Human brain still evolving

[Skye]

A recent paper indicates that the brain has undergone genetic changes during the history of modern humans. The researchers worked on two genes that cause microcephalopathy when inactivated by mutation, and tracked polymorphisms of each gene in study groups. They found that, for each gene, a particular goup of polymorphisms had been positively selected for. The actual function of the genes isn't known with certainty, and the authors are keen to avoid any ubermensch talk.

 

Link

[the tree]

Well duh, why would anything stop evolving unless it were perfectly adapted to an eviroment that stayed the same for many generations (stupifyingly unlikely)?

[Martin]

This is extremely interesting, potentially important work. It seems very solid. It will provoke a lot of controversy (people will be apprehensive about polit. incorrect interp.)

 

Skye, I posted a note about this work yesterday morning (Friday) in the NEWS section of SFN. It hasnt shown up there because there is a kind of queue of news items, I guess.

 

I gave a link to a New York Times science section discussion of the Lahn work (microcephalin and ASPM genes).

 

Please, people who bring thoughtful responses to this thread, when the NEWS item gets posted, please transfer some of your posts over! That way good comments wont all happen here and nothing cooking in the news thread. Thanks

 

A recent paper indicates that the brain has undergone genetic changes during the history of modern humans. The researchers worked on two genes that cause microcephalopathy when inactivated by mutation' date=' and tracked polymorphisms of each gene in study groups. They found that, for each gene, a particular goup of polymorphisms had been positively selected for. The actual function of the genes isn't known with certainty, and the authors are keen to avoid any ubermensch talk.

 

Link

[Martin]

Skye, the NYT article is here:

http://www.nytimes.com/2005/09/08/science/08cnd-brain.html?ei=5094&en=7f83ee9b96d40611&hp=&ex=1126238400&adxnnl=0&partner=homepage&adxnnlx=1126212523-Sy51vhmKhac0/YQeUBpASA&pagewanted=all

 

your HHMI press release link was

http://www.hhmi.org/news/lahn4.html

and there was this further link

http://www.hhmi.org/research/investigators/lahn.html

 

 

Here is some dynamite from the New York Times:

 

"...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..."

 

So if you ignore the error bars, the first gene variant (allele) emerged around 37,000 ago-----that is 35,000 BC

 

and the second allele emerged around 5,800 ago---that is 3,800 BC.

 

This roughly corresponds to spread of agriculture and building the first cities and invention of writing.

 

OK OK now we do not jump to conclusions. the first thing is there is a lot of very interesting science

 

why did these genes spread? do they have positive side effects unrelated to brain function which might give them a selective advantage?

where they are lacking or rare in a population are there OTHER genes which have the same function?

do these genes actually have anything demonstrable to do with brain function?

if so, could THAT have given them a selective advantage so that they spread thru the populations in certain regions.

geneticists dont just talk on a purely verbal level (where everything may appear obvious) but instead try to be very concrete and put their finger on exactly this measurable thing and demonstrate exactly that mechanism. the scientific questions of proving exactly what and how it happens take priority which is so cool!

 

so Lahn work at Howard Hughes is taking a bunch of speculative notions and bringing it down to specifics that they can research, I think it will be very influential research

[rakuenso]

I don't really see the importance of this though as long as we don't undergo speciation.

[Martin]

I don't really see the importance of this though as long as we don't undergo speciation.

 

speciation could be arranged

 

a tiny bit of genetic engineering could split off a small immiscible gene pool from the main one

 

I dont understand your idea of "importance"

 

knowledge and understanding has intrinsic value to me, I would like to understand human history better, and culture, and genetic history is part of that. It is fascinating. why do certain sub-populations have a high concentration of this or that professional/artistic excellence and why do so many tackles come from Tonga? if there is a genetic component, how was it selected for historically?

 

one does not have to imagine splitting the human gene pool into several species (which technically could be done if it were desirable) in order to make these questions about our common history as mankind interesting.

