Upright Humans Came Down From Trees, Not Up From Ground

I thought this was a fairly old idea. I remember it being mooted as a theory back in the 70's. Seems sensible.

I would be in favour of a more complex interaction between different humans in the past. The out of africa thing for me has too many holes. It's too pat and a tad too "fashion" driven for me. Genetics is a helluva tool and has told us much, but I think science at the moment is too reliant on it for a source of origins and timescales. Especially given the dearth of fossil remains and viable DNA that can be extracted from same.

Now I do believe humans as a species originated in africa. But I believe that this was in successive waves and later hominids interacted with and reproduced with earlier hominids that they came across in their travels. Specifically Erectus and in the case of Europe Neandertals. I dont favour the pure multiregional hypotheses, where its all about the local. I would think of it broadly as Erectus leaves africa. Moves all over the globe(except the new world). Evolution of hominids continues in Africa, but it also continues in the rest of the world where erectus exists. It seems strange to me that such evolution should be very fast paced in Africa, yet we're to believe that Erectus was pickled in aspic elsewhere even with local adaptation pressures? I don't buy it. Plus as Neandertals in Europe prove erectus did evolve into later forms. Whose to say there's not a similar erectus evolution in asia say. One we've not seen yet. Flores man(another erectus) shows how fluid and local this can be.

Then early not quite sapiens evolves in africa and like an aussie back packer decides to go walkabout. They move into area where erectus and it's descendants live. They get jiggy with it and the populations mix and the earlier gets brought into the later. Other cultural pressures do in the rest of the erectus/neandertals(and some of the moderns too). That makes far more practical sense to me than the current idea, which is erectus stays largely the same for a million years. We come along and completely replace them in those areas with no interaction or gene mix. It just doesn't fit for me.

Even the genetic evidence as outlined in that wiki entry suggests some local continuity of genes, not found in other locales that are significantly older than the 200,000 yr old migration of (nearly) modern humans. That makes no sense if we all stem from that population. We didn't lick those markers off a stone.

Plus in the example I gave on the other thread, http://www.boards.ie/vbulletin/showpost.php?p=61812247&postcount=10 DNA can leave big holes in our understanding of whats going on.

OK I'm of european stock. Lets say I marry an african lassie and we have two sons. One of them marries a japanese woman and the other marries a south american woman from the high andes. If we look at their kids mitichondrian DNA it'll show that they're either Japanese or Andean indian. No trace of African or European. If you look at their Y chromosome DNA they'll look like Europeans. In both cases No trace of African DNA at all, yet they would share the genetic heritage of the oldest people on the planet. That's just over 3 generations, yet we're supposed to believe that over 100's of 1000's generations we're not missing out some huge chunks of what is going on? I dont buy it.

Oh yea way before. Erectus was fully adapted for upright walking and running. Analysis(of turkana boy) suggests that erectus was very fast as a runner. Faster than modern humans. Make the Usain Bolt lad look like a pensioner. They were a serious apex predator it seems. Would be amazing to go back in time and see one in action. Magnificent looking buggers.

There are so many unusual things happening at times, even with "us" homo sapiens. Around 40,000 yrs ago a lot of things changed, seemingly overnight. We looked the same in the bones, diet was the same(locally) stone tools didn't change much, but things were afoot. We started to live longer for a start. Much longer. Before that point 30 would be old, 40 would be ancient(though at leats one Neandertal was 40). Then we started to live to 60 for no apparent reason. Art and culture exploded. Again we looked the same in the bones and so far nada has been found in the genes to explain it.

40,000 years ago is way before farming though. We're in middle palaeolithic/stone age times here. Oh doubtless there was some environmental change involved, but what was it? It seemed to happen pretty much worldwide very rapidly. There had been art before, but it was sporadic and very small scale(geometric marks in small blocks of red ochre).




As for diet, yes I agree with you farming increases the quantity, but it can be argued decreases the quality for the individual. Early farmers are not as robust as late hunter gatherers and the dietary changes can require adaptations by the body too when novel proteins are brought into the diet(gluten lactose etc).

What is amazing about modern humans is that we're the odd ones out. If you look at a neandertal you can see features that go all the way back through earlier hominids. Features we don't have. Massive nasal cavities, brow ridges, to name but two and we have features they don't have like high vaulted skulls* flat faces, chins and a few others. Most of our ancestors were far more robust too. I dont care how big a guy you are, or how strong you are, stepping into a cage fight with an erectus and defo a neandertal would not go well for you. "Here bookie, I know the other lad is world MMA champ but my money's on the ginger lad with no chin. Ten seconds down in the first round"

If you had a party and gathered all the major versions of our ancestors, they would be looking at us as the weird ones, more than the other way around. We would be the odd man out as it were. Which is interesting as it suggests a set of evolutionary pressures quite a bit different to our cousins.

Thread for another day maybe.:)



*not just to fit our brains in either as the largest homind brain size wise belonged to a Neandertal.