Modern humans may have inherited some Neanderthal genes

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I know virtually nothing about this subject, and I will try very hard to avoid odious comparisons between Neanderthals and anyone else, but it appears that white and Asian people, but not sub-Saharan Africans, have 1-4% Neanderthal genes in our genomes. You may read news articles about it in the New York Times free or in Science with a subscription. Science also has provided a special feature on the Neanderthal genome and has made two technical articles available without charge, but not the news article cited above. This paragraph has almost completely exhausted my knowledge of the Neanderthal genome.

131 Comments

So, Neanderthals were not human beings and contamination was not an issue. Glad that’s finally settled. Now the real fun can start.

Did Neanderthals have the same chromosome complement as chimpanzees, or did they have the same fusion seen in humans? Their mitochondrial DNA is intermediate between chimps and humans as is their nuclear DNA, but how many SINE insertions do they share in common with humans? Can the Neanderthal nuclear DNA found to be introgressed into modern humans be used to study human adaptation and migration? How will this compare to the mitochondrial and Y chromosome data? What regulatory changes were important in the evolution of human morphology and which occurred before the split with Neanderthals? Can mitochondrial and nuclear sequencers be obtained from even older hominid fossils and how will they compare to the Neanderthal sequence? How are the creos ever going find a way to spin this that doesn’t make them look bad? They must live in constant fear of things like this being discovered.

This comment has been moved to The Bathroom Wall.

This discovery is additional confirmation of the “Out of Africa” migration hypothesis, since Africans lack traces of the Neanderthal genome (Current Africans were not part of the migration out of Africa which allowed Homo sapiens to populate Europe, Asia, and eventually, Australia and the Americas.). This discovery also confirms possible skeletal evidence of hybridizations between Homo sapiens and Homo neandertalensis in the Middle East, where their skeletons have been found, often in the same sedimentary strata.

Not surprisingly, Carl Zimmer has an especially lucid account of this discovery, made primarily by Swedish geneticist Svante Paabo and his team at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany:

http://blogs.discovermagazine.com/l[…]and-genomes/

So this explains the Tea Party!

I thought that earlier mitochondrial DNA analysis ruled out the interbreeding hypothesis?

Not even remotely close:

Diogenes said:

So this explains the Tea Party!

If you want an explanation for the Tea Party Movement, then read Brown University historian Gordon Wood’s excellent histories (which, I am sure, Ken Miller would endose immediately, since he has done so already in his “Only A Theory: Evolution and the Battle for America’s Soul”), or read the original material from the likes of John Adams, Benjamin Franklin, Thomas Jefferson, James Madison and their fellow Founding Fathers.

If you want to discuss politics, then please do so elsewhere. Your comment isn’t informative, especially as it pertains to the Science articles cited by Matt Young.

That’s an excellent point, Wheels, but this study didn’t rely on mitochondrial DNA data (which Carl Zimmer does mention in his extremely lucid, quite well written, report), but instead, by studying the entire genome:

Wheels said:

I thought that earlier mitochondrial DNA analysis ruled out the interbreeding hypothesis?

I heard Svante Paabo talk about this during a special two day symposium on evolution held exactly two years ago at Rockefeller University. He said that he and his team was close to creating a complete Neanderthal genome sequence, but I didn’t really grasp that he was really very, very close.

Wheels said:

I thought that earlier mitochondrial DNA analysis ruled out the interbreeding hypothesis?

No, It did not rule it out. It only provided evidence that there was no extensive hybridization involving female Neanderthals mating with human males. That certainly did not preclude the possibility of low levels of hybridization, especially between human females and Neanderthal males. This evidence seems to indicate that some low level of introgression of Neanderthal genes happened in Europe after modern humans started coming out of Africa and before they colonized the rest of the world. That is certainly consistent with all of the other genetic data.

Probably more likely in the Middle East, since some fossilized hominid remains indicate hybridization between both species. To the best of my knowledge, that’s the only region where there may be paleobiological evidence of hybridization:

DS said:

Wheels said:

I thought that earlier mitochondrial DNA analysis ruled out the interbreeding hypothesis?

No, It did not rule it out. It only provided evidence that there was no extensive hybridization involving female Neanderthals mating with human males. That certainly did not preclude the possibility of low levels of hybridization, especially between human females and Neanderthal males. This evidence seems to indicate that some low level of introgression of Neanderthal genes happened in Europe after modern humans started coming out of Africa and before they colonized the rest of the world. That is certainly consistent with all of the other genetic data.