 

anyway I think this Lahn work is going to trigger a big controversy and lots of followup research by lots of people

[the tree]

Martin, after your burst of long sentances does my statement of "well duh..." still stand? Surely it would be really wierd if the human brain wasn't evolving.

[Martin]

Martin, after your burst of long sentances does my statement of "well duh..." still stand? Surely it would be really wierd if the human brain wasn't[/i'] evolving.

 

Dear tree,

 

what headline would you give to this NYT article?

http://www.nytimes.com/2005/09/08/science/08cnd-brain.html?ei=5094&en=7f83ee9b96d40611&hp=&ex=1126238400&adxnnl=0&partner=homepage&adxnnlx=1126212523-Sy51vhmKhac0/YQeUBpASA&pagewanted=all

 

Pretend you are a journalist, say a science editor, read the article, and make up a headline for it.

 

Please notice that the article DOES NOT SIMPLY SAY "BRAIN IS EVOLVING".

If that general statement were all, then it wouldnt be very interesting, as you may have meant to point out.

the article says something else. What does it say to you, tree?

[the tree]

"Latest evolution in the brain found" but I see your point.

 

What does it say to you, tree

It says to me that they've observed some evolution, like they do quite often but the new thing is that it's in the brain.

 

If you look at the statements such as "we don't know what these alleles are doing" it implies that they've just confirmed that evolution is happening wich was close to certain in the first place and being no expert I can't see what benifit this confirmation would bring.

[Martin]

 

...It says to me that they've observed some evolution' date=' like they do quite often but the new thing is that it's in the brain.

...[/quote']

 

Skye or Mokele or one of the others might come in and say this more clearly, but I will stab at it. To me the article says something that I don't see how to compress into a headline because what is significant is the RATE and the fact that they have identified two particular genes.

 

Lots of things about us are stable, they may evolve but very very slowly so that you wouldnt notice any change in maybe 100,000 years. Some of our other organs. skeletal and muscular things too, probably have been moderately stable for like 20,000.

 

But here are these two genes that only go back to3800BC or 37,000BC which have spread throughout a large chunk of the population or area-wise on the planet. It is a comparatively RAPID rate of evolving. That impresses me. (maybe i am wrong but that is how it looks to me)

 

and I am impressed by the exactitude and concreteness. they just dont know in some vague way that our organs do gradually evolve . they can point to these two genes and put a date on when they appeared.

 

so my headline would be something like:

 

"Rapid brain evolution observed exactly!"

 

You can see that would never go over as a headline, but what can I say?

[Skye]

Skye, I posted a note about this work yesterday morning (Friday) in the NEWS section of SFN. It hasnt shown up there because there is a kind of queue of news items, I guess.

Ok, maybe this thread can be merged with it when it gets added to the news.

[the tree]

Thankyou very much, not being a biologist I wouldn't have know that the rate they observed was so comparatively fast.

[Martin]

Ok, maybe this thread can be merged with it when it gets added to the news.

 

Sounds like a plan. If whoever decides.

 

How do biologists gauge the speed that some organ or process in the body is evolving?

 

The Tree may be wondering about this too.

 

I suppose the "time" measure is GENERATIONS. One reason microbes and insects can evolve chemical resistance or other characteristics very fast on a scale of years or decades is they go thru generations fast.

 

Maybe there is a rough notion of what to expect with animals our size and lifespan.

 

I get the impression that some species are remarkably stable and can go through a million generations without anyone being able to see any change.

And with humans probably at least SOME ORGANS are not seen to be evolving noticeably, as far as we can tell. Human skeletons from 1000 generations ago are probably hard to tell apart from today's

 

Anyway the NYT article specifically said RAPID, as I remember. It did not come thru in their headline but they made it plain in the article that what had been discovered was unusual or newsworthy partly because it was recent, indicating a rapid evolution

 

(I guess compared with more slowly evolving organs like my toes, or my liver, if they are slow-evolvers )

[Martin]

Thankyou very much, not being a biologist I wouldn't have know that the rate they observed was so comparatively fast.

