"Visual brains" doomed the Neanderthals

Adam Khor

Seems that everything from rabbits to brains wanted to "doom" Neanderthals back in the day...

http://news.yahoo.com/neanderthals-doomed-vision-centered-brains-002516901.html

Wibbs

As I reckoned in the other thread...

it's an interesting idea alright. They certainly had much more grey matter at the back for processing vision and had the largest eyes of any human. The latitude notion even fits with moderns as today Europeans have the largest eyes on average. I don't think our visual cortex is any bigger though. In the Neandertal case I'd add that maybe they had such big eyes etc because they were more likely to be ambush hunting in forest, or even (personal notion alert) they were often hunting at dawn/dusk as a strategy. That might add another stress on them on top of our arrival if the forests were turning to grasslands where more long range hunting was then in play. Something they weren't suited to, but we were. That would also explain why "classic" Neandertals didn't seem to have throwing spears, though their ancestors homo heidelbergensis had. Maybe if we had shown up and it was heidelbergensis we encountered things may have turned out differently?

The only odd thing re their eyes is that they've been found in quite southern latitudes in the middle east and they kept these big eyes. In Israel we lived around each other in the same areas, cheek by jowl. That's where the genetics seem to show we got jiggy with each other*. Maybe this backs my mad notion that their big eyes were for dawn/dusk hunting? It might explain also why we could hang out together as we were using slightly different hunting strategies so didn't see each other as competitors.

Do you know what gets me of late AK? I'm beginning to take another angle... Not so much what they were doing, but what changed with us. I mean 100,000 years ago we were hanging out with them in the middle east using the same tools, doing pretty much the same thing with our smaller eyes and apparently superior brains and having kids with each other. In a glorified African environment. We moderns weren't exactly pushing the envelope. Erectus had been way more adventurous. The ice crept in and we legged it back home to Africa. They stayed. Fast forward around 60,000 years and this time we leave Africa and change the maps. Don't appear to be put off by ice or Neandertals or anything else. Don't appear to have got it on with them either. That suggests a huge mental shift in us. So what happened to us, modern humans in Africa in that time. Personally I don't buy the 100,000 year old South African "oh look scratches on ochre" deal at all. I doubt both the dating and the interpretation. It's too much of an outlier. Something really fundemental changed modern humans into what became us

Adam Khor

Capt'n Midnight

Wibbs wrote: »

100,000 years ago we were hanging out with them in the middle east using the same tools, doing pretty much the same thing
...
Something really fundemental changed modern humans into what became us

If we had a 0.01% advantage and take a 17 year generation then over 90,000 years the populations would be 200:1

Of course even a small advantage in numbers would be enough, especially when there is a whole convener line of replacements coming out of Africa

Actually if there are enough of us continually coming out of Africa we could displace the Neanderthals by attrition , like the battles of WWI with the Yanks replenishing the ranks later on.


While there are ethical issues out the wazoo, one can't help be curious of what would happen if we were to fertilize a human egg with a full set of Neanderthal DNA ( cheap slaves for all - to - terraformers )

Wibbs

Capt'n Midnight wrote: »

If we had a 0.01% advantage and take a 17 year generation then over 90,000 years the populations would be 200:1

Of course even a small advantage in numbers would be enough, especially when there is a whole convener line of replacements coming out of Africa

Oh defo CM. Lately I've been thinking that the "why did they die out?" may be the sideshow to the real question(s), IE why did we win and what changed in us between us living with them in the ME 100,000 years ago and us coming into Europe 40,000 years ago? Something changed and changed radically. The ME/Levant when we hung around together was very "African" in nature. We had been already around for around 100,000 years before this point and hadn't shown much in the way of innovation or indeed wanderlust beyond our safe zones. We made it to the Levant precisely because at the time it was more of the same that we were used to in Africa. Interestingly Neandertals had survived in Eurasia for 200,000 years in highly fluctuating environmental conditions. In that regard and at that point they look like they were the more adaptable. At that very time they were in the Africa like Levant, they were also hanging out much further north in entirely different environments. That seemed to be a no no for us.

So we live together and have enough kids together to leave a genetic impression to this day. Our toolkits were identical in nature(Levallois and Mousterian type stuff), IIRC we ate pretty much the same stuff. We tended to go on slightly longer foraging trips, but we're talking miles here, not huge distances. Culturally we seem to have been very similar too. There was a geehair(tm) between us.