It’s the Middle East as the likely site for introgression of Neanderthal genes simply because much of Europe was probably covered by continental glaciation, and early Homo sapiens would have had to trek north and west from the Middle East to reach what is now Western Europe; from Asia, migrants would have headed due north and east.

John Kwok said:

Probably more likely in the Middle East, since some fossilized hominid remains indicate hybridization between both species. To the best of my knowledge, that’s the only region where there may be paleobiological evidence of hybridization:

DS said:

Wheels said:

I thought that earlier mitochondrial DNA analysis ruled out the interbreeding hypothesis?

No, It did not rule it out. It only provided evidence that there was no extensive hybridization involving female Neanderthals mating with human males. That certainly did not preclude the possibility of low levels of hybridization, especially between human females and Neanderthal males. This evidence seems to indicate that some low level of introgression of Neanderthal genes happened in Europe after modern humans started coming out of Africa and before they colonized the rest of the world. That is certainly consistent with all of the other genetic data.

This is truly amazing to me, since neanderthals have 24 pairs of chromosomes and we have 23. This shows a lot more ability to breed when there are differences between genomes. Have they said anything about how this sheds light on when and how our chromosomes fused together?

detailed discussion of the paper here: http://johnhawks.net/weblog; also see http://dienekes.blogspot.com for a skeptical perspective

Why do you say that Neandertals had 24 pairs of chromosomes? Presumably, for a viable hybrid to prove viable, the chromosome number must be the same? 23?

Gary said:

This is truly amazing to me, since neanderthals have 24 pairs of chromosomes and we have 23. This shows a lot more ability to breed when there are differences between genomes. Have they said anything about how this sheds light on when and how our chromosomes fused together?

Small and outbreeding ethnic groups of homo sapiens are going extinct these days (mostly indigenous peoples). But are they truly going extinct when their DNA is still around? The idea that neanderthals didn’t shuffle off without leaving a mark on us really appeals to me, in that I have an emotional need to see slivers of hope in the Holocene Extinction.

Within my species I’d like to see a similar project: Find DNA from extinct Indian tribes, isolate any unique areas of it, and compare to living people in the USA. Did they leave a mark?

Another point of curiosity as an artist with an interest in the cosmetic differences of race - Could the genes responsible for neanderthal skeletal features be discovered, then compared against modern groups that look similar? Example: Many French and Chinese people receding chins, which is a classic neanderthal feature. Did they inherit them from our extinct cousins?

Given what I’ve seen of the study (I’ll need to read it more deeply, time permitting), it’s safe to assume most white people are part neanderthal. That’s fun to know about oneself, really.

This is all very unscientific and useless reflection, so apologies to anyone annoyed by it. Carry on.

Malchus and Gary–

PZ Myers has a really good post explaining how two individuals with different numbers of chromosomes can produce offspring. See his post “Basic: How Can Chromosome Numbers Change?” April 21, 2008, on Pharyngula.

The gist of it is, two individuals with different numbers of chromosomes have reduced fertility, but reduced fertility doesn’t mean no fertility.

Well CS, while your goal of DNA comparison is laudable, I am afraid that it might meet with ample resistance from American Indian tribes, especially those who fear they could lose their protected status on reservation lands, if, for example, it could be shown that much of the surrounding population had genes from these tribes and were far more numerous than the surviving tribes:

CS Shelton said:

Within my species I’d like to see a similar project: Find DNA from extinct Indian tribes, isolate any unique areas of it, and compare to living people in the USA. Did they leave a mark?

Another point of curiosity as an artist with an interest in the cosmetic differences of race - Could the genes responsible for neanderthal skeletal features be discovered, then compared against modern groups that look similar? Example: Many French and Chinese people receding chins, which is a classic neanderthal feature. Did they inherit them from our extinct cousins?

The presence of receding chins amongs those of my ethnic background (I am of Chinese descent) and the French may have occurred for reasons other than traces of Neanderthal DNA, based, I suppose, on local environmental factors and long-term reproductive isolation.

I was reading this study last night. The problem here is that unsavory origins of Westerners is in conflict with the overwhelming evidence of good performance, health outcomes, scientific progress, etc., from the West. In fact, if we come from Neanderthals, how did we ever get where we are? An ancillary question arises: If we have these defective genes, how did we ever figure it out?