 

You are most welcome! I am not a biologist either and often have trouble seeing what they are driving at. Since you read the New York Times article, you may recall that the first sentence was:

 

"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."

 

Often in journalism the headline is just too short to get across the idea, so they expand on the headline in the first sentence, and say it more carefully or clearly.

 

We have the same limitation at Forums----the thread name has to be short to be read in the menu, so it may only give an idea of the general topic the thing is about, but not actually carry the full message.

 

And I STILL don't know really what "rapid" means here!

 

Apparently some gene appeared (that may have a significant effect and confer some survival or reproductive advantage) as recently as 6000 years ago and spread like wildfire thru the human population. So you start with a fairly large and widely dispersed population of huntgather humans and you set off this gene and within 4000 years it spreads to most of the population at least outside SubSahara (where it has made some inroads as well but not so much). Is 6000 years subjectively a short time or a long time? these biologists seem to think it is short, for a gene to spread. So if I trust them then I have to train our time-perspective and adjust my expectations about evolution accordingly. It still remains rather subjective and approximate but that is how a lot of things always are.

[Martin]

Here's a pithy quote from the HHMI press release:

 

"Their statistical analysis indicated that the Microcephalin haplogroup D appeared about 37,000 years ago, and the ASPM haplogroup D appeared about 5,800 years ago - both well after the emergence of modern humans about 200,000 years ago. “In the case of Microcephalin, the origin of the new variant coincides with the emergence of culturally modern humans,” said Lahn. “And the ASPM new variant originated at a time that coincides with the spread of agriculture, settled cities, and the first record of written language. So, a major question is whether the coincidence between the genetic evolution that we see and the cultural evolution of humans was causative, or did they synergize with each other?”

 

so he points to two historical events

 

A. emergence of culturally modern humans

(what does that mean? fire, cave drawings, clothes, burial of the dead? use of spoken language? certain kinds of tools or ornaments? I don't know what he means or how anybody would know) and

 

B. spread of agriculture, settled cities, and the first record of written language

 

he says that A happened roughly around 37,000 years ago and the B happened around 5000 years ago.

 

Supposedly that is all already figured out by paleo, anthro, archeology people.

 

Now he gives his result. He says EACH OF THESE TWO IMPORTANT EVENTS IN HISTORY WAS ACCOMPANIED BY THE MUTATION AND SPREAD OF A CERTAIN GENE which the team has identified.

 

whether it helped cause it, or was caused by it, or had anything to do with it, he does not say----so far no proof of any connection, only various possible conjectures. sorting out the connections, if any, between historical development and gene-spread can be a good topic for later research.

 

I think it is interesting because I can easily imagine that both these events, A and B, could have occurred PURELY BY CULTURAL EVOLUTION with no accompanying genetic evolution at all. So I guess the deeper news here is that these cultural developments (cavedrawing, language, cities, writing whatever) may have been accompanied by genetic change.

[Skye]

Dating method for the ASPM gene

 

time since most recent common ancestor = 2(T/D)*L

 

T=estimated number of mutations per base in the sequence being studied since a theoretical most recent common ancestor

D=estimated number of mutations per base in the gene compared to a chimp homolog

L=estimated time since chimps and humans diverged

 

=2(4.2x10^-6/0.00865)*6 million years

=5826 years.

[Martin]

Dating method for the ASPM gene

 

time since most recent common ancestor = 2(T/D)*L

 

T=estimated number of mutations per base in the sequence being studied since a theoretical most recent common ancestor

D=estimated number of mutations per base in the gene compared to a chimp homolog

L=estimated time since chimps and humans diverged

 

=2(4.2x10^-6/0.00865)*6 million years

=5826 years.

