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Agrippa
Friday, September 9th, 2005, 04:24 PM
Originally posted on Dodona by Melnorme:


http://www.nytimes.com/2005/09/08/science/08cnd-brain.html?ei=5094&en=7f83ee9b96d40611&hp=&ex=11 26238400&adxnnl=0&partner=homepage&adxnnlx=1126212523-Sy51vhmKhac0/YQeUBpASA&pagewanted=all

Researchers Say Human Brain Is Still Evolving

By NICHOLAS WADE
Published: September 8, 2005

Two genes involved in determining the size of the human brain have undergone substantial evolution in the last 60,000 years, researchers say, suggesting that the brain is still undergoing rapid evolution.

The discovery adds further weight to the view that human evolution is still a work in progress, since previous instances of recent genetic change have come to light in genes that defend against disease and confer the ability to digest milk in adulthood.

The new finding, reported by Bruce T. Lahn of the University of Chicago and colleagues in the journal Science, could raise controversy because of the genes' role in determining brain size. New versions of the genes, or alleles, as geneticists call them, appear to have spread because they enhanced the brain's function in some way, the report suggests, and they are more common in some populations than others.

But several experts strongly criticized this aspect of the finding, saying it was far from clear that the new alleles conferred any cognitive advantage or had spread for that reason. Many genes have more than one role in the body, and the new alleles could have been favored for some other reason, these experts said, such as if they increased resistance to disease.

Even if the new alleles should be shown to improve brain function, that would not necessarily mean that the populations where they are common have any brain-related advantage over those where they are rare. Different populations often take advantage of different alleles, which occur at random, to respond to the same evolutionary pressure , as has happened in the emergence of genetic defenses against malaria, which are somewhat different in Mediterranean and African populations. If the same is true of brain evolution, each population might have a different set of alleles for enhancing function, many of which remain to be discovered.

The Chicago researchers began their study with two genes, known as microcephalin and ASPM, that came to light because they are disabled in a disease called microcephaly. People with the condition are born with a brain that is much smaller than usual, often with a substantial shrinkage of the cerebral cortex that seems a throwback to when the human brain was a fraction of present size.

Last year Dr. Lahn, one of a select group of researchers supported by the Howard Hughes Medical Institute, showed that a group of 20 brain-associated genes, including microcephalin and ASPM, had evolved faster in the great ape lineage than in mice and rats. He concluded that these genes may have played important roles in the evolution of the human brain.

As part of this study, he noticed that microcephalin and ASPM had an unusual pattern of alleles. With each gene, one allele was much more common than all the others. He and his colleagues have now studied the worldwide distribution of the alleles by decoding the DNA of the two genes in many different populations.

They report that with microcephalin, a new allele arose about 37,000 years ago, although it could have appeared as early as 60,000 or as late as 14,000 years ago. Some 70 percent or more of people in most European and East Asian populations carry this allele of the gene, as do 100 percent of those in three South American Indian populations, but the allele is much rarer in most sub-Saharan Africans.

With the other gene, ASPM, a new allele emerged some time between 14,100 and 500 years ago, the researchers favoring a mid-way date of 5,800 years. The allele has attained a frequency of about 50 percent in populations of the Middle East and Europe, is less common in East Asia, and found at low frequency in some sub-Saharan Africa peoples.

The Chicago team suggests that the new microcephalin allele may have arisen in Eurasia or as the first modern humans emigrated from Africa some 50,000 years ago. They note that the ASPM allele emerged at about the same time as the spread of agriculture in the Middle East 10,000 years ago and the emergence of the civilizations of the Middle East some 5,000 years ago, but say any connection is not yet clear.

Dr. Lahn said there may be a dozen or so genes that affect the size of the brain, each making a small difference yet one that can be acted on by natural selection. "It's likely that different populations would have a different make-up of these genes, so it may all come out in the wash," he said. In other words, East Asians and Africans probably have other brain enhancing alleles, not yet discovered, that have spread to high frequency in their populations.

He said he expected more such allele differences between populations would come to light, as have differences in patterns of genetic disease. "I do think this kind of study is a harbinger for what might become a rather controversial issue in human population research," he said. But his data and other such findings "do not necessarily lead to prejudice for or against any particular population."

