Neanderthals survived on a knife's edge for 350k years (science.org)

by Hooke 204 comments 238 points
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204 comments

[−] netcan 45d ago

>somehow Neanderthals managed to survive across most of Eurasia for nearly 400,000 years, longer than modern humans have been on Earth.

These narrative simplifications end up just being confusing.

Neanderthals from 400kya are often classed as Heidelbergensis. These guys were less Neanderthal-ish and more similar to us... being closer to and less divergent from the sapiens-neanderthal LCA. Neanderthal-Denisovan divergence occurs at this time.. so calling them Neanderthals rather than Neanderthal ancestors is kind of messy.

There is a shortage of fossil evidence from this and earlier periods... It's called the "muddle in the middle."

In any case.... Sapiens also had ancestors at this time. We don't have fossils, but something has to be our ancestors. So if we are calling Neanderthal ancestors from this period Neanderthals... it would be more consistent to call sapien ancestors sapiens.

Individual populations may have been insular, small and most died out. But... there were people everywhere.

Humans existed over a vast range. From south Africa to Northern Eurasia. East to west. At this point in time... I think it's confusing to think of neanderthal/denisovan/sapiens as different species.

Individuals may have been inbred... but the overall genetic diversity across the whole range was greater than the genetic diversity we have today. In some sense, we are the inbred ones.

Also... population estimates are pretty dicey. We don't really know. Could have been booms and busts. Could have been ideal habitats with higher populations.

We still have a fairly poor grasp of human "natural history"

[−] jarjoura 45d ago

> Neanderthals from 400kya are often classed as Heidelbergensis.

Heidelbergensis is the last common anscestor of Neanderthals, Denisovans and us.

We were all around for just as long, 400kya+, and before that, it was Homo Erectus.

All of them, Erectus, Heidelbergensis, Neanderthals, Denisovans and Sapiens were walking around at the same time. There's plenty of fossil records we've uncovered that show that to be true.

It was only in the last 100k years or so that we remained and the other variants "died out".

[−] netcan 44d ago
Heidlebergensis is no longer thought to be on the sapiens lineage. It's probably the ancestor of neanderthals and denisovans. 400kya is around the time of this divergence, based on recent genomics. They were the same species at this time.

The Sapiens lineage is now thought to have diverged significantly earlier.

Erectus existed, but in pockets.

Other lineages existed also. At the very least, Homo naledi. Probably other dwarf lineages, an African "ghost lineage" and probably others.

Neanderthals and denisovans are structured... With subspecies, hybrid zones and whatnot.

There are also many sapiens lineages with no descendants. Most of them.

[−] AlotOfReading 44d ago
We shouldn't use the word "species" lightly with hominins. There's no accepted way to properly classify archaic humans.

For example, some paleoanthropologists classify most archaic humans as h. sapiens. Anatomically modern humans become h. s. sapiens, neanderthal become h. s. neanderthalensis. This incorporates the middle pleistocene hominins from mainland Asia pretty well to boot. Many of those same people also use the "conventional" binomial terminology when they're not making a very specific point, so you can't just look at usages to understand where they're coming from.

There's also a hundred other classifications, some giving neanderthals their own species, others including it with heidelbergensis, and so on. None of them has clearly "won" and probably won't while we keep publishing "new" transitional forms every couple of years.

[−] netcan 44d ago
Sure... and it would help if there was more consistency in general.

But given that there isn't, we should at least maintain internal consistency. That's what I was commenting on above. You can't use one conceptual framework for Neanderthals/Eurasia and another for Sapiens/Africa. It's confusing... and you end up with statements that are essentially false.

Neanderthal and Sapiens exist approximately concurrently. The "classic neanderthal" form doesn't predate sapiens. It only predates Sapiens if we define "Neanderthal" from the point of divergence. If we do that, we need to define Sapiens the same way. It can't be the establishment of a founder population for one and the emergence of a distinct form for the other.

I'm not advocating for one system or another... or even for the establishment of one consistent system necessarily.