 

I am totally new to this, please explain or see if I am getting this right: D is like a clock, you spread out all those D differences over a 6 million year period where the two species were diverging and you see that there is a divergence rate of

 

D/2 per 6 million years for each, adding up to D per 6 million total.

 

it is D/2 because both species are moving away from each other so the distance grows at twice the rate each is moving (this has a simplifying symmetry assumption which seems reasonable)

 

so the human gene is moving at D per 12 million years, per base pair.

 

Now you look at just this ittybitty sequence of a few basepairs and you see how much IT has changed per base pair, that is T

 

and so you consult the clock and you say HOW LONG DOES IT TAKE HIM TO TRAVEL A DISTANCE T IF HE MOVES AT SPEED D/(12 million years)?

 

Ah hah. that gives the formula what you say. and it works out to 5800 years as it is supposed to, good.

[LucidDreamer]

Finding two genes associated with microcephaly in humans, comparing them to other primates, and then identifying polymorphisms among current populations of Homo sapiens is very interesting and important, meaningful science. Trying to associate the emergence and frequency of the polymorphisms with the creation of culture and civilization is speculative. Suggesting that the popular forms of these genes somehow endow people with a substantially superior capacity to create culture and civilization is unsubstantiated and silly. Not that anyone on this forum has really suggested this; it just seems to me that somebody might take that interpretation from the article.

 

I haven't really delved too deeply into this study, but I'm not really convinced that the popular forms of these genes even give an advantage. Some alleles, that are mostly neutral in their endowment, are spread and propagated without the means of specific natural selection. The Romans weren’t necessarily genetically superior to other people, yet they spread their people's genes all over Europe and the Mediterranean. The English weren't necessarily superior when they were spreading their genes all over the globe during their imperialism. Outside factors can influence the frequency of polymorphic forms of genes.

[Martin]

the word you are introducing into the discussion here, Lucid, is superior. you want us to think in terms of "superiority" and "inferiority" so you repeat the word several times:

 

Finding two genes associated with microcephaly in humans' date=' comparing them to other primates, and then identifying polymorphisms among current populations of Homo sapiens is very interesting and important, meaningful science. Trying to associate the emergence and frequency of the polymorphisms with the creation of culture and civilization is speculative. Suggesting that the popular forms of these genes somehow endow people with a substantially [b']superior[/b] capacity to create culture and civilization is unsubstantiated and silly. Not that anyone on this forum has really suggested this; it just seems to me that somebody might take that interpretation from the article.

 

I haven't really delved too deeply into this study, but I'm not really convinced that the popular forms of these genes even give an advantage. Some alleles, that are mostly neutral in their endowment, are spread and propagated without the means of specific natural selection. The Romans weren’t necessarily genetically superior to other people, yet they spread their people's genes all over Europe and the Mediterranean. The English weren't necessarily superior when they were spreading their genes all over the globe during their imperialism. Outside factors can influence the frequency of polymorphic forms of genes.

 

I would rather avoid such strongly colored terms, that could have such a value slant, if possible. that is just my personal preference, though, and you can talk and argue about anything you want----like whether there was any genetic component contributing to the Mongol success in conquering much of Asia around 1200 AD which had an enormous genetic impact (it has been measured, the number of direct descendents of Genghis Khan is staggering)

 

things like this happen in evolution. some bees of a given type get loose and after a while their genes are spread all thru the native population because those bees happen to be good at doing whatever a bee has to do to get its genes widely spread-----just let's call it something like "reproductive advantage" rather than superiority. OK?

 

and realize that reproductive advantage can derive from purely cultural circumstances, with no genetic component at all! as well as from some contributing genetic factors.