NS

Why do you think that Neanderthals were “unsavory” or “defective”? Or that the “west” is representative of modern Homo sapiens, or of what is “savory” or not “defective”?

notedscholar said:

I was reading this study last night. The problem here is that unsavory origins of Westerners is in conflict with the overwhelming evidence of good performance, health outcomes, scientific progress, etc., from the West.

The only person here saying that Westerners having an unsavory origin is a problem is you. If this is the conclusion you have come to, it appears that you have extremely poor reading comprehension skills. The gist of the report can be neatly summarized in the title of this blog post. A less concise version would be “The ancestors of modern Caucasians apparently interbred with Neanderthals prior to the Neanderthals’ extinct.” Nothing about racial inferiority or racism in general.

In fact, if we come from Neanderthals, how did we ever get where we are? An ancillary question arises: If we have these defective genes, how did we ever figure it out?

NS

The answer is quite simple: either the genes we humans inherited from Neanderthals were not defective, or they were defective in a way that doesn’t bother us at all.

Either way, given as how Homo sapiens has been able to persist for thousands upon thousands of years after the extinction of H. neanderthalensis strongly suggests that your concerns that we inherited “defective genes” from them are foolish and irrelevant.

Notedtroll:

The problem here is that unsavory origins of Westerners is in conflict with the overwhelming evidence of good performance, health outcomes, scientific progress, etc., from the West. In fact, if we come from Neanderthals, how did we ever get where we are?

Are you trying to be stupid or what?

You are assuming Neanderthals were markedly inferior to ancient H. sapiens. There is little evidence for this. Their lineage survived for 400,000 years in ice age Eurasia, while we were stuck in Africa. One could argue that they were tougher and better adapted to a very severe environment for humans than we were. We only managed to colonize that area late in our history.

There is also the well known genetic phenomena of hybrid vigor. Outbreeding groups of organisms with high degrees of heterozygosity tend to be fitter than inbred groups. That is why you are not supposed to marry your sister or cousin. It is also the basis of our agricultural systems. Hybrid corn is one of the most important crops in the USA and the world.

Besides which, the hybridization was 40,000 years ago. Time enough for significant evolution after the fact, which we’ve seen in humans.

You are not a noted scholar, but rather a garden variety troll.

Not just Caucasians, Stanton. Your quote should be, “The ancestors of modern non-African Homo sapiens apparently interbred with Neanderthals tens of thousands of years prior to the Neanderthals’s extinction”:

Stanton said:

notedscholar said:

I was reading this study last night. The problem here is that unsavory origins of Westerners is in conflict with the overwhelming evidence of good performance, health outcomes, scientific progress, etc., from the West.

The only person here saying that Westerners having an unsavory origin is a problem is you. If this is the conclusion you have come to, it appears that you have extremely poor reading comprehension skills. The gist of the report can be neatly summarized in the title of this blog post. A less concise version would be “The ancestors of modern Caucasians apparently interbred with Neanderthals prior to the Neanderthals’ extinct.” Nothing about racial inferiority or racism in general.

In fact, if we come from Neanderthals, how did we ever get where we are? An ancillary question arises: If we have these defective genes, how did we ever figure it out?

NS

The answer is quite simple: either the genes we humans inherited from Neanderthals were not defective, or they were defective in a way that doesn’t bother us at all.

Either way, given as how Homo sapiens has been able to persist for thousands upon thousands of years after the extinction of H. neanderthalensis strongly suggests that your concerns that we inherited “defective genes” from them are foolish and irrelevant.

You are sadly quite delusional here, noted ignoramous:

notedscholar said:

I was reading this study last night. The problem here is that unsavory origins of Westerners is in conflict with the overwhelming evidence of good performance, health outcomes, scientific progress, etc., from the West. In fact, if we come from Neanderthals, how did we ever get where we are? An ancillary question arises: If we have these defective genes, how did we ever figure it out?

NS

You are conflating cultural traits of Westerners with biological ones. And, moreover, if Neanderthals were truly inferior, then why did they not only persist, but also thrived, during the worst instances of continental glaciation in Europe, and apparently, continued to survive for tens of thousands of years after encountering migrating modern Homo sapiens from Africa?