[−] MadDemon 45d ago
Did they really die out, or did the population just merge with modern humans? Most people on the planet have some Neanderthal DNA, so clearly there was some intermixing. If modern humans were a much larger population, it makes sense that the Neanderthals only contributed a small amount of DNA to the gene pool. I could imagine that they were just slowly absorbed into the much larger Sapiens population.
[−] hoppp 44d ago
In Africa most people don't have Neanderthal DNA however in Europe probably everyone has. (I have no idea about Asia, maybe somebody can chip in)

I think they probably mixed in and we just became one, sort of

[−] snovymgodym 44d ago
Virtually every population outside of Sub-Saharan Africa has Neanderthal and Denisovan DNA between 1-4%. This includes all of Eurasia, all pre-Columbian American populations, Aboriginal Australians, Papuans, etc.
[−] ralferoo 44d ago
Is there any research about why Sub-Saharan Africa doesn't have Neanderthal DNA?

Is the argument that the tribe of humans from Africa was good at repelling outside invaders, but themselves expanded outwards and assimilated (and then outnumbered) the other populations, or something else?

It just seems a bit bizarre given that all humans elsewhere have relatively similar amounts (but quite a low amount) of Neanderthal DNA, which seems to suggest a reasonable amount of migration, interaction and interbreeding between populations everywhere except Africa.

[−] AndrewKemendo 44d ago
Yes tons of research

There were multiple waves out of Africa but Most early anatomical human groups never left Africa as a result, there’s more DNA diversity within the continent than outside Africa

Its confusing because the non-african group grew exponentially while the intra-African continent continued to mature

The anatomically modern humans that left Africa spread rapidly and aggressively across the world basically absorbing and destroying every proto-human group and ecological niche and

now the world is ruled by the aggressive narcissistic chimeral hybrid of human (African) Neanderthal (European proto human) and denisovian (Peking man) that survived the exit snd expansion

https://pmc.ncbi.nlm.nih.gov/articles/PMC4067985/

[−] IAmBroom 44d ago
Wow, so many judgments and racist descriptions in one paragraph attempting to describe scientific knowledge.
[−] AndrewKemendo 44d ago
Everything typed above has empirical basis

Feel free to investigate each claim independently and come to your own conclusions

[−] octopoc 43d ago
It sounds like gp is saying non Africans are more narcissistic than Africans. So yeah that needs a citation (or clarification)
[−] selimthegrim 44d ago
You might want to read about the Chadian introgression for the exception.
[−] kabaka 44d ago
Why was this downvoted?
[−] underlipton 44d ago
That's a common misconception that turned out to not be true.

https://www.science.org/content/article/africans-carry-surpr...

It also doesn't hold for the African Diaspora, especially in the Americas (and probably flowing back into Africa as we speak). It's also worth considering that many of the actual traits that Neanderthal-associated genes codes for probably have analogues in the much-wider African genome.

[−] allemagne 42d ago
The version of the claim I believed is that Sub-Saharan Africans (especially as of ~2000 years ago) basically don't have any Neanderthal DNA.

Your follow-up doesn't appear to contradict that (of course this wouldn't hold when populations start mixing in modern times and wouldn't have ever held 100%) so I was confused.

However the article does in fact dispute my previous belief:

>The researchers found that African individuals on average had significantly more Neanderthal DNA than previously thought—about 17 megabases (Mb) worth, or 0.3% of their genome.

This is as opposed to 1-4% of genomes for populations outside of Sub-Saharan Africa.

>They also found signs that a handful of Neanderthal genes may have been selected for after they entered Africans' genomes, including genes that boost immune function and protect against ultraviolet radiation.

>The best fit model for where Africans got all this Neanderthal DNA suggests about half of it came when Europeans—who had Neanderthal DNA from previous matings—migrated back to Africa in the past 20,000 years.

"The past 20,000 years" is pretty broad and seemingly includes modern era exchanges, but AFAIK that can't account for selecting Neanderthal genes or for how widespread Neanderthal DNA already is.