[Martin]

more links about this:

this is from a blog called GENE EXPRESSION used by genetics and bio people:

http://www.gnxp.com/blog/2005/09/this-is-bruce-lahns-brain-on-aspm-and.php

(I found some of the comments, 82 so far, interesting---had an inside profession flavor)

 

 

here are two articles in the journal Science

http://www.sciencemag.org/content/current/#researcharticles

(scroll about 1/3 of the way down the page)

 

many articles on Google News

http://news.google.com/news?hl=en&ned=us&ie=UTF-8&ncl=http://www.washingtonpost.com/wp-dyn/content/article/2005/09/08/AR2005090801254.html

 

GENETICS AND PUBLIC HEALTH BLOG has a bit on it

http://www.aboutweblogs.com/genetics/item/1731

(with links to several other articles about genetic effects)

[LucidDreamer]

the word you are introducing into the discussion here' date=' Lucid, is [b']superior[/b]. you want us to think in terms of "superiority" and "inferiority" so you repeat the word several times:

I may have introduced the word, but the term is implied in the article Skye linked to. Evolution is about adaptation to pressure, which results in improvements in an organisms ability to deal with his environment. When we speak of culture and civilization we speak of the very essence of what makes us human and separates us from the rest of the animal kingdom. An adaptation in humans that allows one population to produce more culture and a more efficient civilization is the very essence of superiority with regard to humans. We could give lip service to idea that genes and alleles that allow more culture and a better means to organize are not necessarily superior to not having the alleles, but tell that to the Neanderthals.

 

My point is this: There are three possibilities that I can think of that would result in the very loose correlation between the polymorphic forms of these genes, and the advent of culture and civilization:

 

1) The popular and "superior" polymorphic forms of these genes preceded the proliferation of culture and civilization and provided an important genetic endowment to establish a more advanced society.

 

2) The popular and "superior" polymorphic forms of these genes were introduced into the population after the proliferation of culture and civilization and are a beneficial adaptation that gives somebody better chances to survive and procreate in an advanced society.

 

3) The popular and "superior" polymorphic forms of these genes provide no real benefit over the other forms in the creation of culture and civilization or the survivalability of an individual inside an advanced society and the greater frequency of certain polymorphic forms can be attributed to other factors. Another possibility is that the popular polymorphic forms of these genes provide some other benefit not related to culture or civilization, such as a greater resistance to encephalitis.

 

The first two possibilities are basically what it seems the researcher is implying with his comments and I was only trying to offer an alternative possibility.

 

Martin, it seems strange to me that you think I am trying to purposely and unnecessarily use inflammatory language when the very essence of the article is that there are two genes related to brain size, culture, civilization, and intelligence and that there are differences between Homo sapiens and primates and even differences within Homo sapien populations. I think the word superior is a very relevant word; a man may not be superior to a chimpanzee, but we only give citizenship and attribute human rights to one. The other one is kept in zoos with nothing to occupy his time other than to throw poo at his fellow inmates.

[Martin]

I may have introduced the word, but the term is implied in the article Skye linked to...

 

sorry

 

I dont think so

 

maybe it is "implied" to you if you are very superiority conscious

objectively implied? no.

term used? no.

 

if you can show a passage where the HHMI press release that Skye linked

had some kind of value slant on the genetic alleles or put some "superiority" spin then please QUOTE THE PASSAGE

I want to see the word "superior" used explicitly or a synonym or a clear implication.

 

if you can show them being unscientific and value-loaded and quote a passage (not just your own philosophical reasoning) then if it looks objectionable to me then I will write them about it.

 

if you cannot quote the HHMI press release, then fine

I wont waste any more time with this

[Martin]

I'm asking you to put up or shut up, Lucid. You have accused the report-writer at Howard Hughes of unprofessional conduct.

 

Show the passage at fault, or retract your accusation.

[Martin]

I may have introduced the word, but the term is implied in the article Skye linked to...

 

You cast aspersions on someone who writes press releases for HHMI. It would be unworthy and unscientific of him/her to put a value judgement bias on these alleles.

 

If you can show that the article is actually at fault, fine. Convince me by showing me. I will write to the guy's boss and let them know that the press release was written with an unscientific slant. In a case like this with high visibility that would be a serious screwup and the writer should be held accountable (or the editor who cleared the release)

 

If you cannot show this, then your accusation is unfounded and morally you should retract it.