A greater degree of concern was expressed by Francis Collins, director of the National Human Genome Research Institute. He said that even if the alleles were indeed under selection, it was still far from clear why they had risen to high frequency, and that "one should resist strongly the conclusion that it has to do with brain size, because the selection could be operating on any other not-yet-defined feature." He added that he was "worried about the way in which these papers will be interpreted."

Dr. Sarah Tishkoff, a geneticist at the University of Maryland and a coauthor of both studies, said the statistical signature of selection on the two genes was "one of the strongest that I've seen." But she said, like Dr. Collins, that "we don't know what these alleles are doing" and that specific tests were required to show they in fact influenced brain development or were selected for that reason.

Dr. Lahn acknowledges this point, writing in his article that "it remains formally possible that an unrecognized function of microcephalin outside of the brain is actually the substrate of selection."

Another geneticist, David Goldstein of Duke University, said the new results were interesting but that "it is a real stretch to argue for example that microcephalin is under selection and that that selection must be related to brain size or cognitive function."

The gene could have risen to prominence through a random process known as genetic drift, Dr. Goldstein said.

Richard Klein, an archaeologist, who has proposed that modern human behavior first appeared in Africa because of some genetic change that promoted innovativeness, said the time of emergence of the microcephalin allele "sounds like it could support my idea."

But if the allele really did support enhanced cognitive function, "it's hard to understand why it didn't get fixed at 100 percent nearly everywhere," he said. Dr. Klein suggested that perhaps the allele had spread for a different reason, that as people colonizing East Asia and Europe pushed northward they had to adapt to much colder climates.

Commenting on these critics' suggestions that the alleles could have spread for some reason other than their effects on the brain, Dr. Lahn said he thought such objections were in part scientifically based and in part due to reluctance to acknowledge that selection could occur in a trait as controversial as brain function.

The microcephalin and ASPM genes are known to be involved in determining brain size and so far have no other known function, he said. They are known to have been under selective pressure during primate evolution as brain size increased, and the chances seem "pretty good" that the new alleles are a continuation of that process, Dr. Lahn said.

Dr. Lahn said he had tested the possibility that the alleles had spread through drift, as suggested by Dr. Goldstein, and found it was very unlikely.

Its probably a first step to prove in the genes what many scientists and my person said, that progressive Eurasians (Europids and Mongolids) have undergone a strong selection, evolved on in the classical Homo direction - evolution of the brain and behaviour, especially during the LGM, whereas those living in areas comparable to the original Homo environment in Africa had a much slower development, partly, especially in isolated populations like in Australia almost none.

Northern Paladin
Friday, September 9th, 2005, 05:11 PM
Which factors do you think have made Eurasians more intellectually advanced?

Kalevi
Friday, September 9th, 2005, 08:26 PM
That the genetic changes have anything to do with brain size or intelligence "is totally unproven and potentially dangerous ..."

Yes it is - for the scientist and his career.


Lahn's testing did find geographic differences in populations harboring the gene variants today. They were less common in sub-Saharan African populations, for example.

Oh, that's surprising. :coffee: :negro000:

Arcturus
Saturday, September 10th, 2005, 12:30 AM
"May still be evolving"... Man's arrogance never ceases to amaze me. What would make anyone think this is the pinnacle of human development? Certainly, the way things are going it probably will be as we will destroy ourselves, but this sort of thinking disgusts me just as much as religious babble concerning Man being some god's greatest (and final) creation.

Evolution wont stop just because we're smart enough to know it exists. What we would eventually evolve into I dont know, but by following the development in the past some guidelines would be; larger (or more complex) brain, thinner skeletal structure etc.

Agrippa
Saturday, September 10th, 2005, 02:21 AM
Which factors do you think have made Eurasians more intellectually advanced?

The harsh and instable climate, the need for planning especially through the winter. Its well known that in general, both for Europids and progressive Mongolids of the Northern regions life was different, they had to plan, they lived in bigger groups, hunted in complex organised units, had an improved social system, different kind of sexual selection because both the male and the female had to rely much more on each other and a male could take every female, but he thought twice whether it was worth the investment, because it could be his only chance, again different from certain tropical regions.