[−] netcan 44d ago

>Did they really die out, or did the population just merge with modern humans.

Most populations die out. Most sapiens. Most neanderthals. Most everything. The chance of becoming an ancestor is very, very low.

Neanderthals were not slowly observed. Most of our neanderthal DNA comes from a single mixing event/period.

Evolutionary history is a history of bottlenecks. Small populations that survive and become large populations. The rest don't make it.

[−] Betelbuddy 44d ago

>> Did they really die out

There are a few still. One made it to President of the USA.

[−] bit-anarchist 44d ago
Do not speak ill of the Neanderthals.
[−] stvltvs 44d ago
True, but I'm guessing they're referring to anatomically modern humans which have only been here for a couple hundred thousand years. Not sure that's a meaningful way to look at it since I'm assume Neanderthals also evolved somewhat during that time.
[−] astrobe_ 44d ago
One thing that confused me in TFA is that it says that "[neanderthals were] maybe a couple of thousand breeding individuals", yet they were enough to inter-breed with sapiens at some point(s) [1]. In my mind, tribes of "far-flung populations of just a few dozen individuals" would be shy and difficult to find.

[1] https://en.wikipedia.org/wiki/Neanderthal_genetics

[−] imadierich 45d ago
[dead]
[−] hax0ron3 45d ago
It's wild to think how long very human-like beings and modern humans existed before the technological revolution really took off. Hundreds of thousands of years of existing on the technological level of stone tools, spears, cloth made out of hides, and fire. Then at some unknown point probably in the last 100,000 years, the bow and arrow. Then about 12,000 years ago, the agricultural revolution, which probably unlocked much of the subsequent technological progress by enabling more food security and larger populations.
[−] dainank 45d ago
I think it is also interesting to realize that we have had a huge population boom since the last 50 years or so, thus currently, the entire world population alive makes up roughly 8% of the entire population of the world since the existence of Homo Sapiens. In summary, if you were to be randomly born as a human, you would most likely be born in the latter centuries, rather than the early ones, since the sheer amount being born recently than many years ago is so much more.

https://www.sifrun.com/how-many-people-have-ever-lived-on-ea...

[−] roncesvalles 45d ago

>the technological level of stone tools, spears, cloth made out of hides, and fire.

Don't forget, there are pockets of our species living at this level to this very day (uncontacted tribes)!

[−] jarjoura 45d ago
Can't imagine having to live with anxiety of just staying alive. Constant diseases, infestations, starvation, animal attacks.

You would never feel like you have time to just, be. Instead you're focused on getting your next meal, and finding a place to sleep.

It only took a few ice-ages to force us to get smart about how we organize and then here we are.

[−] detourdog 44d ago
I think rope, twine, and weaving needs to be recognized as significant technical development. That has little record but would have been combined with wood for simple machines.
[−] IAmBroom 44d ago

> Then at some unknown point probably in the last 100,000 years, the bow and arrow.

The atlatl was undoubtedly earlier, and a bigger advance. It essentially doubled a hunter's arm length, and thus impelled speed - with force proportional to the square of speed. An atlatl can put a dart straight through an enemy's gut, or easily pierce a deer's hide.

[−] tim333 44d ago
There seems a bit of an acceleration ~ 50-100k years from evolving brains similar to modern ones to agriculture, ~8k year from there to writing, ~4k to the printing press, ~400 till computers, ~40 till the web and so on. Each of those has kind of speeded intellectual progress and AI will probably be another speeding up.
[−] jstanley 45d ago
[−] Fricken 45d ago
Also nukes. We've got the whole place rigged to blow in case a few of us just doesn't feel like it anymore.
[−] tyre 45d ago

> Then about 12,000 years ago, the agricultural revolution, which probably unlocked much of the subsequent technological progress by enabling more food security and larger populations.

It definitely did. Also note that agriculture was invented in multiple places over time. Unfortunately, the Native Americans did not invent it quickly enough, so they had far less time for technological development before Europeans arrived. At which point, it was too late.

