Just a week after scientists reported evidence that our species left Africa earlier than we thought, another discovery is suggesting the date might be pushed back further.
Homo sapiens arose in Africa at least 300,000 years ago and left to colonize the globe. Scientists think there were several dispersals from Africa, not all equally successful. Last week's report of a human jaw showed some members of our species had reached Israel by 177,000 to 194,000 years ago.
Now comes a discovery in India of stone tools, showing a style that has been associated elsewhere with our species. They were fashioned from 385,000 years ago to 172,000 years ago, showing evidence of continuity and development over that time. That starting point is a lot earlier than scientists generally think Homo sapiens left Africa.
This tool style has also been attributed to Neanderthals and possibly other species. So it's impossible to say whether the tools were made by Homo sapiens or some evolutionary cousin, say researchers who reported the finding Wednesday in the journal Nature .
"We are very cautious on this point" because no human fossils were found with the tools, several authors added in a statement.
It's not clear how much the tool development reflects arrival of populations or ideas from outside India, versus being more of a local development, said one author, Shanti Pappu of the Sharma Centre for Heritage Education in Chennai, India.
The tool-making style was a change from older stone tools found at the site, featuring a shift to smaller flakes, for example.
Michael Petraglia, an archaeologist who specializes in human evolution in Asia but didn't participate in the work, said he did not think the tools show that our species had left Africa so long ago.
"I simply don't buy it," said Petraglia of the Max Planck Institute for the Science of Human History in Jena, Germany.
Instead, he said, he believes one of our evolutionary cousins in India developed the tool style independently of outside influence. The tools at the site northwest of Chennai in southeastern India are closely related to the older tool-making style there and seem to represent a transition, he said.
The idea that they reflect knowledge brought in from elsewhere would be tough to prove in India, he said. The country has few well-studied archaeological sites and only one fossil find from this period, from a forerunner of Homo sapiens that was associated with the earlier style of tool-making, Petraglia said.
Explore further:
Moroccan fossil find rearranges Homo sapiens family tree
More information:
Kumar Akhilesh et al. Early Middle Palaeolithic culture in India around 385–172 ka reframes Out of Africa models, Nature (2018). DOI: 10.1038/nature25444
rrwillsj
Some researchers claim that the Toba event drastically reduced the hominid population to just a few thousand of our Homo Anthropophagus ancestors.
However, other researchers are claiming not to find a widespread extinction event among other animals or plantlife.
It has been my (unverifiable) opinion that there was a lot more migration via rivers and along coastlines with dugouts or rafts. And that was what made them vulnerable to a major volcano blowing off with concurrent tsunamis.
wailuku1943
As the article states, the Indian subcontinent is very poorly-known archaeologically. That's a great pity, because good look at the map shows that it's an excellent candidate for an eastward migration route.
As is so often the case, the operant phrase is "stay tuned."
Nik_2213
Also see... https://en.wikipe...rvolcano
Osiris1
Osiris1
Stevepidge
Ojorf
Yes, genetic analysis is sooo political.
Get real.
Stevepidge
You mean the same genetic analysis that Jews claim make them a "people".
Thorium Boy
Ojorf
Get real.
wailuku1943
rrwillsj
Stevepidge
Oh really? I thought it was a religion... Oh they are a people when convenient and a religion when not?
I guess this geneticist is a fraud huh?
https://forward.c...ce-atta/
Stevepidge
Define failure? Failure of what? What does bigotry have to do with failure? Are lions bigots for viciously favoring their own feline genetics? Are they failures? Are Slave making ants failures for being bigoted towards their own species and enslaving their own "kind"? You ACTUALLY believe that intelligence was achieved by solely being a goody two shoes? You really are naive. You are just weaponizing words for political points, too bad you wield a limp noodle.
Ojorf
Stevepidge
species is merely word and ill defined method of categorizing life.
Ojorf
What are you getting at?
What are you trying to justify.
You seem to want to split up humans into different species, why?
Stevepidge
Stevepidge
Ojorf
Speciation happens gradually, of course there is no set in stone line, so what?
Different species, different life forms, call them what you want, they still exist.
You sure could try to argue that bees are actually an expression of plants, but you would fail.
Stevepidge
You still have not addressed the reasoning behind the classification of wolves and even dogs as separate species. Yet humans are somehow immune to speciation despite being genetically more "diverse".
Ojorf
Because it is not true, science proves it. Why would I not oppose a false concept?
Ojorf
OK, I see your mistake.
Human genetic diversity is substantially lower than that of many other species and the out of Africa theory has been proven correct by genetics.
Stevepidge
You said "Just because there is not some clear line that can be drawn between some species does not mean that a species does not exist"
This tells me and any real intelligent person that you are drawing the lines of species arbitrarily. Let me give you an example. Take the sun for instance. How do we define the sun? Do we define the sun by the extents of it's light? Or the extents of it's heat? No, we arbitrarily define the physical sun by the extents of it's plasma. You are in essence arguing where the fist begins and the hand ends. By the way "science" is never settled nor does it supply "truth", it only reinforces preconceived narratives in an attempt to furtively influence the conscious direction of perception.
Stevepidge
More genes does not equate to "greater diversity". It is the QUALITY of the genes not the number that counts. 25,000 vs 500,000. Wheat has 500k but for all it's "diversity" it sure doesn't stop the combine ( developed by the less diverse 25k humans) from harvesting their brethren lol.
Stevepidge
Ojorf
No, I'm talking about genetic diversity within a species.