Furthermore the Mongolids themselves had the advantage of producing a skin type which was versatile, if you compare the variation of Europid skin in the same climatic regions with that of Mongolids, you will be impressed by the more stable Mongolid condition. I dont want to explain the whole Mongolid skin structure now, but I can just say it seems to be, like the other features, an adaptation to the UV-rich open regions of the Cold and brought up a type which could survive both in rather UV-poor and rich areas easier without extreme variation (like Europids).

Other features of the Mongolid type are the social adaptation, lower level of individual aggression and less extreme masculine tendencies. (Negrids are in fact the opposite). They are a very frugal, partly simple type which can stand suffering better, especially in social unity if its about the typical Mongolid variant. Of course culture evolved in the same direction because of the same reasons and needs.
I think the basic tendencies came up during the LGM in which the former bigger groups melted down in the worst time to small groups which had to fully cooperate, stand suffering and acting planned to survive and reproduce again. After this type evolved, and because parts of East Asia were still quite primitive, this specialised groups almost explode and pushed others away, next wave followed and pushed the last, which ...
Like the big ancient migration of the Germanic people, one pushed the other, just with the difference that this people had a bigger impact genetically, because the density was low in the LGM. After that they had already the North of Asia and Northern China, but still not the whole region. That came with rice expansion, the Neolithic spread of this type...and this time the same thing happened as before, just with much more people and with other cultural features.
We can differ two types of basic Mongolids, the Arctic (Tungid and related) and the Sinid (and related) with the later having an influence of the South from early on, but during the selection period the primitive features were mostly bred away and finally produced an even more progressive type.

Aesthetic selection is not inevitably correlated with psychological improvements, especially not with intelligence, but more with hormonal status and personality.
The intelligence selection was independently stronger in the temperate and cold climate and bigger social units (in the tropics were even at the time of H-G the groups smaller) for which less aggressive intragroup behaviour but the ability to use disciplined aggression in the intergroup selection was crucial.

So, there could be primitive looking groups on this planet which are more intelligent, but as things are, that is not the case because the evolution which lead to new physical adaption away from the tropical types was crucial for the higher intelligence and social more adapted behaviour too.

Furthermore a good physical shape and condition, both efficiency and attractiveness are important features on their own. You say that are only attractive features, but thats not true, they go deeper and are on-line with the past evolvement of humanity. I made other threads and posts about that topic, especially about skull hole (foramen magnum) position-orthognathy-spine evolution...
Furthermore you can have mixed status, f.e. certain progressive features combined with primitive (most obvious full lips with prognathy).

The correlation between general attractiveness and average higher intelligence is proven and whats proven too is that chances are higher that partner selection leads to the combination of attractiveness and intelligence.

F.e. under extreme selection in a new environment, what kind of women will the more intelligent and stronger male take? The ugly, primitive and less healthy looking? Especially if he must do more for her, because in the tropics the women can go on and work for their own nutrition and probably the children too, the male must not be always there or successful. Especially during the last LGM the males had oftentimes the full responsibility to care for the women and children nutrition - they must be successful and intelligent hunters and attack others for, or defend their own winter ressources.
Under the tropical conditions males didnt selected so much and females neither, they both looked just to reproduce and that the body is strong and healthy, the character of the person, the sympathy in the face was probably less important because investment and risk was lower too.
A male during the LGM might have been investing all he had of energy in just 4 children of one or two women, if they were treacherous or unhealthy, had no good genes themselves his life was lost. Especially if he went on his long hunting work he had to rely on the ability and fidelity of the woman.
Most small tropical hunters went with their women or didnt used such a great radius as the Northern H-G groups with their bigger social systems in which single male aggression without discipline couldnt be tolerated.
To think ahead, especially if its about planning a family and surviving the winter was crucial.

Dr. Solar Wolff
Saturday, September 10th, 2005, 05:19 AM
From the article, I am having trouble determining if this is a new position on the chromosome (new gene) or two new varients of a gene (alleles). Also, on the link article it mentions two dates determined via genetic clock technology (?), 37,000 and 5,800 for the two genes in question.