 

so lets hear how you substantiate that the term "superiority" with its value connotations is "IMPLIED" in the actual HHMI press release that Skye linked.

 

I am happy either way. if you can prove your point, fine. if you cannot prove it and wish to retract, fine. no problemo either way.

[LucidDreamer]

if you can show a passage where the HHMI press release that Skye linked

had some kind of value slant on the genetic alleles or put some "superiority" spin then please QUOTE THE PASSAGE

I want to see the word "superior" used explicitly or a synonym or a clear implication.

If you look at what I wrote you will not find one instance of me accusing the HHMI press of trying to slant their article or try to put a spin on it' date=' nor am I accusing the researchers of being racist. Perhaps you have a problem with the word implied. I am referring to the researcher’s comments about the correlation between the emergence of the popular polymorphic forms and the emergence of culture and civilization. If I said "In the case of Microcephalin, the origin of the new variant coincides with the emergence of culturally modern humans," wouldn't you say that I am implying that Microcephalin had something to do with the emergence of culturally modern humans or vice versa? That's a direct quote that you wanted by the way. This is what I have a problem with.

 

As far as the implication of superiority, look at these:

In earlier studies of non-human primates and humans, Lahn and his colleagues determined that both Microcephalin and ASPM showed significant changes under the pressure of natural selection during the making of the human species. “Our earlier studies showed that Microcephalin showed evidence of accelerated evolution along the entire primate lineage leading to humans, for the entire thirty to thirty-five million years that we sampled,” he said. “However, it seemed to have evolved slightly slower later on. By contrast, ASPM has evolved most rapidly in the last six million years of hominid evolution, after the divergence of humans and chimpanzees.”

 

The evidence that Microcephalin and ASPM were evolving under strong natural selection in the lineage leading to humans led Lahn and his colleagues to consider exploring whether these two genes are still evolving under selection in modern human populations. “In the earlier studies, we looked at differences that had already been set in the human genome,” he said. “The next logical question was to ask whether the same process is still going on today, given that these genes have been under such strong selective pressure, leading to the accumulation of advantageous changes in the human lineage. If that is the case, we reasoned we might be able to see variants within the human population that are rising in frequency due to positive selection, but haven't gone to completion yet.”

 

So they have identified two genes related to brain size and possibly cognition and that are important to the differences between human and chimpanzee brains. Then they looked for further changes in the human population of the same genes.

While the roles of Microcephalin and ASPM in regulating brain size suggest that the selective pressure on the new variants may relate to cognition

Their analysis indicated that for each of the two genes, one haplogroup occurs at a frequency far higher than that expected by chance, indicating that natural selection has driven up the frequency of the haplogroup.

 

 

Their statistical analysis indicated that the Microcephalin haplogroup D appeared about 37,000 years ago, and the ASPM haplogroup D appeared about 5,800 years ago - both well after the emergence of modern humans about 200,000 years ago. “In the case of Microcephalin, the origin of the new variant coincides with the emergence of culturally modern humans,” said Lahn. “And the ASPM new variant originated at a time that coincides with the spread of agriculture, settled cities, and the first record of written language.

 

So now they found two variations of the genes involved in cognition and one variation is more prevalent than the other variation and they believe that the popular version was selectively chosen by natural selection. Furthermore, the frequency of new variations of genes that codes for cognition that have been selectively chosen are found in Europe and Asia, but not sub-sahara Africa.

 

I'm not sure how the implication that the European/Asian variations of these genes endow some sort of cognitive superiority that allows for better culture and civilization could be any clearer.

 

“What we can say is that our findings provide evidence that the human brain, the most important organ that distinguishes our species, is evolutionarily plastic,” he said. Finding evidence of selection in two such genes is mutually reinforcing, he pointed out. “Finding this effect in one gene could be anecdotal, but finding it in two genes would make it a trend. Here we have two microcephaly genes that show evidence of selection in the evolutionary history of the human species and that also show evidence of ongoing selection in humans.”