Ojorf
You should question your sanity, there is indisputably more genetic diversity in chimps than humans.
Maybe you are confused with phenotypic diversity.
Stevepidge
And? Is phenotype not a function of genetics? What exactly is your point? You are ascribing importance in an arbitrary manner, or worse yet , you are interpreting data to support a political or social narrative.
jonesdave
No, I just think he is terminally confused, full stop. There is also more genetic diversity within Africa than outside of it, which also points to an 'Out of Africa' scenario.
Stevepidge
Everyone is terminal. At least I'm not deluded.
jonesdave
I disagree. As does the science.
Stevepidge
Who is this science? Where can i meet him?
jonesdave
Point made, methinks.
monstercolorfun
This conversation seems to have become deluded with a UFO abductee called StevePidge from Alabama claiming that the low genetic diversity of humans away from africa is not the same as when he takes an african plant home from the garden center and claims that he is supplying the garden center with the african plants, even though they have 500 different colors of them and he only has a pot with a garden center label in it.
No one is charmed in your delusion StevePidge, it's like when mr nobody was taking my stuff in school. Steve still exists in mr nobody world... and he will take us all on if we say that mr nobody doesnt exist. END OF STORY. BYE STEVEPIDGE.
rrwillsj
Otherwise all the whiny bigots wouldn't be raping every unprotected female they can catch. Otherwise it's bestiality. The very definition of bigot as a subhuman subspecies.
As the recent article on zebras pointed out. It was overly enthusiastic nineteenth century explorers and naturalist that insisted there were six separate species of zebra based entirely upon external features. And they were wrong.
It does not matter how many books or articles they published on the subject. Nor on how many professional awards and degrees were bestowed. Or how many public and academic lectures they gave extolling their conclusive findings.
They are now proven wrong through new technology and evolving procedures.
We should all consider this embarrassment before we claim we alone have the FINAL TRUTH!
Ojorf
You have it backwards again.
You can have very low genetic diveristy with high phenotypic variability, think domestication.
This happens due to pleiotropy.
Google "peliotropy" in relation to domestication, if you dare.
jonesdave
No, I think you have misunderstood. By the time they got to the Americas they may have been pale skinned. Not surprising given that they came over from Siberia. Europeans are light skinned, for the most part. However, the ancestors of the native Americans left Africa ~ 50 000 years before they got to America. And at that stage they would have been dark skinned.
Stevepidge
And? What of it? Phenotypic variability is still just a physical observation of genetic change. What is your point? You keep making arbitrary distinctions. How are phenotype changes recorded? In the Genome. It's all genetic. you are like a barber who claims to be a "spit end" specialist that does not work on hair.
Stevepidge
Key words here. MAY. 50,000 years lol. Even your dating systems are not capable of accurately determining age that long ago. 50,000 years ago is so long ago that it is impossible to know what happened or what takes place over such long periods. Yet we have all these "intellectuals" claiming to know and possess truth through their "scientific" study. Get real. Better yet, get a real job.
Stevepidge
This is not even intelligible banter. You are quite strange.
jonesdave
Wrong. We can date rocks going back 4.6Ga. 50 000 yrs is a breeze.
Wrong. Multiple lines of evidence tell us when the most recent common ancestor left Africa.
How about getting an education? You obviously know nothing about the subject. Just another Dunning-Kruger blowhard.
Stevepidge
Ojorf
See, you don't even get my point, you keep getting it wrong. Let me try again.
Phenotypic variability in a species has little to nothing to do with genetic diversity.
You cannot tell anything about genetic diversity in a species by looking at it, get it!
The only way is to look at the genetics, duh.
Ojorf
You are correct, this is beyond STUPID.
How can you have intelligent banter with someone who asks ridiculous questions like that?
You are obviously in denial and feeling insecure.
It is an impossible and thankless task trying to defend a position that had its foundations ripped from under it with the introduction of genetic sequencing.
Unfortunately for you the genome of a species is clear map of genetic changes through time and even if it cannot be precisely dated the basic cladistics are clear as a bell.
jonesdave
Wrong. Again. You are obviously not very well educated, so I won't go into huge detail, but one can, for instance, for relatively recent times, date a volcanic eruption. You can then have a look in the ice core data to check that date. You can also use different types of dating; say K/Ar, ESR, etc. However, like I say, this all seems to be beyond your pay grade, so you carry on believing whatever helps you sleep at night. Just don't forget, before you nod off, to say a little thank you to your (black) forefathers.
Stevepidge
Once again you completely ignore your built in assumptions on steady decay rates and the original composition of the sample. Figures you would just ignore such a simple logical problem with radiological dating of all types. With argon especially it seems to me to be a certainty that water and gas will enter rocks through tiny cracks and invalidate almost all radiometric ages. I suspect your (black) forefathers did not bequeath you enough erudition.
jonesdave
It seems to you? Lol. I couldn't give a tupenny cuss what you think, you are an irrelevance. Link me to the science behind your baseless assertions. You're opinion is of no value.
Stevepidge
"Experience has shown, and a true philosophy will always show, that a vast, perhaps the larger, portion of truth arises from the seemingly irrelevant."
― Edgar Allan Poe, The Mystery of Marie Rogêt
Your self inflation means nothing to me, your spells are powerless in the face of truth. Ignorance is your commodity for you are poor of mind and wisdom.
Ojorf
rhugh1066
jonesdave
Yep, definitely dealing with a crank here. All word salad, no science. You're not Thornhill, by any chance?