The big reason why all these "scientists" are wringing their hands and hedging their statements is also found in the link article. There are differences between races, especially poor in the new genes (alleles) are the sub-Saharan races but secondly, in the case of the 5,800 mutation, the East Asiatics share in this much less frequently. What is a scientist to do? In this instance he cannot tell the truth even though the truth can be stated in terms of mathematics.

Who are these guys trying to kid when the discuss the origins of sapiens or the origins of creative thinking circa 200,000 years ago--in Africa???? This is why Anthropologists are such whores--throw in the cowards in Genetics in this instance.

37,000 years---entrance of sapiens into Europe
5,800 years---- spread of Indo-European languages and people.

lei.talk
Saturday, September 10th, 2005, 05:21 AM
the idyllic life-style
on the exposed continental shelf
during the last ice-age,

posed few challenges
to the inhabitants
and, consequently,
few adaptations took place.

contrastingly, the inhabitants
of the interior
of the eur-asian continent
were harshly challenged
by the environment
and some evolved
into the most advanced human form.

certainly, nordic man
(before christianisation and urbanisation (http://www.forums.skadi.net/showpost.php?p=116515&postcount=3))
was the most genetically gifted
and had the maximal expression of genetic material (http://www.forums.skadi.net/showpost.php?p=116633&postcount=5)
yet seen in humans.

where else is to be seen
such a grand combination
brains and brawn?

erlingr's insistence on
nordic man/nordic culture/nordic land
is purposeful. (http://www.forums.skadi.net/showthread.php?t=10587)

if it is lacking,
man will continue to evolve
in to what ever varietal niches
are available.

self-conscious man should direct his life
and, at a minimum, that of his descendents.

challenge your self:

"let me strive every moment of my life
to make my self better and better,
to the best of my ability".
Otherwise it is all pointless mental masturbation.

Agrippa
Saturday, September 10th, 2005, 01:05 PM
As for the 2nd variant I think its definitely correlated with Neolithisation and there Indoeuropeanisation too. Many people argued in the past that no new mutations of significance came up in the last 10.000 years, whats absolute nonsense and many people recognised this. Evolution doesnt stop, both to higher and lower forms (degeneration) it can go on and the post-Neolithic lifestyle made up totally new selective regimes with a positive peak in the late Neolithics and Bronze Age.

Dr. Solar Wolff
Sunday, September 11th, 2005, 05:53 AM
As for the 2nd variant I think its definitely correlated with Neolithisation and there Indoeuropeanisation too. Many people argued in the past that no new mutations of significance came up in the last 10.000 years, whats absolute nonsense and many people recognised this. Evolution doesnt stop, both to higher and lower forms (degeneration) it can go on and the post-Neolithic lifestyle made up totally new selective regimes with a positive peak in the late Neolithics and Bronze Age.


The mutation allowing an adult to continue to digest lactose (continued lactase production into adulthood) is another very recent mutation and one which allowed the spread of a new method for humans to exploit the environment.

Agrippa
Tuesday, September 13th, 2005, 06:01 PM
Dienekes added some more information and theories on his own in his blog:
http://dienekes.blogspot.com/2005/09/stop-presses-huge-papers-on-brain.html
Its interesting to see how low the percentages in Subsaharan Africans (Negrids, Bambutids, Khoisanids) is. Some Pygmies, which are my prime example for a group which was pushed away poor regions, had to reduced their type in this negative environment and further infantilised AND show very primitive-plesiomorphic traits have frequencies of ASPM haplogroup D of 0 percent.
The only surprise: If the results are representative, Melanesids, mainly the Neomelanesid Papuans have quite high percentages of both allels.

Triglav
Monday, September 19th, 2005, 01:20 AM
Please find enclosed both studies.

Triglav
Monday, September 19th, 2005, 01:22 AM
Human brains enjoy ongoing evolution

* 15:06 09 September 2005
* NewScientist.com news service
* Mason Inman



The human brain may still be evolving, new research suggests. New variants of two genes that control brain development have swept through much of the human population during the last several thousand years, biologists have found.

