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Can someone link to a kind of summary of the current best understanding of human evolution and dispersal? It's really fascinating to me.
Until recently, I had naively understood "Out of Africa" to mean that homo sapiens evolved in Africa from some sort of ape like thing and then went out and conquered the world. But the idea that homo sapiens is just one of many kinds of human species, and that other ones like Neanderthals and Denosivans left Africa earlier (or evolved from homo erectus who left earlier still...?) is really mind blowing. It's weird to me to think of multiple human species living at the same time.
The general consensus up until now is, roughly:
Homo Erectus: 1 million B.C. to about 500,000 B.C.
Homo Neanderthalensis and Homo Sapiens split off from common ancestor: 500,000 B.C.
Homo Sapiens dominate Africa until about 70,000 B.C. when they spread into Europe, Middle East, and Asia.
Neanderthals dominate Europe, Middle East, and Asia, until 70,000 B.C. when Homo Sapiens return out of Africa.
There are a few other variations of humans in the 300KYA to 70KYA period, including: Denisovans (found in Siberia and other places), the "hobbits" found in Indonesia.
It's possible and likely that around 100KYA, there were several species of humans cohabiting the earth, including modern humans (H. sapiens), Neanderthals, Denisovans, a few remaining H. Erectus, the hobbits, and some mixtures of the above.
Each discovery sheds new light and sometimes, as with this possible modern human skull, shatters old theories about the timeline.
It's fascinating to think that at one time in the not-too-distant past, there were multiple species of humans in existence, of which only one survived, though most non-African humans today carry 2-4% Neanderthal genes, so in a sense, some traits of the Neanderthals survived. We are the Neanderthals.
It's time we stopped using the term "Neanderthal" as an insult. They were possibly as smart as modern humans, had larger brains, had tools, ritual burial, weapons technologies, and art work. Their anatomical structure indicates that likely they had language. It's possible that they were gentler than H. Sapiens which would explain how they got gobbled up and made extinct, despite their vast strength (Neanderthals bone structure and muscle attachments indicate that they were many times stronger than modern humans.)
Sort of a tangent, but I've wondered before if the "Nephilim" mentioned in Genesis could have been some distant memory of when Humans coexisted with Neanderthals.
From Wikipedia:
When people began to multiply on the face of the ground, and daughters were born to them, the sons of God saw that they were fair; and they took wives for themselves of all that they chose. Then the Lord said, "My spirit shall not abide in mortals forever, for they are flesh; their days shall be one hundred twenty years." The Nephilim were on the earth in those days—and also afterward—when the sons of God went in to the daughters of humans, who bore children to them. These were the heroes that were of old, warriors of renown.
— Genesis 6:1–4, New Revised Standard Version
Sounds a lot like what we know about Neanderthals.
Also Genesis is sort of the "deep memory" of humanity. Especially the first few chapters.
> They were possibly as smart as modern humans, had larger brains, had tools, ritual burial, weapons technologies, and art work.
But the new discovery discussed in the article throws that into question. As the Atlantic writes:
https://www.theatlantic.com/science/archive/2019/07/apidima-...
> The identity of Apidima 1 could also cast doubt on other archaeological finds from Europe, such as stone tools with no accompanying fossils. Researchers had long assumed that within a certain time window, “any archaeology was all the work of Neanderthals,” says Wragg Sykes. But if modern humans also occupied this “safe range,” which species actually created those artifacts?
> Homo Erectus: 1 million B.C. to about 500,000 B.C.
Can you imagine the period of sheer..uneventfulness?
It's an indescribable unease for me, imagining a planet where nothing really happens, just animals doing their thing... Even worse if you're a semi-sapient species, with just enough awareness to know that things could be better, but not seeing any improvement in your entire life..
I mean, imagine us staying basically the same for the next 50 years, with nothing really changing in human society, let alone a 100 years, let alone a 1000...
> there were multiple species of humans in existence, of which only one survived
If there were other sentient species on this planet co-existing with us, we probably killed them all.
You might enjoy Yuval Noah Harari's book Sapiens. It's written for a general audience and I got a lot out of it.
However Sapiens is not about pre-history. It's about history and written by a historian.
Homo ergaster had its own "Out of Africa" moment several hundred thousand years earlier, and branched into several subspecies like homo erectus; up to a million years before, there was even other homo species (maybe homo habilis?) that left Africa to become for instance homo georgicus.
This is a good site - https://courses.lumenlearning.com/suny-history-of-our-tribe/
https://www.stuffyoushouldknow.com/podcasts/what-happened-to...
Doesn't exactly hit your question but gives a good overview.