Lahn emphasized that it would not be correct to interpret the findings as indicating that one ethnic group is more “evolved” than another. Any differences among groups would be minor compared to the large differences in such traits as intelligence within those groups, he said. “We're talking about the average impact of such variants,” he said. “We still have to treat each individual as an individual. Just because you have one gene that makes you more likely to be a little taller, doesn't mean you will be tall, given the complex effect of all your other genes and of environment.” Lahn also said that a multitude of other genes likely exist that influence brain size and development, and further research could reveal far more complex effects of natural selection on such genes.

This is really what he is saying in the bolded area "Just because you have one gene that makes you more likely to be a little smarter, doesn't mean you will be smart, given the complex effect of all your other genes and of the environment." I'm not sure it could be any clearer that he is implying that the two genes that he studied affect cognition and that the popular European/Asian variation is a version that is more likely to make you smarter or superior than the other variation, all other things being equal. Also, I have already supplied a quote where he relates his genes to improved ability to create culture and civilization. How could that not be considered superior if we are talking about humans?

 

If you can show them being unscientific and value-loaded and quote a passage (not just your own philosophical reasoning) then if it looks objectionable to me then I will write them about it.

Why would I suggest that the publication was being unscientific? It's scientists that need to follow the scientific method and back up their claims with evidence. I am not claiming that there is anything wrong with the article; I am claiming that the scientist that they quoted is making claims that his research can't back. The fact that they found these genes that are related to microcephaly' date=' identified a great evolutionary changes from apes to humans, and have identified variations within the human population all seem very scientific to me. The problem lies with these statements:

 

"Their analysis indicated that for each of the two genes, one haplogroup occurs at a frequency far higher than that expected by chance, indicating that natural selection has driven up the frequency of the haplogroup."

There are a variety of reasons why one variation of a gene will be more widespread or popular than another; natural selection is not the only means. Asians have hair follicles that have different numbers of groupings of hairs than Europeans, but I don't believe that natural selection had any real influence on this. There are thousands of other examples of genes with variations with varying frequencies and ubiquitousness that seem to have little to do with natural selection.

 

Their statistical analysis indicated that the Microcephalin haplogroup D appeared about 37,000 years ago, and the ASPM haplogroup D appeared about 5,800 years ago - both well after the emergence of modern humans about 200,000 years ago. “In the case of Microcephalin, the origin of the new variant coincides with the emergence of culturally modern humans,” said Lahn. “And the ASPM new variant originated at a time that coincides with the spread of agriculture, settled cities, and the first record of written language.

What the hell is this guy talking about? 37,000 years ago coincides with the emergence of culturally modern humans? If you want I can provide evidence of human culture from 75,000 years ago or a great explosion of art around 20,000 years ago so that he could claim that whatever period that his variation emerged it coincided with culturally modern humans. There are examples of culture all over the timeline from up to 77,000 years ago with various kinds of statues, cave paintings or what have you in various parts of the world. Pretending that it exactly coincides with his studies is just ridiculous.

 

And another thing, I'm not sure what he did exactly to determine the timeframe that these variations emerged, but I from what I know of mutational studies you can't really predict an exact time. If there were any means to verify it I would bet everything I have that the variation did not emerge exactly 35,000 years ago. Those kinds of studies can usually only predict a very general range of time that it might have emerged and trying to strap that together with the emergence of culture and civilization is wishful thinking and has nothing to do with science.

 

if you cannot quote the HHMI press release, then fine

I wont waste any more time with this

I provided the quotes to back up my argument, but if you really want to get into this then make a challenge, something to the effect "Microcephaly and ASPM have a strong correlation to the emergence of culture and civilization respectively, and the only plausible means of the emergence of the variations that we observe in the human populations is due to natural selection," and I will disagree and accept the challenge.