I though I'd start a new thread as to not totally clutter up the other.

I've been busy myself recently but I've watched the first part of that 'doco' and I have a bone or two to pick with it. Of course I accept that I've only seen half of it so far.

The huge jump (stated at about 18:45) that it has to be 'internal' and not driven by 'adaption to the environment' is made but not substantiated.
Nothing said is incompatable with the notion of natural selection.
So far the documentary has made some rather important ommisions.

Whilst a big deal is made of weakness in the 'savanah hypothesis' no mention is made of other natural selection driven 'hypothesis' e.g substantial work relating to 'branch walking' in other primates.

That whilst natural selection is indeed very important other factors such as sexual selection and genetic drift also affect evolution.

The change in shape of the sphenoid bone is referred to as a 'great' mutation, I assume this means they are viewing it as a macromutation (not to be confused with micro/macro evolution). Whilst in terms of the phenotype the change in bone shape and orientation appears large it does not mean a large genetic change has taken place. Very often a small genetic change (i.e a small mutation) has it's effect on the phenotype 'amplified' by the way in which embryos develop.
Once such a mutation occurs it will then be acted on by natural selection, so if being upright did give an advantage selection pressures would increase the frequency of the 'flexed' spheniod form.

The othodontist bit about increased jaw/theeth misalinment is interesting and I would be interested to find out more, however please note that it to can be interpreted in the light of natural selection. Modern othodentistry has removed any selection mechanism that may in the past reduced the incidence of these problems.
My family has a history of being 'short sighted' (luckily I'm only slightly affected), the number of glasses wearers in the whole population looks to be increasing. Does this mean an internal mechanism is driving humantity forward to myopia? Or that with the availability of glasses sight problems no longer reduce 'fittness' in the way they would have done?


I'll watch the next bit this weekend and try to root around abit on tinternet.

I have occasionally wondered how technology is affecting the evolution of mankind. As WM pointed out, we have, for the most part, eliminated most physical selection pressures (ie eyesight, deformed limbs, some childhood cancers, most fatal childhood diseases, etc.). People who would have had little to no opportunity to breed in the past can now live long and fruitfully reproductive lives.

--Outlaw.

I think the big technological change so far has been agriculture. Cars, mobile phones, computer etc have only really started to have an impact on most of the world in the last generation. Not much time to make a difference!

quote:

Originally posted by Aaron_GT:
I think the big technological change so far has been agriculture. Cars, mobile phones, computer etc have only really started to have an impact on most of the world in the last generation. Not much time to make a difference!

I wasn't very specific when I said technology. I'm talking about the medical advances that allow people to reproduce that, in the past, would never have had the chance. Of course you are correct in that has been a short time, but, the effect can already be seen in the fact that there are more female haemophiliacs (carried on the x chromosome) now than in the past because more male haemophiliacs are surviving to reproduce.

--Outlaw.

The title to this thread sounds like the name of some gay french art house film

quote:

Originally posted by Outlaw---:

quote:

Originally posted by Aaron_GT:
I think the big technological change so far has been agriculture. Cars, mobile phones, computer etc have only really started to have an impact on most of the world in the last generation. Not much time to make a difference!

I wasn't very specific when I said technology. I'm talking about the medical advances that allow people to reproduce that, in the past, would never have had the chance. Of course you are correct in that has been a short time, but, the effect can already be seen in the fact that there are more female haemophiliacs (carried on the x chromosome) now than in the past because more male haemophiliacs are surviving to reproduce.

--Outlaw.

I'm sure its a quote (but I can't remember by whom) and not my original thought but Humans are the first organism to escape the tyrany of their genes. For some time now our 'evolution' has been cultural not biological. Edit: Or maybe more cultural than biological depending on how far back 'some time' is.

To Aaron bang on about agriculture, both biologically significant (lactose tolerance etc) and culturally (without farming we wouldn't have cities, extensive ruling classes, organised religion in it's modern form etc).

OK I've just watched the second part of the film.
Whilst there is lots of cool and interesting stuff, the science is weak.

For instance the idea that there are just 2 competing thoeries (the Bejing bit) Out of Africa (single exodus) vs multiple emergance of H. sapiens is an over simplification. In fact they represent the two ends of the theories. There is alot in between. Genetic evidence (how unvaried our genomes are) does seem to make the simultanious emergence of sapiens in multiple locations unlikely. However even if it is the case it does not lead automatically to a non-adaptive mechanism.

There is also a mistake in the film I would like to draw attention to, the film refers to the great cultural revolution that came with the emergence of H.sapiens. In fact there is a large gap between the first sapien fossils and cave painting, more complex tool etc. The sudden cultural revolution that did occur is know as 'The Great Leap Forward' and is a facinating enigma.

