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‘Dragon Man’ may be an elusive Denisovan (science.sciencemag.org)
76 points by etiam on July 2, 2021 | hide | past | favorite | 48 comments



It may also not be a new species. And a lot of pop science reporting "may" be questionable.

On a side-note some Chinese anthropologists question the common human origin "Out of Africa" and instead suggest Chinese or East Asians had their own separate origin. And they seem to be really determined on finding evidence to this end, instead of looking at it from a neutral point of view. This sounds crazy but it's an absolute mainstream idea over there.


While their motives are suspect, just because the current most common theory is that humans originated in Africa doesn't mean that we won't someday learn that this is not correct. Obviously whatever data they find should be treated skeptically, but so should all data. Maybe some day they'll prove their theory or more likely, they won't but a lot of other related data will be discovered and added to the body of human knowledge.


Yep. They need that narrative to push superiority. Genetic be damned I guess.


> some Chinese anthropologists question the common human origin "Out of Africa" and instead suggest Chinese or East Asians had their own separate origin

Where are those claims? Do you have some examples of such claims.


The idea that the modern Chinese are descendanded from Peking man from 770k years feeds the common myth that many people hold that their particular ethnic group is inherently different/superior.

I found this article on the topic very interesting.

https://www.cambridge.org/core/journals/journal-of-asian-stu...


Quite a large number of leading Chinese paleoanthropologists have been in this camp. Take Jia Lanpo or Wu Liu as examples.


> Quite a large number of leading Chinese paleoanthropologists have been in this camp. Take Jia Lanpo or Wu Liu as examples.

Which of Jia Lanpo's work claimed this? I couldn't google one.

Citations to Wu Liu's work would be great as well.


The issue you probably ran into is that Chinese academics don't always publish in English. Often what you get are press statements like [1] espousing a particular position. For Jia Lanpo the situation is a little easier. He was notorious for his position that Chinese humans originated in China. See [2] if you want a direct citation or [3] for context.

For Wu's work, [4]. I doubt it'll be clear to anyone unfamiliar with the literature how this differs from modern models so I'll attempt to explain it:

Way back in the 90s, we didn't have ancient DNA techniques and the idea of AMH-Neanderthal admixture in modern populations was still a bit fringe. The consensus model at the time was that Out-Of-Africa meant population replacement of archaic humans without admixture. A few months before this paper was sent for review, Green et al. [5] published the first Neanderthal draft sequence, which clearly pointed to admixture in Out-Of-Africa model. The consensus model went down in flames and everyone accepted admixture on some level. We're still fully working out the details though.

Liu's paper takes things a step further. Instead of just attacking the now-dead OoA replacement model, they point to Green et al. to say "AMH could have evolved from archaic humans in Asia and we have modern morphology that predates out-of-africa, even with admixture", thus remaining within assimilation theory without really remaining inside it. They also take a neat sideswipe at (modern) consensus with the phrase "imprecise inferences from extant genetic diversity".

[1] https://www.deseret.com/1995/8/15/19187840/chinese-scientist...

[2] Chia, L. P., & Jia, L. (1980). Early man in China. Beijing: Foreign Languages Press.

[3] https://doi.org/10.2307/2659506

[4] https://doi.org/10.1073/pnas.1014386107

[5] https://dx.doi.org/10.1126%2Fscience.1188021


> For now, the paper authors say they do not want to risk destroying the tooth or other bone to get DNA or protein.

Yes it might mean their claims of being a new species could be invalidated, but it would be far more exciting if a Denisovan had been finally found.

Another paper published recently looks at Denisovan DNA in populations of South East Asian Island populations.

http://www.sci-news.com/othersciences/anthropology/southeast...


> Yes it might mean their claims of being a new species could be invalidated

Well, if you think they are bad, why not think them as the worst.

Maybe the whole Dragon Man is a hoax... Right?

Intellectually, I never really understand the mind behind this type of comments... Such minds seem cannot reason long and far enough, but they are very good at distrusting anything...


Well as one gets older you notoce a great amount of nonsense and get cynical. The cynical taking isn’t always correct, and a LOT of people take it too far but mild cynicism is a good bet


Recent and related:

‘Dragon Man’ skull may be new species, shaking up human family tree - https://news.ycombinator.com/item?id=27638218 - June 2021 (118 comments)


For those without access to the full text, here's a related news article on Science with a bit more context: https://www.sciencemag.org/news/2021/06/stunning-dragon-man-...


