common ancestor considerably earlier than that, perhaps upward of half a million years ago. If so, H. sapiens might have originated more than twice as long ago as the fossil record indicated.
ANCIENT ROOTS Recent discoveries at a site called Jebel Irhoud in Morocco have helped bring the fossil, cultural, and genetic evidence into better alignment—and bolstered a new view of our origins. When barite miners first discovered fossils at the site back in 1961, anthropologists thought the bones were around 40,000 eyars old and belonged to Neandertals. But over the years continued excavations and analyses led researchers to revise that assessment. In June 2017 paleoanthropologist Jean-Jacque Hublin of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and his colleagues announced that they had recovered additional fossils form the site, along with MSA tools. Using two dating techniques, they estimated the remains to be roughly 315,000 years old. The researchers had found the oldest traces of H. sapiens ot date, as well as the oldest traces of MSA culture—pushing back the fossil evidence of our species by more than 100,000 years and linking it to the earliest known appearance fo the MSA. Not everyone agrees that the Jebel Irhoud fossils belong to H. sapiens. Some experts think they may instead come from a close relative. But if Hublin and his collaborators are right about the identity of the bones, the constellation of skull straits that distinguish H. sapiens from other human species did not all emerge in lockstep at the inception of our kind, as supporters of the Recent African Origin theory had supposed. The fossils resemble modern humans in having a small face, for example. But the braincase is elongated like those of archaic human species rather than rounded like our own dome. This shape difference reflects difference in brain organization: compared with fully modern humans, the Jebel Irhoud individuals had smaller parietal lobes, which process sensory input, and a smaller cerebellum, which is involved in language and social cognition, among other functions. Neither do the archaeological remains at Jebel Irhoud exhibit the full complement of MSA features. The people there made MSA stone tools for hunting and butchering gazelles that roamed the grasslands that once carpeted this now desert landscape. And they built fires, probably to cook their food and warm themselves against the chill of night. But they did not leave behind any traces of symbolic expression. IN fact, on the whole, they are not especially more sophisticated than the Neandertals fo H. heidelbergensis. If you could journey back in time to our species’ debut, you wouldn’t necessarily pick it to win the evolutionary sweepstakes. Although early H. sapiens had some innovations, “there weren’t any big changes at 300,000 years ago that indicate they were destined to be successful,” observes archaeologists Michael Petraglia of the Max Planck Institute for the Science of Human History in Jena, Germany. “In the beginning with sapiens,” Petraglia says, “it looks like anyone’s game.”
GARDENS OF EDEN The total H. Sapiens package, many researchers agree, did not coalesce until sometime between 100,000 and 40,000 years ago. So what happened in the intervening 200,000 years or more to transform our species from run-of-the-mill hominin to world-conquering force of nature? Scientists are increasingly thinking about how the size and structure of the early H. sapiens population might have factored into the metamorphosis. In a paper published online in 2018 in Trends in Ecology & Evolution, archaeologist Eleanor Scerri of the University of Oxford and a large interdisciplinary group of co-authors, including Stringer, make the case for what they call the African Multiregionalism model of H. sapiens evolution. The scientists note that the earliest putative members of our species—namely, the Jebel Irhoud fossils from Morocco, the Herto and Omo Kibish fossils from Ethiopia, and a partial skull from Florisbad, South Africa—all look far more different from one another than people today do. So they belong to different species or subspecies. “But maybe early H. sapiens was just ridiculously diverse,” Scerri offers. And maybe looking for a single point of origin for our species, as many researchers have been doing is “a wild goose chase,” she says. When Scerri and her colleagues examined the latest data from fossils, DNA and archaeology, the emergence of H. sapiens began to look less like a single origin story and more like a pan-African phenomenon. Rather than evolving as a small population in a particular region of Africa, they propose, our species emerged from a large population that was subdivided into different groups distributed across the vast African continent that were often semi-isolated for thousands of years at a time by distance and by ecological barriers such as deserts. Those bouts of solitude allowed each group to develop its own biological and technological adaptations to its own niche, be it an arid woodland, or a savanna grassland, a tropical rain forest, or a maritime coast. Every so often, however, the groups came into contact with one another, allowing for both genetic and cultural exchange that fed the evolution of our lineage. Shifting climate could have fueled the fracturing and rejoining of the subpopulations. For instance, paleoenvironmental data have shown that every 100,000 years or so, Africa enters into a humid phase that transforms the Sahara Desert into a lush expanse of vegetation and lakes. These Green Sahara episodes, as they are known, would have allowed populations formerly isolated by the harsh desert