[−] Nevermark 45d ago

> Harmful mutations can accumulate through inbreeding. Yet somehow Neanderthals managed to survive across most of Eurasia for nearly 400,000 years

It is also true that inbreeding for extended periods weeds out both dominant and recessive bad genes very effectively. As long as at least one good or not-so bad alternative is maintained.

So not as surprising that small groups can last a long time, once they reach a threshold, as implied by the article.

It’s a brutal way to improve the stock, as lots of individuals suffer until (and in service of) a debilitating gene going “extinct”. And every new maladaptive mutation restarts the process, but it works.

On the upside, any adaptive mutation can just as quickly become pervasive.

The biggest downside in the long term is a lack of genetic diversity as a shield against new diseases.

[−] atleastoptimal 45d ago
350,000 years of just chilling, picking berries, you die in identical technological and cultural environment as when you were born. Now we got to be around when God is made in a data center
[−] lobf 45d ago
I spent a year of high school in the Basque Country, and it always stuck out to me that a common feature of the Basques, especially the beefy ones, was incredibly caveman-like.

I know this is not unique to this population, but I also always wondered if it correlated to the fact that it is one of the historic Neanderthal populations. I have a photo of a dude I used to play soccer with that looks like I put a Neanderthal model from the natural history museum in a jersey, and I have met very few people like that in the states. The Basque Country is a very small population.

[−] Glyptodon 45d ago
I know even with humans pre-modern populations were drastically smaller, but it's still just astounding to me how small of a population size it seems like Neanderthals had.
[−] Fokamul 45d ago
Seventy years ago, a scientist published a book about Neanderthals. According to his scientific opinion, they didn’t speak; they communicated only through hand gestures and had to go to sleep early because they couldn’t see those gestures at night, lol.

In my country, there is an area with archaeological sites of Neanderthal villages and their mammoth hunting grounds. In one area, there are thousands of mammoth bones. Imagine having only wooden spears and ordinary stones at your disposal. Maybe flint spears, maybe not. In this area, flint is too rare and is mainly used for cutting, because the nearest flint deposit is 400 km away.

[−] zkmon 45d ago
The phrase "survived on a knife edge" or the dramatization is a product of awareness of modern living. For them at those times, neither "survival" nor "struggle" has any meaning. There was likely no consciousness of such concepts. They just continued via instincts and evolutionary goals such as reproduction, food gathering, hunting etc, which were just the same activities their ancestors did, with no changes. Lack of change should actually mean pretty normal life, instead of rapid change-related struggle that we go through now.
[−] ghtbircshotbe 44d ago
I liked the recent Nova episode on neanderthals. They talked about how awful the last ice age was for the neanderthals despite being adapted to cold climates, and how modern humans survived it by staying away until it got warmer.
[−] tsoukase 44d ago
As is usual for such a distant past, we can't answer basic questions: how many persons and where they were distributed, how their evolution and life was and mostly why intermediate species between modern human and the rest of primates don't survive today.
[−] shevy-java 44d ago
What is more interesting is how they went extinct.

I would assume there were local populations that lived for a long time. But then they were gone too.

Some DNA is in modern humans, so there must have been some inter-breeding, but that in itself alone can not explain why the Neanderthals went extinct.

[−] prplxd_nihilist 44d ago
The females in this article look exactly like modern age humans, the males have these long beard but apart from that there is no visible change in the looks. Far different from what we used to see depicting neanderthals. Is that AI generated?
[−] razorbeamz 45d ago
Perhaps some cultures' stories about "wild men" are about Neanderthals.

Maybe Enkidu from the Epic of Gilgamesh was one.

[−] brador 45d ago
Food, water, then the RNG is solved by large N.

Was it a knifes edge at times? Sure. Was it abundant at times? Also true.

[−] SarahC_ 45d ago
Shouldn't have bothered....
[−] mproud 45d ago
How ironic that the science.org website wants to verify I am a human!