The evolution of a large, complex brain has been the defining feature of the human lineage – although human brain size has not changed over the past 200,000 years. But it is not apparent whether the new genetic adaptations discovered in human brains have any effect on brain size, or intelligence.

What is more, not everyone possesses the new gene variants, potentially inflaming an already controversial debate about whether brains of different groups of people function differently.

"Whatever advantage these genes give, some groups have it and some don't. This has to be the worst nightmare for people who believe strongly there are no differences in brain function between groups," says anthropologist John Hawks of the University of Wisconsin in Madison, US.
Brain size

There are two new genetic studies that suggest the brain may still be evolving. Geneticist Bruce Lahn of the University of Chicago in Illinois, US, and colleagues analysed the sequences of two genes active in the brain – Microcephalin and ASPM. Both regulate brain size - people carrying a non-functioning mutant copy of these genes suffer microcephaly, where they have a normally structured brain that is much smaller than usual.

First, the researchers sequenced the Microcephalin gene found in 89 ethically diverse people. The team found dozens of variants (or alleles) of the gene, but one particular set stood out. These alleles all carry a specific mutation that changes the protein the gene codes for.

This distinctive mutation is now in the brains of about 70% of humans, and half of this group carry completely identical versions of the gene. The data suggests the mutation arose recently and spread quickly through the human species due to a selection pressure, rather than accumulating random changes through neutral genetic drift.

Analysing variation in the gene suggests the new Microcephalin variant arose between 60,000 and 14,000 years ago, with 37,000 years ago being the team's best estimate. The new mutation is also much more common among people from Europe, the Middle East, and the Americas than those from sub-Saharan Africa.
“Compelling evidence”

The team also sequenced the ASPM gene from the same original sample and again, among dozens of variants, found a defining mutation that alters the protein the gene codes for. Estimates are that the new variant of ASPM first appeared in humans somewhere between 14,000 and 500 years ago, with the best guess that it first arose 5800 years ago. It is already present in about a quarter of people alive today, and is more common in Europe and the Middle East than the rest of the world.

"The evidence for selection is compelling," says population geneticist Rasmus Nielsen of the University of Copenhagen in Denmark. Yet it remains unclear yet how these genes work in healthy people. Many researchers doubt there is any mechanism by which nature could be selecting for greater intelligence today, because they believe culture has effectively blocked the action that natural selection might have on our brains.

Lahn and his colleagues are now testing whether the new gene variants provide any cognitive advantage. Natural selection could have favoured bigger brains, faster thinking, different personalities, or lower susceptibility to neurological diseases, Lahn says. Or the effects might be counter-intuitive. "It could be advantageous to be dumber," Lahn says. "I highly doubt it, but it's possible."

Journal reference: Science (vol 309, p 1717 and p 1720)

http://www.newscientist.com/article.ns?id=dn7974

Triglav
Monday, September 19th, 2005, 02:42 AM
Maps:

http://www.forums.skadi.net/attachment.php?attachmentid=6000&d=1127094116

http://www.forums.skadi.net/attachment.php?attachmentid=6001&stc=1&d=1127094323

alphaknave
Wednesday, September 21st, 2005, 04:43 AM
Very interesting.

It is a little bit confusing to me however. Concerning physical attractiveness and intelligence, are you (Agrippa) saying that the Neolithic or progressive (pardon me if they are different) types are more evolved? Would a Paleolithic type be therefore less intelligent and "primitive"? Saying that, wouldn't that make Asians (Arctic) more intelligent since they are typically more progressive than Europeans who have a mixture of Paleolithic and Neolithic attributes? Therefore, do we all desire Neolithic and progressive properties? Thanks in advance for clearing this up for me.



I just found this explination by Agrippa made a while back:

Europids are just the most balanced AND progressive human types. The combination of attractiveness, balanced-progressive physical and mental features makes them the first choice though certain progressive types especially of the Mongolid race are not too far away and mixed types can sometimes reach a very high level as well.

But on average the Europids are the best variant considering as many areas as possible.