No need to belabor the point, but I concur completely with TomS’s, and especially, Stanton and raven’s comments.

wikipedia Neanderthals:

Neanderthal cranial capacity is thought to have been as large as that of Homo sapiens, perhaps larger, indicating that their brain size may have been comparable as well. In 2008, a group of scientists made a study using three-dimensional computer-assisted reconstructions of Neanderthal infants based on fossils found in Russia and Syria, showing that they had brains as large as ours at birth and larger than ours as adults.[10]

I’ll add here that Neanderthals had larger brains than us. Intelligence isn’t highly correlated with brains size but the correlation isn’t zero either.

So this explains the Tea Party!

Oh, come on. I tried soooo hard to avoid saying something like that!

notedscholar -

Your comment is a remarkable example of bias leading to miscomprehension.

I was reading this study last night. The problem here is that unsavory origins of Westerners

“Westerners” is a modern term describing cultural traits.

The article does not deal with the “origins” of any group of people. It notes some small amount of overlap of genes between European and Asian populations, with the recently sequenced Neanderthal genome.

“Unsavory” is a subjective term which you have no rational basis for using here. You seem to be projecting present day biases of your own onto a poorly understood species of humans who went extinct (albeit while seemingly passing on some amount of genetic material to modern humans) 28,000 years ago.

is in conflict with the overwhelming evidence of good performance, health outcomes, scientific progress, etc., from the West.

No-one said anything at all about any of this. I will note that the only comment so far that may reflect a lack of respect for scientific progress is yours.

In fact, if we come from Neanderthals, how did we ever get where we are?

The article cannot be interpreted by a competent reader as suggesting that we “come from” Neanderthals. (The use of the unscientific terminology “come from” is associated with some of the worst creationist arguments, even if you are not implying acceptance of those arguments).

You seem to be taking some kind of modern biases, and using them to make bizarre negative judgments about an extinct species of human. We don’t know what type of descendants might have hypothetically evolved from Neanderthals in alternate circumstances.

An ancillary question arises: If we have these defective genes,

There is no scientific rationale for labeling Neanderthal genes “defective”.

Note that how many genes we “share” with Neanderthals depends entirely on how we define the identity of genes. It is very accurate to state that we share many genes with brewer’s yeast. In this thread about modern humans and Neanderthals, gene identity is being defined, not by broad functional and sequence homology (and related traits), but by sufficiently tight homology to imply fairly recent common ancestry. From the point of view of functional homology, we share the all but a tiny fraction of our genes with Neanderthals and chimpanzees.

Malchus said:

Why do you say that Neandertals had 24 pairs of chromosomes? Presumably, for a viable hybrid to prove viable, the chromosome number must be the same? 23?

The basic genetics must be similar, but individual chromosomes can, and do, split and fuse sometimes so that closely related species can still have the same basig genome sliced up into different numbers of chromosomes.

In such a case these animals can sometimes interbreed despite the different number of chromosomes, as evinced by hybrids such as the mule, an animal with (typically) 63 chromosomes, the offspring of a donkey (64 chromosomes) and a horse (62).

On the other hand, though sometimes these hybrids are very successful (mules, in general, are more robustly healthy and intelligent than either horses or donkeys), the ad-hoc nature of their genetics usually renders them infertile.

harold said:

notedscholar - An ancillary question arises: If we have these defective genes,

There is no scientific rationale for labeling Neanderthal genes “defective”.

Indeed. It should be noted that Neanderthals have a much longer track record than modern humans. They ruled as the dominant species in northern Europe for 400,000 years while many variations of our more direct ancestors proved too delicate to endure.

Wasn’t this documented in Clan of the Cave Bear with Daryl Hannah?

First reactions from AiG:

The news doesn’t surprise young-earth creationists, who predicted overlap between modern human and Neanderthal genomes. Based on Scripture, creationists consider Neanderthals to have been fully human, descendants of Adam and Eve (through Noah), and therefore they would have lived in the same time and place as other humans. But factors related to both the dispersion at Babel and environmental pressures afterward resulted in people groups with different physical characteristics, including humans with “Neanderthal” characteristics.

Liberty University cell biologist (and creationist) David DeWitt called the research an “amazing feat” of science that supports creationist expectations. “Finding Neanderthal DNA in humans was not expected by evolutionists, but it was predicted from a creation standpoint because we have said all along that Neanderthals were fully human: descendants of Adam and Eve, just like us,” he told News to Note.