Humans used to have significantly bigger brains 35,000 years ago. Can you imagine?

https://www.discovermagazine.com/planet-earth/the-human-brai...


Does not necessarily mean more intelligent.


But it could! I’ve always suspected some form of domestication syndrome affecting our species. https://en.m.wikipedia.org/wiki/Domestication_syndrome


I've never understood this brain size correlates with intelligence idea. I keep seeing it and it just makes me think "what? really? still?"

There's dozens of easy non-intelligence hypothesis that can be readily tested: Maybe the skull was larger because it helped balance the weight better for swinging through trees, maybe it was more protective against impact. We can sit around and make up lots of stories to explain this.

Besides, human brains are about the same weight as walruses. If size = intelligence, I'd expect to be chatting with walruses on the phone, working with them at the office... Or what about elephants? Their brains are 4 times bigger!

There's no way it makes sense upon any cursory analysis. It's just a carryover from phrenology.


> If size = intelligence, I'd expect to …

Your understanding of “intelligence” is quite anthropo-centered, of the XXth century-office-work style…

Nothing ever _requires_ that intelligence has to express itself in a consistent/compatible way across species and their own environment.

Perhaps, for instance, some large brain species did not “evolve” as homo sapiens did, because they were more intelligent of their surroundings.


But brain size does correlate with intelligence, 0.3-0.4. It accounts for about 15% of variability.

https://www.scientificamerican.com/article/does-brain-size-m....


This is really sloppy journalism. They see a correlation between longevity, income, career, and cranium size and then say "welp, clearly it's the brain size"

No, clearly it's the money. They go in with phrenology bias and can't really do solid science. They even use IQ numbers which have been shown to correlate with parents income more than almost anything else.

They even mention the career of hedge fund managers, the classic career along with real estate and politics of dullard rich kids.

As the article contributes they then point out everything that I did. I don't know if the editors wanted this style or what.

It opens with paragraphs of clearly specious bullshit then says it's bullshit then has a concluding statement about how it's nonsense.

Second to last paragraph

> So it is not brain size, relative brain size or absolute number of neurons that distinguishes us. Perhaps our wiring has become more streamlined, our metabolism more efficient, our synapses more sophisticated.

Yeah, duh, of course it's more complicated then "durr it's bigger". And of course it's all skewed by the instrument of measure.

It's probably really stupid dumb things like the nuances of human emotions and our success in transmitting them. What sets is apart from other animals likely isn't what 30 year olds can do but what 30 week olds can


Within the same species, that makes sense. Same architecture, more folds, more neurons.


I have wondered if the best explanation for domestication syndrome and neoteny in humans is that our species was bred into existence as pets by another humanoid race.


Doubtful, humans would make terrible pets.


Not quite the same, but all races of humans have had/been slaves at various points in history.

It's not a pleasant subject, but we should not be blind to it, especially when underground and even open air market human trafficking still happens in many places around the world.


There is a difference between a pet and a beast of burden


Great, now I'm going to have that Porno For Pyros song from the 90s stuck in my head all day.


That doesn't suggest a reduction in intelligence .. ?


Yes, but being able to work productively in larger groups often means more for sophisticated tool use than an individual's intelligence.


"Intelligence" is a vague complementary attribute like "attractiveness" and it doesn't seem like you can do anything with the concept except make post-hoc fallacies with it.

Nothing that "lacks intelligence" (a monkey, a person with dementia, a person who reads slowly) behaves all that similarly or is actually lacking the same single thing that causes them to "not be intelligent".


Intelligence of the members is exactly what allows working productively in larger groups. See for instance: dunbar's number and how it was derived


but it could be


Wasn’t that the premise for Idiocracy?


Especially since human intelligence is distributed — it isn't just in the brain but it is distributed across other people and artifacts.

https://en.m.wikipedia.org/wiki/Distributed_cognition


Good point.

It could well be that our brains are more efficient (or more specialised) than earlier human / proto-human brains.

Given the prodigious energy expenditure of the human brain, any gain in efficiency or shedding of unnecessary capabilities could well be a net win.


I have always found this theory questionable because the shrinkage happened somewhat uniformly across disparate human populations. There's no reason that every significant human subpopulation would suddenly evolve more efficient brains at the same time.


There's evolutionary pressure to reduce brain size because big heads make childbirth more injurious/lethal to the mom. I find it quite plausible that it would happen everywhere along a similar timeline.


I see what you’re getting at, but wouldn’t the same pressure to reduce head size also inhibit the heads from getting big in the first place?