Non-Europid types on a similar level are mainly/f.e. Sinids, the Japanese-Korean-Tibetan types, Northern (more progressive) Palaemongolids (Shanid) and Sylvids (woodland Indians).
They live all more or less in a rather temperate climate which seems to be the optimal environment for human development without furthering extreme specialization on the one hand, but making humans flexible and adaptive on the other.

Interestingly those types you could consider being progressive physically are usually more intelligent and socioculturally successful on average as well...
Thats true in almost every region and ethnic group of the world, at least as long as an advanced system, culture exists...

That pretty much answers my question, but elaboration is still welcome. :)

Dr. Solar Wolff
Wednesday, September 21st, 2005, 06:06 AM
The harsh and instable climate, the need for planning especially through the winter. Its well known that in general, both for Europids and progressive Mongolids of the Northern regions life was different, they had to plan, they lived in bigger groups, hunted in complex organised units, had an improved social system, different kind of sexual selection because both the male and the female had to rely much more on each other and a male could take every female, but he thought twice whether it was worth the investment, because it could be his only chance, again different from certain tropical regions.
Furthermore the Mongolids themselves had the advantage of producing a skin type which was versatile, if you compare the variation of Europid skin in the same climatic regions with that of Mongolids, you will be impressed by the more stable Mongolid condition. I dont want to explain the whole Mongolid skin structure now, but I can just say it seems to be, like the other features, an adaptation to the UV-rich open regions of the Cold and brought up a type which could survive both in rather UV-poor and rich areas easier without extreme variation (like Europids).
Other features of the Mongolid type are the social adaptation, lower level of individual aggression and less extreme masculine tendencies. (Negrids are in fact the opposite). They are a very frugal, partly simple type which can stand suffering better, especially in social unity if its about the typical Mongolid variant. Of course culture evolved in the same direction because of the same reasons and needs.
I think the basic tendencies came up during the LGM in which the former bigger groups melted down in the worst time to small groups which had to fully cooperate, stand suffering and acting planned to survive and reproduce again. After this type evolved, and because parts of East Asia were still quite primitive, this specialised groups almost explode and pushed others away, next wave followed and pushed the last, which ...
Like the big ancient migration of the Germanic people, one pushed the other, just with the difference that this people had a bigger impact genetically, because the density was low in the LGM. After that they had already the North of Asia and Northern China, but still not the whole region. That came with rice expansion, the Neolithic spread of this type...and this time the same thing happened as before, just with much more people and with other cultural features.
We can differ two types of basic Mongolids, the Arctic (Tungid and related) and the Sinid (and related) with the later having an influence of the South from early on, but during the selection period the primitive features were mostly bred away and finally produced an even more progressive type.
Aesthetic selection is not inevitably correlated with psychological improvements, especially not with intelligence, but more with hormonal status and personality.
The intelligence selection was independently stronger in the temperate and cold climate and bigger social units (in the tropics were even at the time of H-G the groups smaller) for which less aggressive intragroup behaviour but the ability to use disciplined aggression in the intergroup selection was crucial.
So, there could be primitive looking groups on this planet which are more intelligent, but as things are, that is not the case because the evolution which lead to new physical adaption away from the tropical types was crucial for the higher intelligence and social more adapted behaviour too.
Furthermore a good physical shape and condition, both efficiency and attractiveness are important features on their own. You say that are only attractive features, but thats not true, they go deeper and are on-line with the past evolvement of humanity. I made other threads and posts about that topic, especially about skull hole (foramen magnum) position-orthognathy-spine evolution...
Furthermore you can have mixed status, f.e. certain progressive features combined with primitive (most obvious full lips with prognathy).
The correlation between general attractiveness and average higher intelligence is proven and whats proven too is that chances are higher that partner selection leads to the combination of attractiveness and intelligence.
F.e. under extreme selection in a new environment, what kind of women will the more intelligent and stronger male take? The ugly, primitive and less healthy looking? Especially if he must do more for her, because in the tropics the women can go on and work for their own nutrition and probably the children too, the male must not be always there or successful. Especially during the last LGM the males had oftentimes the full responsibility to care for the women and children nutrition - they must be successful and intelligent hunters and attack others for, or defend their own winter ressources.
Under the tropical conditions males didnt selected so much and females neither, they both looked just to reproduce and that the body is strong and healthy, the character of the person, the sympathy in the face was probably less important because investment and risk was lower too.
A male during the LGM might have been investing all he had of energy in just 4 children of one or two women, if they were treacherous or unhealthy, had no good genes themselves his life was lost. Especially if he went on his long hunting work he had to rely on the ability and fidelity of the woman.
Most small tropical hunters went with their women or didnt used such a great radius as the Northern H-G groups with their bigger social systems in which single male aggression without discipline couldnt be tolerated.
To think ahead, especially if its about planning a family and surviving the winter was crucial.