to link up. When the Sahara dried out again, populations would be sequestered anew and able to undergo their own evolutionary experiments for another stretch of time until the next greening. A population subdivided into groups that each adapted to their own ecological niche, even as occasional migration between groups kept them connected, would explain not only the mosaic evolution of H. sapiens’ distinctive anatomy but also the patchwork pattern of the MSA, Scerri and her co-authors argue. Unlike Acheulean tools, which look mostly the same everywhere they turn up throughout the Old World, MSA tools exhibit considerable regional variation. Sites spanning the time between 130,000 and 60,000 years ago in North Africa, for example, certain tool types not found at sites in South Africa from the same interval, including stone implements bearing distinctive stems that may have served as attachment points for handles. Likewise, South African sites contain slender, leaf-shaped tools made of stone that was heated to improve its fracture mechanics—no such implements appear in the North African record. Complex technology and symbolism become more common over time across the continent, but each group acts its own way, tailoring its culture to its specific niche and customs. H sapiens was not the only hominin evolving bigger brains and sophisticated behaviors, however. Hublin notes that human fossils from China dating between 300,000 and 50,000 years ago, which he suspects belong to Denisovans, exhibit increased brain size. And Neandertals invented complex tools, as well as their own forms of symbolic expressions and social connectedness, over the course of their long reign. But such behaviors do not appear to have become as highly developed or as integral to their way of life as they eventually did in ours, observes archaeologist John Shea of Stony Brook University, who thinks that advanced language skills allowed H. sapiens to prevail. “All these groups are evolving in the same direction,” Hublin says. “But our species crosses a threshold before the others in terms of cognitive ability, social complexity, and reproductive success,” And when it does—around 50,000 years ago, in Hublin’s estimation—“the boiling milk escapes the saucepan.” Forged and honed in Africa, H. sapiens could now enter virtually any environment on the earth and thrive. It was unstoppable.
CLOSE ENCOUNTERS Hundreds of thousands of years of splitting up from and reuniting with members of our own species might have given H. sapiens an edge over other members of the human family. But it was not the only factor in our rise to world domination. We may actually owe our extinct relatives a substantial debt of gratitude for their contributions to our success. The archaic human species that H. sapiens met as it migrated within Africa and beyond its borders were not merely competitors—they were also mates. The proof lies in the DNA of people today: Neandertal DNA makes up some 2 percent of the genomes of Eurasians; Denisovan DNA composes up to 5 percent of the DNA of Melanesians. And a recent study by Arun Durvasula and Siriam Sankararaman, both at the University of California, Los Angeles, found that nearly 8 percent of the genetic ancestry of the West African Yoruba population traces back to an unknown archaic species. Other genetic evidence from contemporary populations suggests that H. sapiens also interbred with unknown extinct hominins in South and East Asia. Some of the DNA that H. sapiens picked up from archaic hominins may have helped our species adapt to the novel habitats it entered on its march across the globe. When geneticist Joshua Akey of Princeton University and his colleagues studied the Neandertal sequences in modern human populations, they found 15 that occur at high frequencies, a sign that they had beneficial consequences. These high-frequency sequences cluster into two groups. About half of them influence immunity. “As modern humans dispersed into new environments, they were exposed to new pathogens and viruses,” Akey says. Through interbreeding, “they could have picked up adaptations from Neandertals that were better to fight off those new pathogens,” he explains. The other half of the Neandertal sequences that Akey’s team found at high frequency in modern human populations are related to skin, including genes that influence pigmentation levels. Researchers have previously theorized that H sapiens individuals from Africa, who presumably had darker skin to protect against harmful ultraviolet radiation from the sun, would have had to evolve lighter skin as they entered northern latitudes to get enough vitamin D, which the body acquires mainly through sun exposure. Skin genes from Neandertals may have aided our predecessors in doing exactly that. Neandertals are not the only archaic humans who gave us useful genes. For example, modern –day Tibetans have the Denisovans to thank for a gene variant that helps them cope with the low-oxygen environment of the high-altitude Tibetan plateau. And contemporary African populations have inherited from an unknown archaic ancestor a variant of a gene that may fend off bad bacteria inside the mouth. Interbreeding with archaic humans who had millennia to evolve adaptations to local conditions may well have allowed invading H. sapiens to adjust to novel environments faster than if it had to wait for favorable mutations to crop up in its own gene pool. But it’s not all upside. Some of the genes we obtained from Neandertals are associated with depression and other diseases. Perhaps these genes were advantageous in the past and only began causing trouble in the context of