Erectus Shrinking

[uniface]

So if a group moves OOA and stops in, say, India for a while they would adjust to conditions in India. Yes.

Then, the same group or a sub-unit moves north to Afghanistan and adapts to those conditions. It seems that even in a relatively short span of time the original group could fracture many times as they adapt to different climates.

Is that about it?

Whether it is or not I can't say.

But if this is supposed to involve adaptions more fundamental than improved clothing and survival strategies, it certainly is a good working example of Lysenko-ism.

[Digit]

Is it? Or is it a case of you rejecting an idea without offering an alternative to the various groups of homonids that exist/have existed?

Roy.

[Minimalist]

Dig, wouldn't you consider human culture to have had some impact on strict Darwinism, though. HE, at least, provides evidence of seriously injured individuals being tended while they were incapacitated judging from healed fractures. Whether or not this was a true cultural mechanism is debatable.... might be just some stirring of a consciousness within the group but a lion is a pack hunter too and if one is injured in the hunt it lives or dies on its own. As Rokcet said, there seems to be more than one thing going on here.

[Digit]

I don't see that it matters Min.
Either Homo has a single point of origin, where ever, or we have to assume that there has been two or more separate and distant 'creations'. Which would mean that what is currently classified as Homo is unlikely to be correct.
Let us assume that Asiatics are in no way related to Africans, that they arose not from a common ancestor, but from two entirely separate events. Interbreeding would seem to be unlikely, though they might look alike, genetically they would be unlikely to be compatable. Thus I have to assume an origin from common stock.
So far more hominids have been found in Africa than elsewhere, that would suggest that Africa is the ancestral home. New discoveries might well overturn that of course.
So let us asuume an African origin. Can you see their decendents, after hundreds of thousands of years in Asia still being unchanged by NS selection due to their different environment?
I can not.
From Darwin we could well see a genetically stable population in Africa that would suddenly undergo all sorts of changes to accomodate them to their new environment, in fact, from Darwin, I would expect it!
The African population that remained in the ancestral homeland would likely have much less need to change, untill they did migrate, then change they must IMO.

Roy.

[Minimalist]

Okay, let's say the point of origin WAS Africa (which seems reasonable) and that there is more of a need for the groups which moved OOA to adapt to new conditions than the ones who stayed behind. I agree that multiple points of origin seems mathematically improbable.

However, the traditional view is that it was the ones who remained in Africa who generated the new "species." I.e., HSS arose in Africa after HE and also spread all over the world. My gut reaction is to agree with you, that groups which traveled furthest and met the most dramatic change in conditions would have done the most adapting (with a growing culture impacting around the edges) . But that means either that the "traditional view" is wrong or there was significant change going on in Africa as well?


Call it instinct if you like but I think that Rokcet's "all of the above" suggestion has some merit. However, if humans retained the ability to interbreed ( meaning that these "species" were not really separate) then it would facilitate the process. We really need to find some HE dna.

[Digit]

We really need to find some HE dna.

Don't we! It would seem on current evidence that numerous hominids arose in Africa but ultimately failed, if so that would leave, possibly, Erectus to carry the flame and followed, possibly, by HSS. That would leave pretty much all Asiatic, Bush Men? Australian and southern Asiatic coastal groups, which still retain their distinctive appearance, as a direct line from Erectus. That would seem, if correct, to make the human race mainly Erectus with just Eurasia as HSS, using present nomenclature.
Now all we need is to find that HSS arose in Asia/Eurasia and it will hit the fan 'cos then we are all Erectus sub variants and many will probably shoot themselves!
Erectus DNA would solve that, hopefully.
The existance of the X DNA, plus HSN, lends strong support to the idea of much development taking place away from Africa, which Darwinism would require, and I suspect that there are many surprises still to come.
The idea of Erectus colonising the world solves a lot of the time line difficulties as he so much more time available to do it.

Roy.

[Minimalist]

I've yet to see anyone suggest that people ever went "back to Africa" although, of course there is no reason why migration could not have gone in both directions.....or by boat!

[Digit]

The earliest HSS is, AFAIK, from Ethiopia Min, effectively right on the borders of Africa and Asia. So who knows.
One of the reasons I suspect that there is a large element of HE in us is the skin colour problem. People are supposed to have reached Australia not more than 50K years ago, and they are black. Therefore it is reasonable to assume that their ancestors were also black, now the question is how long did it take them to get from Africa? to Oz.
Let us assume 10K years ago, therefore the yellow/white gene must be more recent than 60K years. Being a genetic change, mathematically it must have arisen in a single individual. Europeans have been white for at least 10/15K years, thus the white gene must have come from Erectus or spread like a forest fire through out Europe from a second and later source.
This raises another problem. If Asiatics are HSS and Europeans are HSS we now need TWO genetic changes to have occurred in next to no time!
If you exclude Erectus there simply does not appear to have been sufficient time.
I would add that Bushmen are yellow, just to stir the pot a little more.

Roy.

[Minimalist]

I agree.

And the Neanderthals had the red hair and blue eyes and c 28,000 bc is the last possible date for them. So, did HSS and HNS develop the same mutation independently? What are the odds of that, I wonder?

[Digit]

Pretty damn small IMO Min. The standard timelines simply don't hold up.
I've been saving this.....

http://www.handprint.com/LS/ANC/evol.html

it shows no connection between HE and HSS. Therefore the official line must run thus...
HE leaves Africa 1.8MY? ago and colonises the planet.
700KY ago HSS leaves Africa and colonises the planet completely, eliminating all genetic traces of HE in doing so.
The problems I have with that are this.
Firstly why leave Africa? It was never over crowded and leaving meant a water crossing. The full extent of HE's efforts are unknown to us due to geological, sea level and ice cap changes, but he had a lot more time than HSS has had.
Aboriginies are either HE or HSS, if HSS they moved damned quick, which suggests by water. So if HSS left by water then the coastal route via India etc is the logical one.
According to genetic tracers that is indeed the route taken, apparently at the time the Arabian peninsular was well watered near the coast, that being so we need to look for yet another migration, across the northern Nile, cos from the coastal route deep into Asia requires yet another gallop.
The 70K time line clashes with Toba, but it's worth remembering that the north-east and the east were not affected by the fall out, so Asiatic HEs would not have been affected.
Further there is now evidence that man survived the fall out in India, which has to mean he was there before Toba, which I believe is now dated 74KYs ago.
I get more confused.

Roy.

[Rokcet Scientist]

Aboriginies are either HE or HSS

There you go again creating problems for yourself, Roy: it is not either/or! It is both! HS(S), on his long trek OOA, in any direction, caught up with HE variations that had gone there long before them, and they hybridized! The Aboriginals, the Papua and the Bushmen are prime examples, imo.

BUT WE ARE HYBRID HE/HS(S) TOO, only not so recognisable. I think we should let that sink in.

And of course add a dash of HN to the cocktail. Unless you're of the school that considers HN a latter evolution of HE, because he then is already in the mix of course.

[Digit]

That is what I suspect RS, but without some proof I am not prepared to nail my colours to any particular mast. Mainly what I was attempting is to show some of the more obvious difficulties with the Club viewpoint.

Roy.

[Minimalist]

I get more confused.

See what happens when you think things through?

[Digit]

Dirty work I know Min but sombody has got to do it.

Roy.

[Minimalist]

I know that it isn't a crowded field.