The fitness target isn't a stationary one.

Larger heads might have been facilitated by a larger pelvic girdle (this seems to be the case in Neadnderthal skeletons AFAIU), which is an adaptation which would enable large (and possibly inefficient) brains, but at a cost for bipedal mobility, speed, and/or efficiency.

Supposing a later competitor emerged with 1) smaller and 2) more effcicient brains as well as 3) narrower hips, then the previous advantage would become a (comparative) liability.

It's a bit like Clayton Chistensen's Innovator's Dilemma: evolving yourself (or your species) into a corner. Advantageous for a while, but ultimately maladaptive, and hard to back out of.

As with my other comments here, all but entirely conjecture.


Exactly. And clearly there was pressure to downsize heads! But the tradeoff was that we lost brains, and until 40k years ago, that wasn't worth it.

But with the advent of proto-civilization, the calculus changed...


Disclaimers first: I'm not a geneticist or even remotely close.

I'm mostly aware of this dynamic from h. sapies and h. neanderthalensis (or h. sapiens sapiens* and h. sapiens neanderthalensis* comparisons. In a nutshell, Neanderthals were in numerous ways the apparent heavy-duty / high-output model, Sapiens the more efficient / economy model. Neanderthals had larger muscles, shorter limbs (less speed but greater strength, simply on leverage), and larger cranial volumes. All of which would have, everything else being constant, increased overall energy demands.

Mind: this is all my own conjecture, though I wouldn't be surprised to find some literature suggesting similar mechanisms.

Where Neanderthals were competing against other mammalian species and each other, the differentiation was apparently favourable. Possibly also in an ice-age climage.

With Sapiens on the scene ... Neanderthals largely disappeared from the record, though in all likelihood also interbred with Sapiens to some extent. For whatever the reasons, the Neanderthalic adaptations seemed less suitable than the Sapiens ones. The presumption is that this was a fitness selection, though it could well have been other factors (mating preferences, superior numbers for Sapiens, dumb luck and/or chance).

But ... in general, while bigger can seem better and more appealing for various reasons, it often is not, and adaptations which require higher energy or have a higher minimum sustaining requirement ... could well prove to be less suitable especially where the environment itself is in transition, or where resources are highly marginal.

There is a fair bit of research into the loss of vestigal function, particularly among sequestered cave populations such as blind fish and invertebrates. It turns out that visual processing has high energy demands, and in an environment in which sight conveys no advantage, lack of sight is actually advantageous, as it reduces neurlogical metabolic load (by as much as 1/5 to 1/4 if I'm recalling my sources correctly).

In the case of "Dragon Man", we're looking at a new instance and have little data to go on. But other homo variants and general evolutionary trends suggest at the very least possible directions.


Newborn humans have more neurons than adults do, to this day.


If I had access to a genetically identical infant, before its aware mind had formed, and I transplanted its brain into my own (suitably expanded) skull, could I grow a larger, coherent, brain? Would the younger neurons give me neuroplasticity? Would this increase my ability to learn? Would people who had undergone this procedure be more prone to schizophrenia -- which I think of as multiple minds trapped together in one brain and body?

If cities are more economically productive than separate villages, because they increase communication among people... well, how much higher-capacity a communication channel than brains literally wired together? You can do better than bike lanes, people.


Newborn humans are more intelligent than adults.

(If we use the conventional definition of "intelligence" as "capability to learn and acquire new skills".)


Is that the conventional definition? People here seem to be using it as some combination of "sentient" "creative" and "can do math problems in their heads". There's a lot of confusion between future and present capability in its usage.


it could mean more potential for intelligence


Among modern humans, brain size is correlated to body size, meaning that, on average, a taller being has a bigger brain, and vice versa.

Assuming that brain size is correlated to intelligence implies that, on average, taller people are more intelligent!


One bit of confusion for me was the dragon part of the name.

Peking man was discovered near 'dragon bone hill' (Longgushan) back in 1921 in Zhoukoudian, but this Dragon man was discovered in 1933 in Heilongjiang, and hence the name "Dragon man" (the 'long' (龍) part of the place name meaning dragon). Lots of place names contain dragon this or that in China. These two specimens are not contemporary but separated by at least a 100 thousand years.


I was originally thinking that a Sapiens/Denisovan hybrid of the sort we've seen elsewhere might be a possibility too but the skull is too old for that to make sense. I almost said "human/Denisovan hybrid" but really Denisovans are a sort of human too.




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