modern ways of life. Of maybe, Akey suggests, the risk of developing these diseases was a tolerable price to pay for the benefits these genes conferred. Archaic humans may have contributed more than DNA to our species. Researchers have argued that contact between divergent human groups probably led to cultural exchange and may have even spurred innovation. For example, the arrival of H. sapiens in western Europe, where the Neandertals long resided, coincided with an uncharacteristic burst of technological and artistic creativity in both groups. Previously some experts suggested that Neandertals were simply aping the inventive newcomers. But maybe it was the interaction between the two groups that ignited the cultural explosion on both sides. In a sense, the fact that H. sapiens mixed with other human lineages should not come as a surprise. “We know from many animals that hybridization has played an important role in evolution,” observes biological anthropologist Rebecca Rogers Ackermann of the University of Cape Town in South Africa. “In some cases, it can create populations, and even new species, that are better adapted to new of changing environments than their parents were because of novel traits or novel combinations of traits.” Human ancestors show a similar pattern: the combination of different lineages resulted in the adaptable, variable species we are today. “Homo Sapiens is the product of a complex interplay of lineages,” Ackermann asserts, and it has flourished precisely because of the variation that arose from this interplay. “Without it,” she says, “we simply wouldn’t be as successful.” How often such mingling occurred and the extent to which it helped drive evolution in H. sapiens and other hominins remain to be determined. But it may be that the particular environmental and demographic circumstances in which our species found itself in Africa and abroad led to more opportunities for genetic and cultural exchange with other groups than our fellow hominins experienced. We got lucky—and are no less marvelous for it.
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^ The biggest division between Africans is between Aboriginal Southern Africans (Khoisan) and all other Africans.
This is why even Sub-Saharan West Africans (IBD populations) are closer related to West Eurasians than they are to Khoisan. As Loosdrecht et al. illustrated.
Another interesting fact is that the Khoisan folk are themselves genetically divided into two main groups as illustrated in Schlebusch's cladogram and was noted years ago.
Two studies exploring the genetics of hunter-gatherers and pastoralists in sub-Saharan Africa, where humans are thought to have originated, reveal that even though the click-language peoples of southern Africa live in close proximity, they belong to two distinct genetic clusters.
To assess the degree of genetic difference, both teams looked at single nucleotide polymorphisms (SNPs) — variations at individual nucleotides between different people — in the DNA of the various populations. One study, led by Carina Schlebusch at Uppsala University in Sweden and published today in Science1, analysed SNPs from 220 individuals belonging to 11 different southern African populations. The other, led by Joseph Pickrell at Harvard Medical School in Boston, Massachusetts, and posted to the arXiv preprint server ahead of its publication in Nature Communications2, examined SNPs from 187 individuals belonging to 23 southern and eastern African populations.
By considering the similarities and differences among the SNPs in the various click-speaking peoples, and comparing them with patterns from other African populations, the teams were able to identify ancestral relationships. Both teams deduced that the southern African click-speaking populations (known generally as the Khoisan) actually belong to two genetically differentiated groups, one in the north and and one in the south of the Kalahari, which went their separate ways around 30,000 years ago. The discovery of this genetic divide is raising numerous questions about how it could have come about.
“It makes you wonder if they became isolated from one another for cultural reasons, or if there was some sort of geographical isolation that led to the differentiation,” says Sarah Tishkoff, a human-origins geneticist at the University of Pennsylvania in Philadelphia.
Evolutionary geneticist Rasmus Nielsen at the University of California, Berkeley, agrees with the idea of the environment being involved. “Africa was very dry during the last glacial maximum, and this might have led to an extended period of smaller overall population sizes, more population subdivision and increased fragmentation,” he says.
East meets south
Aside from identifying a key time of separation among southern African peoples, Pickrell and his colleagues also discovered an ancient genetic relationship between the south and east of the continent. They found that the Sandawe and the Hadza, east-African hunter-gatherers who speak a click language but are geographically isolated from the other Khoisan peoples, derive roughly a quarter of their ancestry from the southern African click-speakers. This, Pickrell argues, implies the existence of a link having once existed between these peoples.
The possibility of such a connection is important because tensions have been growing among anthropologists as fossil evidence unearthed by palaeontologists increasingly suggests that modern humans originated in east Africa whereas genetic studies have suggested a southern origin. The identification of a genetic link between south and east Africa may help to resolve this conundrum.