Then the climate changed in the area. It got colder and the first tentative steps modern humans out of Africa took were halted and we retreated back. "run away, run away!!". The other guys adapted and stayed on in Europe as before. So far so good.

Fast forward 50,000 years and we leave again, only this time it's very different. Cold? I laugh at your steeenking cold. New foods? Bah serve it up pal. We also have the beginnings of new toolkits and cultural differences and that starts to really accelerate. We were a very different proposition. We had the wanderlust and the balls and brains and adaptability to survive and thrive in new environments. This time we get as far as Australia within a few hundred years, we get as far as the UK within a thousand or so. We became as different to our 100,000 years ago ancestors as we were to Neandertals.

In areas where we seem to have shared the space that's different this time too. 100,000 years ago we were living in the same kind of shelters and area levels as each other. This time we take the high ground, the Neandertals the low. We seem to establish a them and us mindset. The genetics also show this. So far no European Neandertal DNA from that time has been found in modern people. Maybe when we have enough raw data we'll find it and find us in them, but for the moment...

So what the hell happened in that gap that changed us so much? I know we started to live longer for some reason around 40,000 years ago, but the "spark" of real change seems to have happened in that pretty hidden period between say 90,000 years ago and 50,000 years ago. Sure there are the 100,000 year old sites in South Africa with patterned scratches on ochre and the like and possible sea shell necklaces, but personally I don't quite buy into them. I dunno why. I have a feeling the dating is off in the ochre site and the "beads" don't look very manmade to me. Walk any beach today and you'll see similar shells perforated by wear and tear.

steddyeddy

Wibbs wrote: »

Oh defo CM. Lately I've been thinking that the "why did they die out?" may be the sideshow to the real question(s), IE why did we win and what changed in us between us living with them in the ME 100,000 years ago and us coming into Europe 40,000 years ago? Something changed and changed radically. The ME/Levant when we hung around together was very "African" in nature. We had been already around for around 100,000 years before this point and hadn't shown much in the way of innovation or indeed wanderlust beyond our safe zones. We made it to the Levant precisely because at the time it was more of the same that we were used to in Africa. Interestingly Neandertals had survived in Eurasia for 200,000 years in highly fluctuating environmental conditions. In that regard and at that point they look like they were the more adaptable. At that very time they were in the Africa like Levant, they were also hanging out much further north in entirely different environments. That seemed to be a no no for us.

So we live together and have enough kids together to leave a genetic impression to this day. Our toolkits were identical in nature(Levallois and Mousterian type stuff), IIRC we ate pretty much the same stuff. We tended to go on slightly longer foraging trips, but we're talking miles here, not huge distances. Culturally we seem to have been very similar too. There was a geehair(tm) between us.

Then the climate changed in the area. It got colder and the first tentative steps modern humans out of Africa took were halted and we retreated back. "run away, run away!!". The other guys adapted and stayed on in Europe as before. So far so good.

Fast forward 50,000 years and we leave again, only this time it's very different. Cold? I laugh at your steeenking cold. New foods? Bah serve it up pal. We also have the beginnings of new toolkits and cultural differences and that starts to really accelerate. We were a very different proposition. We had the wanderlust and the balls and brains and adaptability to survive and thrive in new environments. This time we get as far as Australia within a few hundred years, we get as far as the UK within a thousand or so. We became as different to our 100,000 years ago ancestors as we were to Neandertals.

In areas where we seem to have shared the space that's different this time too. 100,000 years ago we were living in the same kind of shelters and area levels as each other. This time we take the high ground, the Neandertals the low. We seem to establish a them and us mindset. The genetics also show this. So far no European Neandertal DNA from that time has been found in modern people. Maybe when we have enough raw data we'll find it and find us in them, but for the moment...

So what the hell happened in that gap that changed us so much? I know we started to live longer for some reason around 40,000 years ago, but the "spark" of real change seems to have happened in that pretty hidden period between say 90,000 years ago and 50,000 years ago. Sure there are the 100,000 year old sites in South Africa with patterned scratches on ochre and the like and possible sea shell necklaces, but personally I don't quite buy into them. I dunno why. I have a feeling the dating is off in the ochre site and the "beads" don't look very manmade to me. Walk any beach today and you'll see similar shells perforated by wear and tear.