Early Mongoloids such as American Indians do show regional variation in most things. The Later Mongoloids, the ones with the eyefold, show much less variation as Agrippa states. Yet, the Early and Later Mongoloids seperated at about 20-25,000 B.P., before the last glaciation. By this time humans were adapting mainly through culture not natural selection. Yet, the Later Mongoloids show very pecular and special physical adaptations, made in isolation in Asia, while surrounded by ice. Their adaptation was mostly physical since there were no big breakthroughs at this time in culture, the ivory harpoon being the only possible exception. So, if the Later Mongoloids are so bright, why were they letting natural selection rather than culture combat the environment for them?

Something else is going on here which genetics and anthropology refuse to investigate let alone confront.

anonymaus
Saturday, October 1st, 2005, 10:14 AM
It would be unprecedented arrogance and baffling ignorance to assume that the human brain is anywhere near "completely" developed. The very idea is antithetical to evolution itself. If the species survives long enough to develop past this embryonic stage - which it very well may given that human beings currently act much like cockroaches, though they are even less symbiotic with nature - some one, some day, may be able to say "Okay, now what?"

Until then, the shark is the only creature I'm aware of which doesn't need to evolve any further--yet.

All Nords are living testament to the never-ending progressive nature of existence; we can measure this scientifically and judge it culturally. Life itself is a struggle: our ancestors worked hard - fought hard - to ensure their legacies, and our improvement, were secure. What is new becomes old, old becomes ancient, ancient becomes dust; dust blows away and carries with it the newly forgotten. All generations of our people must strive - and thrive - to continue this legacy. Personal sacrifice, group gain.

Our very existence is proof that surviving inimical conditions engenders inimitable amelioration.

We are now faced with a great challenge. in our societies, in our lives - not to exist as we have, but to progress and strive towards the next level of our existence. I worry if enough of our people will be awake, and aware, of the dire situation of their kin as the next several decades unfold and their condition - our condition - degenerates even further.

We have precious little time on this planet to do what we must, and most people squander it by doing what they wish--without considering the ramifications of their actions. Survival/Extinction is not a social issue up for academic debate and discussion; it is a - self-evident - binary problem: You do one or the other is done to you. Progression of our lineage and our cultural inheritance is up for academic debate - it is a social issue. We must rise above this simple view of preservation as mere survival. We must lift the veil, we must convince our people that they are worthy of existing--and improving.

We must progress.

Nagelfar
Friday, January 19th, 2007, 08:32 PM
The gene ASPM (abnormal spindle-like microcephaly associated) is a specific regulator of brain size, and its evolution in the lineage leading to Homo sapiens was driven by strong positive selection. Here, we show that one genetic variant of ASPM in humans arose merely about 5800 years ago and has since swept to high frequency under strong positive selection. These findings, especially the remarkably young age of the positively selected variant, suggest that the human brain is still undergoing rapid adaptive evolution.


he most recent ASPM gene variation arose about 5,800 years ago, roughly correlating with the development of written language, spread of agriculture and development of cities. Currently, two variations of this gene exist: the older variation (pre-5,800 years ago) and the newer variation (post-5,800 years ago). About 10% of humans have only the "new" ASPM gene, while about 50% have only the "old" version. The other 40% of humans have both genes

I wonder what populations 'have only the new gene' and which 'have the new & old gene'. I'm assuming sub-saharan African populations have a high frequency of just the old gene, if only because of their archaic haplogroup structural mutations. Though sub-saharan Africans can't make up such a great figure as 50% of the human population.