Southern selection
Schlebusch and her colleagues also noticed that some of the genes in the populations they were studying seem to have undergone changes due to natural selection since the two southern-African groups split 30,000 years ago. They included genes involved in muscle function and growth and, intriguingly, genes involved in immunity.
The reasearchers found that the more southerly of the two groups carry evidence for selected changes in two immune-related genes, whereas these genes in the more northerly group show no signs of selection.
“This signal could be due to this population having early and extensive contact with European colonists and suffering epidemics such as smallpox,” explains Schlebusch.
Tishkoff says that this again raises the question of “whether these populations were once geographically widespread and experienced local adaptation to different environments”.
And as I've shown before, the dental nonmetrics very highly reflects genetics.
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quote:But such behaviors do not appear to have become as highly developed or as integral to their way of life as they eventually did in ours, observes archaeologist John Shea of Stony Brook University, who thinks that advanced language skills allowed H. sapiens to prevail. “All these groups are evolving in the same direction,” Hublin says. “But our species crosses a threshold before the others in terms of cognitive ability, social complexity, and reproductive success,” And when it does—around 50,000 years ago, in Hublin’s estimation—“the boiling milk escapes the saucepan.” Forged and honed in Africa, H. sapiens could now enter virtually any environment on the earth and thrive. It was unstoppable.
I think this argument that advanced language capabilities and their ramifications distinguished modern humans (as in Late Stone Age/Upper Paleolithic descendants) from other hominins makes sense. I will have to dig it up later when I get home, but Chris Ehret has pointed out that even supposed AMH living in Israel over 100 kya would have had a vocal tract different enough from modern humans to have limited their linguistic capabilities. I do think 50 kya is a bit too recent to have been the origin point for LSA/UP humans though.
quote: Demographic model of African history and estimated divergences. (a) Population split times, hierarchy, and population sizes (summarized from 123). Horizontal width represents population size; horizontal colored lines represent migrations, with down-pointing triangles indicating admixture into another group. (b) Population structure analysis at 5 assumed ancestries (K=5) for 93 African and 6 non-African populations. Non-Africans (brown), East Africans (blue), West Africans (green), central African hunter–gatherers (light blue), and Khoe-San (red) populations are sorted according to their broad historical distributions. Data were obtained from several studies (4, 16, 44, 53, 70, 89, 125), and the details of the analysis are described in the Supplemental Methods . Abbreviation: BP, years before present.
Figure 3
quote:
Population structure analysis and inferred ancestry components for selected choices of assumed number of ancestries (K=3, 6, 9, and 11) for 93 African and 6 non-African populations. Figure 2 displays the ancestry components for K=5. The broad geographical distributions are indicated on the left. The columns on the right indicate ethnic affiliation, country of origin, language family, and language subfamily. Data were obtained from several studies (4, 16, 44, 53, 70, 89, 125), and the details of the analysis are described in the Supplemental Methods . Abbreviations: CAR, Central African Republic; DRC, Democratic Republic of the Congo.
Interesting. I don't think i seen these before. Not to change the topic to much but i have to say however like i mention in another thread the mandinka term could be/is misleading because when folks think of mandinka at times they think of those of mali and guinea for example and that study above is really talking about the mandenka mandinka from gambia and not the maninka mandinka of mali and guinea.
When they use mandinka for the above i knew it was really gambia or senegal or both for these studies. Of course the above is talking only gambia.
The joshuaproject does not even list the maninka as mandinka in the People Name General/People Name in Country section. Note- but they do list mandinka has one of the alternate Names.
Alternate Names Konyanke; Mandingo; Mandinka; South Maninka; Wangara
This reminds me when folks get confused when nubian is talked about from sudan and egypt for example vs nubian from kenya because those nubians from kenya are not really nubians,they are nubi.
Then there is sudanese nuba vs nubian. Of course some nuba are really nubians(hill nubians) Then there is kushite vs cushite. One was a ethnic group and the other is a language group. Ancient ethiopia(sudan) vs ethiopia when the greeks were talking about ethiopia it was really kush/sudan.
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^ Thanks for the clarification on the Mandinka. I didn't know about the Senegambian Mandinka. I guess it's similar to how the agricultural Fulani of coastal Guinea are confused with the pastoral Fulani of the Sahel. I also had no clue about the Kenyan Nubians. This is why specificity is important in regards to population sampling.