DeWitt also pointed to research on mitochondrial DNA several years earlier that had boldly claimed that Neanderthals were not our ancestors, based on the genetic results at that time. “We really have to be careful with scientific conclusions and data,” DeWitt explained. “Now, with a more thorough analysis, we have the exact opposite conclusions.”

While Neanderthals remain something of a mystery even to creationists, the new research reminds us of the reality of what the Bible teaches: Neanderthals were neither ape-men nor inferior to other humans. Rather, as with all humans, Neanderthals were part of the one blood of humankind (Acts 17:26), and therefore carried the image of God (Genesis 1:27).

* As to why the percentage of Neanderthal DNA found in modern humans is relatively small, we note the following. Neanderthal fossils are from individuals who have been dead for hundreds to thousands of years. Since that time, there have been selection pressure, genetic drift, and population bottlenecks (such as the bubonic plague that struck Europe, episodes of “ethnic cleansing,” etc.). These all have impacts on the gene pool, as does relative population size. Humans alive today have come through that, while the Neanderthals did not.

So there you have it. Something YECs appaarently knew all along.

The human telomere is a hexamer (TTAGGG) repeated thousands of times. and

I am a cumulonimbus of doubt that centromere sequence can be obtained from Neanderthal remains.

evolutionpages.com:

The telomere sequence is highly conserved in different groups of organisms. For example vertebrates have the sequence TTAGGG repeated many times. (In primates the sequence is repeated 500 to 3500 times). Adjacent to the telomere, are regions with other DNA repeats (known as Telomere Associated Repeats) but these regions, rather than being highly conserved, are highly polymorphic - that is they have many variations even within the same species. Nevertheless the pretelomeric region can be easily recognised in closely related species. Occasionally genes are found in the pretelomeric region.

1. Not necesarily thousands of repeats for telomeres. Hundreds to thousands according to evolutionpages.com. And the chromosome 2 fusion is not a telomere. It is the remnants of two telomeric regions fusing and it appears to be old, possibly millions of years old based on the divergence of chimp centromere 2q. Without looking on the human sequence (too busy right now), it is likely to be shorter than the original two telomeres and have a lot of mutations from just TTAGGG repeats.

2. A prediction is that the TTAGGGCCCTAA sequence should be in the Neanderthal genome.

3. Another prediction is that the diverged, nonfunctional remnant of chimp 2q centromere should also be there. One doesn’t have to sequence megabases of DNA to see if diagnostic fragment sequences are there or not and compare them to human and chimp sequences.

4. They used a microarray technique recently developed to fish out specific regions to sequence in samples that are heavily contaminated with other DNA. Ann Gibbons: “In a separate paper (p. 723), the team describes and successfully tests a new method for filling in gaps in the rough draft of the genome.”

There are predicted sequences that should be present if Neanderthals are 23 pairs of chromosomes. The tools for this sort of sequencing project are very powerful and one can use them to fish out regions for sequencing. Sequencing Neanderthals which are so closely related to humans (99.84% in Ann Gibbons) is more like resequencing than sequencing.

I can see a lot of ways to try and sequence these regions and wouldn’t hesitate to try them all. Never know until you give it a try.

We will just have to disagree, but even the Neanderthal sequence groups thought it was somewhere between difficult and impossible a few years ago to get a genomic sequence. Underestimating science is common and commonly wrong.

Was busy last night with a few friends attending a memorial tribute to one of our greatest photographers:

amyc said:

John Kwok said:

Who said I’m a liberal? Apparently you haven’t heard of my “affection” for a certain American president and two of his closest aides, who, unfortunately, are fellow alumni of our high school.

Anyway I was concerned that this thread might digress into more political baiting that’s occurred elsewhere here at PT, and thought that given the historic importance of this report on the “rough draft” of the Neanderthal genome, didn’t want to see any similar incidents here.

I think he meant libertarian. How are you doing tonight john?

So, in a sense, you could say I was at a wake, especially when, after that memorial tribute, I ventured into the same bar, where, back in July, I attended an impromptu wake with two hundred other former students of a certain well known memoirist. By mere coincidence, I found myself sitting next to a color photo of my “father”, while talking with my photographer friends last night.

Apparently others have been listening since they haven’t been talking about a certain demented creo from north of the border:

utidjian said:

John Kwok said:

I decided that the best course would be trying to ignore him as much as possible and would advise others to follow in my wake:

Matt Young said:

You. Moron. … Idiot.