BTW I know it seems I'm just trying to rip into the film. It is true that many 'popular' science programmes are guilty of similar whoolly thinking and oversimplification. The problem is the film is based on a very big/wild/novel premiss, things like that need backing up if they want to be thought of as serious.

Last moan , and this one is relevent to lots of programmes, books etc.
The section with the African Bushman people falls into the trap of viewing them as more primative than the rest of humanity, the idea that their language will be closer to the 'first language'. It may be but, the African Bushman people are just as much modern humans as everyonelse, those women are no closer related to an early human than you or I. I mean that literally, by the time their family tree went back to an early 'homo' it would have joined with everyones tree. We would be looking at the common ancestor of us all, our shared great great great.......great grand parent!

quote:

Originally posted by Outlaw---:
As WM pointed out, we have, for the most part, eliminated most physical selection pressures

Despite being a very common sentiment, that is actually wrong. What technology has done, is changing the selection pressure. We are no longer selected for being strong, free of certain diseases etc, but we are still subject to selection. The speed of modern vehicles makes those with slower reflexes at risk. The modern society makes people without technical insight at a disadvantage, in a world of quick and easy communication, there's a strong selection for physical beauty etc.

Not better, not worse, just different.

We also tend to forget that the Western world is not the full picture. "Classical" selection pressure is very much alive and well in third world countries.

quote:

Originally posted by Whirlin_merlin:
The sudden cultural revolution that did occur is know as 'The Great Leap Forward' and is a facinating enigma.!

The 'The Great Leap Forward' is another of the "so self evident no-one looks at the evidence" type of phenomena. In reality, the "great leap" was a series of small leaps over half a million years. When putting up all the little finds that indicate progress and examine them critically, the notion that that an ape-man one day woke up and found himself human goes away.

I have seen a bit of clips from the program, and it's very much "yesteryears science", presenting 10-15 year old intriguing (but dated) theories as modern science.

Hi Whirlin,

once again, I am very busy these days. I'll try to reply when I can.

quote:

Originally posted by Whirlin_merlin:
OK I've just watched the second part of the film.
Whilst there is lots of cool and interesting stuff, the science is weak.

The program is just a teaser and meant for the general public, at least those with an interest in the subject. I saw this program as a springboard to inspire further study, which I've done.

As you already know, my chosen focus is cognitive linguistics and the many sub-fields within. The sphenoid is most interesting to me since speech wouldn't be possible without the evolutionary changes it has gone through.

quote:

Originally posted by Whirlin_merlin:
For instance the idea that there are just 2 competing thoeries (the Bejing bit) Out of Africa (single exodus) vs multiple emergance of H. sapiens is an over simplification.

It would be but I didn't get that from the program. It seemed to me that those two theories were chosen for their popularity. I think it's important to realize that the information is limited to the length and budget of the program rather than the program being limited to information. Again, it's a springboard.

quote:

Originally posted by Whirlin_merlin:
Genetic evidence (how unvaried our genomes are) does seem to make the simultanious emergence of sapiens in multiple locations unlikely.

Interesting statement. Just how varied or unvaried must our genes be to allow simulteneous emergences in multiple locations? A micro-view would reveal many variations while the macro-view reveals little to null.

quote:

Originally posted by Whirlin_merlin:
There is also a mistake in the film I would like to draw attention to, the film refers to the great cultural revolution that came with the emergence of H.sapiens. In fact there is a large gap between the first sapien fossils and cave painting, more complex tool etc. The sudden cultural revolution that did occur is know as 'The Great Leap Forward' and is a facinating enigma.

Which raises a question; does this gap represent a pause in our development or the current available data? Either choice would be an assumption. Ironically, we don't have enough data to claim a gap even exists.

quote:

Originally posted by Whirlin_merlin:
BTW I know it seems I'm just trying to rip into the film. It is true that many 'popular' science programmes are guilty of similar whoolly thinking and oversimplification. The problem is the film is based on a very big/wild/novel premiss, things like that need backing up if they want to be thought of as serious.

Interestingly, I found this "very big/wild/novel premiss" made a lot more sense than other theories. Of course, my thoughts were not based on the merits of the program alone. The reason I didn't get into this before was simply that I just don't have the time. I didn't save all my sources because I didn't think of starting a thread on this. My studies are work related for my own development.

quote:

Originally posted by Whirlin_merlin:
Last moan , and this one is relevent to lots of programmes, books etc.
The section with the African Bushman people falls into the trap of viewing them as more primative than the rest of humanity, the idea that their language will be closer to the 'first language'.

I didn't get that from the program. Any racism and prejudice will come from a certain audience, not the program itself. We can't start omitting evidence and points in order to avoid the concepts and perceptions of the ignorant. PC does not belong in science.

quote:

Originally posted by Whirlin_merlin:
It may be but, the African Bushman people are just as much modern humans as everyonelse, those women are no closer related to an early human than you or I. I mean that literally, by the time their family tree went back to an early 'homo' it would have joined with everyones tree. We would be looking at the common ancestor of us all, our shared great great great.......great grand parent!