I would put that down to the same reason whales and elephants started to live longer, the menopause. The menopause allowed older women past reproductive age to focus on minding young children and play the "grandmother" role. This would have conveyed an evolutionary advantage on the tribe or herd and as a result the gene that conveys longevity past reproductive age would have flourished.

Wibbs

Aye but it happened in both genders(there are usually more old men as more women die in childbirth). Plus what was the selection pressure for this change, a selection pressure that hadn't come along in our previous near million year history as hominids? Why didn't this happen with Neandertals? Though IMHO they didn't die off as young as is thought.

steddyeddy

Wibbs wrote: »

Aye but it happened in both genders(there are usually more old men as more women die in childbirth). Plus what was the selection pressure for this change, a selection pressure that hadn't come along in our previous near million year history as hominids? Why didn't this happen with Neandertals? Though IMHO they didn't die off as young as is thought.

Well the andropause in men isn't as dramatic as the menopause and to some extent an active lifestyle negates it's worse symptoms.

As regards the selection of menopause, someone staying at home to mind children frees up more people to be hunter gathers.

Squeaky the Squirrel

They were all stocious.

Capt'n Midnight

During a dry spell humans can look for that lake that never dries out behind the mountain because your grandmother told you the story her mother told her about it


did Neanderthals have language ?

did they have smaller groups with less interaction and so less able to transfer information , could they have lost out simply because their "internet" was slower ?

Wibbs

Oh sure CM, but my angle is that we were the same at one point. We had small groups, presumably equally tooled up in language, using the same toolset as them and arguably even less adaptable as them, but something happened to us that didn't happen to them. Ditto for the Denisovans and others. Yes the explanation for our changes is obvious enough, but the why and how is lacking. What marked us out in that hidden period? Why did we start to live longer and they didn't, even though they had experienced and thrived in a multitude of varying environments for longer than we had?

Yitzhak Rabin

There was a fairly good documentary on nat geo today called 'Sex in the stone age'.

It explored the relationship between denisovan and neanderthals and moderns. I missed a lot of it as I kept getting interrupted, but it was very interesting.

Wibbs

Found it on Youtube.

Yitzhak Rabin

What did you make of the fact that the only place they found Denisovan DNA in current populations was in Papau New Guinea?

I always thought that Australian Aboriginals and Papua New Guineans would have been closely related, so unless they excluded Australians from the genetic study, it seemed unusual. Also very unusual that that they didn't find any Denisovan DNA on the mainland between Siberia and the Pacific?

Wibbs

Well they found one group of Aussies that had the genes. For me the pattern didn't strike me as too strange. When we left Africa in our Sapiens Mark II version, we ran along the coast of Asia pretty damned quickly and landed in Oz equally quickly and probably avoided those preexisting humans in the interior.

Then our second wave comes along, finds the coasts already lived in, thinks fcuk this for a game of soldiers and forges inland*. Then we bump into Denisovan folks(and maybe others) and get jiggy. Those lines then move out and go a slightly different route and end up in New Guinea and the like. A small group of these folks even get to OZ, which might explain why the earliest Aussies look more "modern" than some later Aussie populations. The latter showed up later with the suite of different human genes in tow. Plus we must always be mindful of looking at what genes happened to survive and then making assumptions from that. If we had a time machine and went back 10,000 years we might well find the current dispersal matches or we might find that a load of indicative lines have died out since then. As I'm sadly all too fond of pointing out if we were to go by genetics, we'd look at "Anglo Saxon" England and ask who da fuq where these Saxons?.

Them not being in the Bering sea type folks? Again Id say either the Siberian folks were among the first to run along the coast PDQ, or they came long after all the inter hominid shagging went on. Either they came too early to the party and went elsewhere or came too late for the party and went elsewhere..





* this is an aspect I always found interesting. The assumption that we wandered out of Africa into "virgin" lands. Biiiiig problem with that was with the exception of the Americas(and even there you never know), there were people already in every area we would have moved into. "We claim this for African humans!". *Murmuring from the back* "Ehhhh? Lads, we're standing over here FFS. BTW your sister looks good". "Oh yea, sorry. Yea she's single. Has a thing for pale guys with brow ridges and red hair. I know, I know, she loves the ginge. Don't judge me. We all have our crosses to bear.". "GTFO!, my brother likes the dark ladies with black hair. BTW I've got this great herb. Fancy a drink?". "Don't mind if I do oul son and if you think that drink is good, wait'll you have a go of this stuff".