On a darker note, one could almost see it as a form of mercy that none of the other species survived into the era of civilizations. Given our willingness to enslave other humans, I can only imagine what would have been done with "lesser" humans.
well they sort of did - modern Europeans are now acknowledged to carry some Neanderthal DNA (estimates go somewhere between 1.5-20% depending on how you count)
People who think that Neanderthals/etc were "lesser" humans (for whatever bogus reasons) probably also need to conclude (for the same reasons) that Europeans are also lesser humans
Given our propensity for war and genocide, I wonder if humans just killed off all the other near species?
In the beginning of Yuval Noah Harari's book Sapiens, he discusses the history of Homo neanderthalensis (Neanderthals), Homo erectus, and Homo sapiens. He discusses their history amongst eachother and why/how Homo sapiens succeeded. It then goes onto explain why Homo sapiens succeeded and grew into what humans are today (animal husbandry, agriculture, culture, industry, technology, information, etc).
You would probably want to read "The Journey of Man" by Spencer Wells, great book on this topic.
There is also a good PBS miniseries of his work using the same title. One benefit is seeing his interactions with different aboriginal societies and how respectfully he treats their origin stories.
To have a feel of long period of time, I always use one metric: my grand father. He's lived 93 years, so almost 100. 2000 years ago was then 20 grandad away. Not so long ago after all. 200K ago is 2000 grandad away. Quite some time but nothing astronomical yet.
You can also think in terms of generations. If everyone has a kid at 20 then you can draw 100 stick figures in a line to go 2000 years back. Not so long when you look at it.
So this person 200k years ago was roughly 10000 generations ago. That's long in human terms and very short in the history of the earth.
If I recall correctly this is one measure used in one of "the science of discworld" books.
...except that a "grandfather" was taken to be 50 years, since what matters is not the length of an individual life, but the time between generations (and the transmission of extelligence). James Burke used it as well in his Connections 2, noting that when his grandfather would tell him about his grandfather telling him about how things were when he was a lad, we were already back to the heart of the industrial revolution.
Life expectancy grew in time, and also the age when having kids. The grandfather from 2000 years ago probably had kids around 20 and lived to 60.
Does it strike anyone else as odd that the two skulls found practically "nose-to-nose" are 40,000 years apart in age? How do two humanoid skulls coincidentally end up right next to each other with 40,000 years gap between them?
Sea mines placed miles apart during the second world war sometimes end up settling right next to each other, several miles away. Sometimes tens of miles away. Sometimes next to a leftover mine from the first world war that arrived the same way.
The environment in which they exist subjects them to varying pressures and forces, making them move. When do they stop moving? When they reach a point at which those pressures and forces cease. That point is the same for all items that get swept there. Wait long enough, and if another one is part of the same system of forces that directs towards the same null point, it'll turn up. Happens with sea mines over the course of a few decades. Could it happen with skulls over tens of thousands of years? Sure could. Happens with lots of objects.
One of the articles I read stated they suspected the skulls were originally in different caves but had been caught in a flood that washed them into a common area.
It was an ancient museum.
Neanderthal had rituals of some kind, maybe they just buried one of theirs with a skull s/he had found laying around?
Although I imagine the likely explanation is just that sometimes things fall next to each other.
What’s the margin of error on these dating methods? Seems like a simpler explanation is that one of the dates is wrong.
It's a good burial place and/or a good place to preserve bones.
> When it comes to figuring out how old something is, archaeologists are interested in one element in particular: uranium.
I though fossils were dated with Carbon-14. Did that change?
C14 dating loses precision dramatically past a certain age (~50k years, IIRC), because of the nature of half-lives. Since this is in the 200k range, C14 wouldn't be the go-to.
Carbon dating is merely one technique in the field of radioisotope dating.
It's scary what humankind set to achieve in next 210k.
Extinction?
> When bone is buried in the ground, it can absorb U-238 from the environment.
How? Is there traceable amount of Uranium-238 in every handful of dirt around the world?
I don't remember specifics from college, but yes, I think there is uranium pretty much everywhere. Oceans, rocks, dirt, maybe not airborne, but everywhere else.
It seems like it should be the opposite right? There is no uranium being exchanged with the environment after burial, so you can determine the age by how much has decayed.
...if the DNA testing proves out. Which hasn't been done yet?
Also discussed here: https://news.ycombinator.com/item?id=20410982
Thanks. We'll merge that thread into this one.
Take the dates with a grain of salt.
Nobody ever got a grant or a paper published for revising towards a younger date. No discovery in that.
> Nobody ever got a grant or a paper published for revising towards a younger date.
Really? Is there a published paper with evidence supporting this claim?
I was wondering if there are any problems with uranium dating
Nice try, Satan. First dinosaur bones are planted to trick us, and now this?!
Please don't do this here.