I'm sure you didn't mean it this way but it sounds like you are saying there's a good chance that they are 'less evolved' which supports my previous point about being PC in science. PC is anti-scientific.

I think many will get the impression that the program is trying to say that the environment has nothing to do with it. In fact, the program used the Savanna theory simply because of its popularity and the even showed a scientist stating that our evolution is totally subject to environment. In my opinion, that's silly.

Sure the environment plays a major part but it is not the only part. Africans are dark partially because they need to be to cope with their environment. The same goes for their facial features. I am what I am because of where my ancestors came from. In many ways, I'm built for cold weather. I actually become ill in hot weather. I rock in sub-zero temperature.

It seems to me that somewhere down the line, the dna governing the flexion of the sphenoid mutated. All mammals' sphenoids have gone through evolutionary flexion but nothing compared to ours. We could label this human phenomenon as 'hyper-flexion'.

We come from the same root as apes but are today very different. I often hear people say things like "We share 98% dna with apes". To me, that means we are not similar. Take a journey of 1,000 miles in a straight line to a designated destination. If you are just 1 degree off in direction, then your destination won't be in sight. The differences of 2% in the genes of humans and apes are much, much greater than the 1 degree.

It seems this 'hyper-flexion of the sphenoid created a new line. The most interesting part is the apparent memory within our genes. Our sphenoids start out as they did 40 million years ago but between the 7th and 8th week of life, they hyper-flex. The same happens in all mammals but without the hyper-flexion. Of course, the sphenoid alone does not represent what we've become but what we have become would not be possible without the hyper-flexion. The sphenoid is 'all dat and bag'o chips'. Our brains, our bipedalism, stereoscopic vision, and our complex language, and therefore society, would not have developed without the flexion of the sphenoid.

That's all for now. Sorry if my replies seem rather short, but I got lots to do tonight.

Fritz

quote:

Originally posted by Friendly_flyer:
The 'The Great Leap Forward' is another of the "so self evident no-one looks at the evidence" type of phenomena. In reality, the "great leap" was a series of small leaps over half a million years. When putting up all the little finds that indicate progress and examine them critically, the notion that that an ape-man one day woke up and found himself human goes away.

Until there's enough evidence to support 'The Great Leap Forward', it's nothing more than a hypothesis. I wouldn't even call it a theory. That's not to negate the possibility but rather to keep in mind the lack of supporting evidence.

quote:

Originally posted by Friendly_flyer:
I have seen a bit of clips from the program, and it's very much "yesteryears science", presenting 10-15 year old intriguing (but dated) theories as modern science.

I'm surprised Peter. I wouldn't even comment on 'bits of clips'. You might want to watch it considering the 'star' scientist had done further researched for over 10 years (at the time of the program) to support ideas she had already formally submitted to her peers.

Just to keep things clear;

The program does not deny our evolution having relevancy to the environment.

The program denies our evolution is subject only to the environment.

Let's not polarize this one.

quote:

Originally posted by Pirschjaeger:
The program denies our evolution is subject only to the environment.

I suppose that's a question of how you define environment.

As is defined in the Savanna theory.

quote:

Originally posted by Friendly_flyer:
Despite being a very common sentiment, that is actually wrong. What technology has done, is changing the selection pressure. We are no longer selected for being strong, free of certain diseases etc, but we are still subject to selection. The speed of modern vehicles makes those with slower reflexes at risk. The modern society makes people without technical insight at a disadvantage, in a world of quick and easy communication, there's a strong selection for physical beauty etc.

Not better, not worse, just different.

Which is why I qualified my statement with, "for the most part".

While it is true that larger relative velocities make it more difficult to avoid collisions, I believe that modern safety features along with truly amazing first response trauma teams more than make up for it.

I fail to see how modern society has put anyone without a technical insight at a breeding disadvantage. In fact, those groups have the highest birth rates.

The male sex drive and female low self esteem can quickly overcome the "strong selection for physical beauty". Easy access to alcohol doesn't hurt either.

The third world is definitely closer to the "good old days" of natural selection but slowly and surely advances are reaching out and touching those parts of the globe also.

Small pox has been virtually eradicated worldwide and IIRC, polio is on the decline also. HIV is a relative newcomer with dire consequences but that one will be a bit easier to conquer as education can almost completely eliminate its spread.

--Outlaw.

There are some suggestions that the genes are changing more now (i.e last 5000 years) than before, based on extracted DNA. Still controversial. It makes sense in that humans were hunter gatherers for 10s of thousands of years and agriculture is 'new'.