Out of yesterday's Neandertal ancestry-oriented papers, I am more focused on the Zlatý kůň analysis. The history of thinking about this partial skeleton and the way this paper changes that thinking has much to reveal about this moment in the science. doi.org/10.1038/s41559…
The Zlatý kůň skeleton was discovered in 1950 when a nearby limestone quarry blasted an opening into a previously unknown cave system. The skeletal remains and many artifacts were within a debris cone from a chimney going higher into the cave. doi.org/10.1007/978-1-…
From the beginning, it was unclear whether the skeleton and artifacts were associated. All appeared to have entered accidentally, falling from chambers above. This was not an occupation site. The human remains emerged over several excavation seasons.
Svoboda, who summarized the context in a 2000 review, was very skeptical about the (few) artifacts: "Traditionally, rather than on the basis of any typological data, archaeologists ascribe these finds to the Early Upper Paleolithic." doi.org/10.1006/jhev.1…
Basically, anthropologists prior to 2000 who worked on Upper Paleolithic material from Central Europe thought Zlatý kůň was very comparable in anatomy to Mladeč, a very early site, and placed it within the sample of earliest Upper Paleolithic skeletal remains.
Some suggested its occipital morphology might reflect Neandertal ancestry, and noted that its cranial morphology is relatively robust for a female adult individual, resembling other skeletal remains from this early Upper Paleolithic sample.
In the late 1990s, the scientific scene shifted a bit. A new generation of scientists was starting to question these legacy sites from decades earlier, particularly in central Europe, using new radiocarbon approaches and other methods.
A frontal bone from Hahnöfersand, Germany, once thought to be early Upper Paleolithic and a possible Neandertal hybrid, turned out to be only 5400 years old. A frontal fragment from Velika Pećina, Croatia, was Neolithic, not early UP.
Human remains from Vogelherd cave, Germany, were thought to be Aurignacian in age, turned out to be Neolithic also. Zlatý kůň was part of this redating regime, and Svoboda and coworkers in 2002 found a date: 12,870±70 years. They argued it was Magdalenian. doi.org/10.1017/S00035…
In their paper describing the date, they wrote: "The region of the Bohemian karst has a predominantly Magdalenian occupation. No significant Early Upper Paleolithic site has been proved before in the vicinity."
I'm going to some effort on this background because the redating wave at the turn of the century looked to many observers like science triumphing over cloudy-headed thinking. The past was not what anthropologists had thought! This was, of course, true to some degree. Yet...
...today we get a sense of the overreach. The Zlatý kůň woman did not live 12,000 years ago; the radiocarbon assessment in 2002 was wrong, glue has contaminated the collagen content, and she lived at least 36,000 years ago and probably longer.
The DNA confirms some of what anthropologists thought 25 years ago, and adds the new resolution about a higher degree of Neandertal ancestry than today's Europeans, with some Neandertal input within 70-80 generations of her birth. doi.org/10.1038/s41559…
Also worth noting is the partial Neandertal ancestry in a chromosome 1 region that currently stands out as an "introgression desert" -- the Neandertal ancestry hung around for some time in this region, compatible with drift or weak selection, not hybrid incompatibility.
It is probably no surprise to anybody that the current research doesn't address the history going back to 1950 and ideas about where this skull fits into human relationships. This ancient woman has long mattered in the way that scientists constructed human identity.
The two papers on Zlatý kůň and Bacho Kiro together presage a new shift in construction of early Upper Paleolithic identity. Their DNA seems to have made little difference to later populations in the European region, seems to reflect deeper and more eastern roots and relations.
In this shift, we should be wary of overreach. These populations were a complex network. It will be amazing to find cultural connections with initial Upper Paleolithic in central Asia, at places like Kara-Bom. But biological connections may record a broader range of interactions
Today we are only scratching the surface of what the data hold, and simplifying to "closest" relationships, or quantifying relative Neandertal ancestry fractions, is not telling very much of the story that awaits us.
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A hint of the social behavior of early Homo erectus comes from the earliest known #hominin to survive with near total loss of teeth, 1.8 million years ago. Some wild primates also survive years with little functional dentition. #paleoanthropology#FossilFriday
For years, anthropologists have looked at the survival of older people with tooth loss as a possible indication of social caring, empathy, and value of tradition and knowledge to social groups—once with Neandertals, more recently with H. erectus. #paleoanthropology
Some have criticized inferences about social care in these human relatives, by pointing out other primates that sometimes survive. This wild chimpanzee skull in the collection of the @goCMNH is a great example, with loss of all but one molar and premolars.
The MH2 #hominin mandible is still being built, fragment by fragment, as pieces are recovered from Malapa and prepared in the lab. The skull of this adult Australopithecus sediba individual may be found within the breccia as well. #paleoanthropology
If you're following this series of illustrations, you may recognize that MH2 is my first repeat, as I earlier featured the MH2 pelvis. The Malapa skeletons are amazing examples of discovery, as each piece emerges from the site, it allows us to test new hypotheses.
Some scientists claimed that the difference between MH1 and MH2 mandibular ramus shape must mean that one is Australopithecus and one Homo. Ritzman and coworkers (2016) examined this, finding them compatible with normal within-species variation. dx.doi.org/10.1016/j.jhev…
Some say MSA/Middle Paleolithic hominins used ochre for sun protection, blocking any conclusions about marking or other symbolic uses. I say traditions of processing and using mineral pigments for sun protection are more complex and less universal than cosmetic uses.
Some archaeologists have focused on cosmetic uses of pigments, but it remains much more common to see ochre and other pigments framed in terms of "symbolic marking" or "marking".
Of course, cosmetics are used for symbolic marking, and also other kinds of marking, and much use of cosmetics across cultures is directed toward mimicry, enhancing the visual impact of features, or reducing the visual impact of features, not "symbolic" in a strict sense.
So, I've started tracking down the citations in this Magnetodeth paper. It will be a surprise to no one that the papers on genetic bottlenecks do not support the 42,000-year-ago event that the new paper says they do.
For example, the paper claims that thylacines underwent a bottleneck 42,000 years ago, citing Lauren White et al. 2018 doi.org/10.1111/jbi.13… That paper actually says 20,400 years.
In the Australian case, the cited papers note that extinctions had a regional pattern that began by 48,000 years ago, the number 42,000 refers to a particular Bayesian analysis and not actual last appearance dates (which are more dispersed) doi.org/10.1038/s41467…
One way of casting this lack of knowledge is to say maybe there was no "origin", that we are looking backward through a cloudy lens at a gradual mixing process that never had a beginning. This idea comports with what we know about continued Neandertal-African mixing.
Yet with Neandertals we intently focus on mechanism: "How much mixing happened, on how many occasions, and how much did it matter?" Surely this must factor into the way we look at evolution within Middle Pleistocene Africa also. With more data, we will focus on those questions.
Lactase persistence and dairying on the surface seem to be a simple and compelling example of gene-culture coevolution in humans. And yet there are patterns that confound the simplistic story. I appreciate that @Maddy_Bleasdale et al discuss some of those. nature.com/articles/s4146…
Several aspects of lactase persistence genetics are not being covered well by press accounts of this paper. Journalists have gone with a pretty simple "counterintuitive lede", i.e., people were drinking milk before lactase persistence mutations were common.
A look at the great frequency maps in the paper is enough to remind folks of the reality that most lactase persistence-associated alleles *still* aren't very common. They have frequency maxima of 2-5% today and are highly localized.