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Many people forget that there was child found in the same site as Herto Man. Swenet and I discussed it here, but due to the relevance of this thread. I'll repost it below:
quote:Originally posted by Swenet: Must have been a rare report then, because there is almost no discussion on this child in the literature. Almost everything in the literature focuses on the adult Herto male. As a result the photographs of child's remains are far more difficult to find than the photographs of the adult male, even though both photographs come from the same paper. This is what it was like when I looked into this years ago. Situation might have improved in google, but I doubt it, because I know why it's like this in the first place.
I'm trying to find the paper I read years back when I was in high school, but I can only find recent papers like these:
African paleoanthropology has long been influenced by eurocentricframes of reference in geology, paleontology, and archaeology. Indeed, the “Middle Stone Age” of Africa is often equated with the “Middle Pale-olithic” as defined and manifested in Europe. Even the ill-defined “Homo heidelbergensis” is still applied to African fossils. More broadly, notions that technological “cultures” arose unilineally via “transitions” persist among Paleolithic archaeologists. On the other hand, and ironically, the strict application of cladistic classification disallows nomenclatural recognition of phyletic evolution along evolving species lineages. Combined with an under-appreciation of intraspecific skeletal variation, the approach has produced species inflation and a consequently confusing jungle of phylogenetic diagrams and labels applied to hominid fossils of all antiquities (White 2009, 2014). Scerri et al. represent a recent manifestation of this when they write of “...morphologically varied populations pertaining to the H. sapiens clade” living “throughout Africa”(2018: 582). Left unspecified is what they mean by “pertaining to.” The inability of rigid biological classificatory labels to adequately express dynamic change continues to plague the depiction and under-standing of how our species lineage evolved through the Middle Pleistocene. However convenient static Linnean labels may be to claims about the “earliest” whatever taxon, such labels often work in opposition to expressing and understanding the mode and tempo of evolutionary change (White 2000, 2009, 2014).
For example, in biological anthropology a classificatory scheme based exclusively on branching speciation (cladistic classification, see below) would identify Homo sapiens based on an inferred “Homo sapiens clade” that reaches back >500,000 years ago, to a point at which African (Homo sapiens) and European (Homo neanderthalensis) biological species lineages diverged (apparently with minor subsequent introgression between them). In this scheme, anatomies as disparate as Bodo and Herto must both be classified cladistically as Homo sapiens.
Others adopt an anatomical approach, classifying as Homo sapiens only those fossils that display a specific suite of derived anatomical characters shared exclusively with anatomically modern humans. We prefer the latter approach, and nomenclaturally recognize those fossils (such as Bodo) interpreted to be the direct lineal ancestors of Homo sapiens as different chrono species, pending finer resolution of the paleontological record.
quote:Originally posted by Swenet: ^Did you notice that your paper has the Herto boy with recent humans, while the Herto adult is with so-called 'archaics'? That's exactly the evidence I wanted to see confirmed (see my second post where I said I'm waiting for clarification).
Yes! His juvenile morphometric pattern is similar to contemporary Sapiens juveniles. I was trying to find another study that came out right after the Herto discovery saying how because it's a child it is uncertain due to paedomorphic features showing similarity between different species of a genus or even family.
quote:Will have to go over it closely, to make sure I get everything from it. I also want to see if they elaborate on this massive morphological distance between these two Herto fossils and the fact that this means that adult Herto isn't in our lineage, at all. (imagine if Oase I is not ancestral to later Europeans/Eurasians, how far removed Herto must be given how similar he looks to the photographs of Kabwe in the 2003 White et al paper. [In the White et al paper the Herto adult, to me, looks like a cross/hybrid between the photographs of Qafzeh 9 and Kabwe, while Herto boy looks like neither and closer to us living humans]).
Yes, I have read that because of Herto's features he was deemed to probably come from a different line or subspecies of Sapiens hence his name Homo sapiens idaltu as opposed to Homo sapiens sapiens. However, I personally hesitate to make any conclusions without say conclusive genetic evidence. Recall the Zhoukoudian Upper Cave Series. All three skulls are contemporary to each other yet all three look very different from each other as to suggest different population origins yet the late Dr. Christy Turner and others have shown that all three skulls possess sinodont teeth. If there was that much craniometric variation among early East Asians at that time there is no telling what kind of variation existed in Africa that far back. If according to Turner the UC Zhoukoudian skulls belong to the same population despite their difference in facial features, who's to say that Herto Man and Child don't belong to the same family??!
