Near extinction of humans some 70,000 years ago

It seems the human race was down to around 2,000 individuals about 70,000 years ago.

Interestingly enough, homo sapiens began to exhibit behavior characteristic of modern humans about that time.

Technology took a huge leap forward:

All of which has led anthropologists to speculate that difficult times experienced by the remnants of the human population spurred them to greater achievement, and that perhaps the less adaptable among them perished, leaving those 2,000 (or so) survivors to give birth to the human race.

 

I've always been fascinated by this. I've actually heard the number put as low as 500 hundred mating pairs, which is pretty scary. But it does explain our lack of genetic diversity compared to most other species.

 

Well good there are billions of humans now so our odds of survival as a species in the face of climate change is even better.

 

If you are anywhere near San Francisco, the Academy of Science has a small but very good exhibit on human evolution, which discusses this issue some.

 

Great flood duh... and it was less people... and like 8000 years ago.

 

Yes, there are some seven billion or so. If some disaster were to wipe out 99,9% of the human race, there would still be 7 million left, way too many to be considered an endangered species.

 

And we still have to explain why we have found traces of human habitation in Australia from around 40,000 - ?60,000 years ago

 

I am going with the Great Spaghetti monster and the Amazing draining of the collander.....lets call it oh 5000 years ago.....and of course the Great Spaghetti Monster created fossils and sedimentary rocks to fool the foolish humans who refuse to accept the wisdom of the Great Spaghetti monster.

 

It may be that ancient man was more able to cross oceans than we think. Must be, in fact, unless there is some supernatural explanation for humans having arrived there that long ago.

That timeline leaves 10-30 thousand years for humans in Africa to have invented boats and sailed to Australia. That should have been long enough.

I wonder why they waited for the land bridge to come to America? I don't suppose we'll ever know the answer to that one.

 

I find that fascinating- there is still so much we don't know about early human beings- that they were able to reach Australia- and Tasmania- suggests that they had some ocean going capabilities then.

 

Well 2000 is doable. I believe studies in the past seem to indicate all the cheetahs in Africa stem from 7 breeding pairs, and the ancestors of the American Indians may have been a total population of 6 people.

 

Humans didn't migrate to Siberia until much later than they went to Australia- the environment was fairly hostile- and there is a lot to suggest that they didn't use a 'land bridge' but some form of water transport earlier than we thought 20 years ago.

 

Really? That is a new one on me.

 

I want to change my answer... This was the time of Xenu... and the great soul harvesting purge on Earth (then teelak) for thetan conversion. Sure... same numbers and timeframe...

 

More interestingly - look up "Kow swamp people" and look at the shape of the skulls, then ask yourself - which branch of hominids were these people?

 

Yeah it was a study back in the day looking at why American Indians have that copper colored skin tone. I have not seen anything on it for years, so it is very possible modern genetic studies may have discounted it. But it was a fact that always stuck in my head.

 

This is sort of old news, and I always heard it was due to general effects from the Mt Toba eruption, around 74,000 years ago.

As to how humans got to Australia without trace you don't need oceangoing capabilities. They could have come by land but stayed along the coasts; most of the coasts between Australia and Africa are now underwater

That people were in the Western Hemisphere around 20 k years ago or before is becoming more and more accepted, though it's still rather controversial. Some new theories say they may have come from Europe along the Atlantic edge of the Laurentian Glacier, or even via the Pacific. The Pacific Oceanians were culturally late stone age, yet they settled nearly every island in the Pacific. Given that accomplishment it seems odd that they never made it all the way across.

One thing I've always wondered about. Has anyone ever theorized that humans lived ON the glaciers in the Ice Age? I mean in the interior sections. I guess that's the wrong type of reasoning tho; first you find evidence that some did then you explain it. But if they did, what kind of evidence would they leave?

 

At least Ask.com maintains that most First Americans AREN'T copper colored

http://answers.yahoo.com/question/index?qid=20120525182911AA9NiN7

And I've heard this other places too. One is, oddly enough, from stories of the Beothuk of Newfoundland, who liked to paint themselves completely red. I say oddly because the Beothuk are one of the main bases of the theory that some Amerinds may have come from Europe, as they had customs and a technology that reminded many anthropologists of paleolithic Europe, though it's hard to credit they wouldn't have just assimilated after 10 millenia. Unfortunately, the last one died in 1867 so we'll never know.

 

many of the natives in the Precambrian shield areas of Canada painted themselves completely red

 

It explains why humans show massive inbreeding in our DNA.

 

What we are required to think depends on what fad theory dominates the narrow-minded conformists in anthropology. I can't even post my theory because of the way we are dominated by unrealistic theories of equality. The Indians were originally driven out of the inhabitable lands and wound up in Siberia, so let's pretend they were "victims," not fugitives. Others of a similar species were driven into Southeast Asia and Polynesia.

The Northern tribes lucked out in getting to a North American paradise, where they were driven into the Amazon by the next wave of fugitives. So you can find the real First Americans among the cannibals.

 

Yes. I've read that the population of modern humans went through at least one bottleneck where the number of total breeding pairs might have been 100 or so. The most common location suggested is coastal caves in South Africa, and the genetic evidence gives a time frame.

Also, for what it's worth, primates generally have a lousy survival record, with all hominids but one going extinct (as many as six may have lived at the same time). Yeah, all these ancestors had big brains (big skulls, anyway), and may have been pretty smart, but intelligence doesn't defeat predators, technology does. The necessary level of techology really didn't exist until the invention of science -- the bubonic plague nearly exterminated us. It was the replacement of religion with science, about 300 years ago, that really set humanity onto the path of excessive overbreeding. I seriously doubt that technology will find a cure to that pattern before it's too late.

 

Hmmm- in the western world reproduction is now even. Technology allows for humans to prevent 'overbreeding' but the advances of sanitation and vaccines have led to over reproduction in societies until families become economically secure.

 

Just a note...it seems at least a few of these hominids did not become extinct, but instead interbred with each other and created us.

 

I strongly suspect that there were already small human populations outside of Africa 70,000 years ago. These isolated groups may have made a greater genetic contribution to later groups than the ones from Africa. In any case, quite a lot of evolutionary change can happen over 70,000 years.

I am sure there are some anthropologists who, do social-political reasons, desperately either want to either believe homosapiens left Africa much more recently, or alternatively much farther back in time. The actual reality is likely more complicated, likely there was more than one wave out of Africa. Since the genetic diversity within Africa is generally much greater than the entire human population outside, it either suggests that there was one primary wave, or that a stable human population was able to evolve somewhere outside Africa 40,000 years ago.