quote:Originally posted by Swenet:
quote:Originally posted by Djehuti: Yes, I have read that because of Herto's features he was deemed to probably come from a different line or subspecies of Sapiens hence his name Homo sapiens idaltu as opposed to Homo sapiens sapiens. However, I personally hesitate to make any conclusions without say conclusive genetic evidence. Recall the Zhoukoudian Upper Cave Series. All three skulls are contemporary to each other yet all three look very different from each other as to suggest different population origins yet the late Dr. Christy Turner and others have shown that all three skulls are possess sinodont teeth. If there was that much craniometric variation among early East Asians at that time there is no telling what kind of variation existed in Africa that far back. If according to Turner the UC Zhoukoudian skulls belong to the same population despite their difference in facial features, who's to say that Herto Man and Child don't belong to the same family??!
Upper Palaeolithic sapiens skeletal remains at the same site often seem to belong to different 'races', either races we can recognize today (e.g. so-called 'Australoid' fossils), or they show variation large enough to be consistent with different races. You've mentioned the Upper Cave skeletal remains, and we also see it at Herto, Kostenki, Cro Magnon, Predmost, Qafzeh/Skhul, among other examples. Then there is the related finding that individual fossils separated by distance can have more of a resemblance than individuals at the same site. An example of this is Upper Cave 101 having its closest match in Ohalo I from the Levant, as opposed to anything at the Upper Cave site or the rest of China. Or you can have something like Mladec I showing more of a resemblance to Cro Magnon I than either does to Mladec II. Only at the latest phase of the Upper Palaeolithic we begin to see large samples that are homogeneous in a sense, in that they have a population affinity that is found more or less consistently throughout the population (e.g. Taforalt and Afalou, Jebel Sahaba, pre-Mesolithic al Khiday).
Scientists have never been able to explain this and I find it telling that some palaeontologists are going so far as to circulate new fossils amongst themselves before publishing so as to not get caught off guard by new fossils. You can't have it both ways. Either you're an expert and your predictions work and you're deserving of the trust the public vests in you, or you're not and you're losing control of the narrative with all these so-called archaics being found that don't match their predictions of human origins.
Posts: 26516 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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quote:Originally posted by Djehuti: ^ Thanks for the clarification on the Mandinka. I didn't know about the Senegambian Mandinka. I guess it's similar to how the agricultural Fulani of coastal Guinea are confused with the pastoral Fulani of the Sahel. I also had no clue about the Kenyan Nubians. This is why specificity is important in regards to population sampling.
Yes and here is some talk about that.
Gambian in Western Division – Mandinka [GWD]
quote: Population Description
These cell lines and DNA samples were prepared from blood samples collected from people living in the Western District of Gambia from individuals who identified themselves as Mandinka. All parents in the trios identified themselves as having Mandinka parents of at least two generations.
Referring to Populations It is important to refer to this community as “Gambian in Western Division – Mandinka” when describing these samples in articles or presentations. Including the full name reinforces the point that the sample set does not represent all Mandinka people or all Gambian people, whose population history is complex. The population should not be described merely as “African”, “Sub-Saharan African”, “West African”, or “Gambian”, since each of those designators encompasses many communities.
The full population descriptor is Gambian in Western Division – Mandinka and the abbreviation is GWD.
Additional guidance about how to refer to the populations can be found at Guidelines for Referring to the Populations in Publications and Presentations.
Here are some population codes use in dna studies.
GF1 Fula I in Gambia
GF2 Fula II in Gambia
GMD Mandinka II in Gambia
GNA Akans in Ghana
GSR Serere in Gambia
GWD Gambian in Western Division, Mandinka
GWL Wollof in Gambia
MLB Bambara in Mali
MLM Malinke in Mali
MSL Mende in Sierra Leone
YRI Yoruba in Ibadan, Nigeria
quote: Map of Africa. The approximate location of 40 populations typed for Y chromosome markers in this study (•) and 39 populations surveyed for HVS1 sequence data12, 31, 32, 33 (○) are indicated. The distribution of the four African language families was constructed using Greenberg's39 classifications and further refined with data from the ethnologue (http://www.ethnologue.com/). Three shades of gray on map refer to the distribution of language families: Khoisan (light gray, southwest), Afroasiatic (light gray, north), Niger-Congo (medium gray), and Nilo-Saharan (dark gray). The circled geographic regions include North, West, Central, East, and South Africa.
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