No more than one response each to Mr. Byers, please, and keep them civil. Further responses will find themselves on the Bathroom Wall.

John,

You leave a wake?

I hadn’t noticed ;)

-DU-

Diogenes said:

amyc said: Most creationists don’t believe they are lying. The ones you talk about are the famous ones: they write books and give speeches and such. These people know what they are doing, and are called liars (rightly so).

…Some “civilian” creationists (as I like to call them) don’t even realize they are creationists or label themselves as such. …I don’t believe that “civilian” creationists are liars, because they truly don’t know any better. They are “inadvertent liars.”

Yeah, I get the distinction between “civilians” who know little science and can’t be blamed, and “generals” who know some science, cherry-pick data, ignore contrary evidence, and make stuff up. I get that.

Of course I have “civilians” in my family, close to me. I was indirectly informed I am no longer godfather to my niece and nephew.

But it’s the “generals” I don’t understand. They know they’re making stuff up. Would it kill Duane Gish to admit the bullfrog protein didn’t exist? *Why* did William Dembski lie about the probabilities he calculated in “No Free Lunch”? What are they so scared of?

I mean, they all worship the Bible, literally. Like it’s so great, you have to worship it, twist facts if you have to to defend it, lie, whatever. What’s the appeal? Is the Bible that great? Right now I’m involved in a back-and-forth argument with a creationist blogger about whether rape and sex slavery are sanctioned in the Bible. Oh, they say they believe in a literal interpretation, but heaven forbid you should point out the literal descriptions of genocide, rape, infanticide, and slavery. Then they’ll fight tooth and nail.

So what motivates this visceral desire to defend Biblical literalism?

Two theories:

A. Is it just moral terror? The fear that without God giving us his word in book form, the rational thing to do would be to go about a-killing and a-raping?

B. Is the observation that there are people different from myself– who listen to music I don’t like, vote for politicians I don’t like, dress in ways that I don’t like– and there must be a cause for all this– that they don’t share my religious beliefs? So if I convert everybody to my religion, no longer will there be human behaviors I can’t figure out, because they’ll all act like me.

Christianity is an evolving meme which speciates to occupy every niche available to it in human minds. Since it doesn’t have to have even a tenuous connection to reality, the only limit to the form it can take is whether or not there is anyone willing to believe it. Thus it is inevitable that sects based on biblical literalism are going to exist, and since it is absolute “truth” people will go to any lengths to defend it.

it’s understood that the civilians lie inadvertently; they don’t know what’s true and they aren’t exactly encouraged to develop the thinking skills to work it out.

in the case of people who should know better, it’s noteworthy that lying carries different moral values for the two sides in this case. it was previously mentioned that creationist belief is top down. in a bottom up system, true statements are links in a theoretical structure, and a mistaken fact poisons the whole structure and the conclusions. so in the science world,it’s rather disgraceful to risk being mistaken. but in the top down world, a wrong claim might still be performing the honorable function of convincing people of the truth. a trial and error approach is ok because you’re searching for anything that sticks … it’s the (moral) responsibility of the “complainers” to cut away arguments that don’t work.

I don’t think the human-bullfrog thing started out as a lie. I think there really was a very early study where bullfrog DNA was contaminated by DNA from one of the research team. But the scientists corrected the mistake at least a quarter of a century ago.

Somehow the creationists can convince themselves they’re not “really” lying if they quote something a biologist or paleontologist said once–no matter how far the statement is from current scientific thought.

Genome Res. 2007 Oct;17(10):1420-30. Epub 2007 Sep 4.

Biased clustered substitutions in the human genome: the footprints of male-driven biased gene conversion. Dreszer TR, Wall GD, Haussler D, Pollard KS.

Department of Biomolecular Engineering, University of California, Santa Cruz, California 95064, USA.

Abstract We examined fixed substitutions in the human lineage since divergence from the common ancestor with the chimpanzee, and determined what fraction are AT to GC (weak-to-strong). Substitutions that are densely clustered on the chromosomes show a remarkable excess of weak-to-strong “biased” substitutions. These unexpected biased clustered substitutions (UBCS) are common near the telomeres of all autosomes but not the sex chromosomes. Regions of extreme bias are enriched for genes. Human and chimp orthologous regions show a striking similarity in the shape and magnitude of their respective UBCS maps, suggesting a relatively stable force leads to clustered bias. The strong and stable signal near telomeres may have participated in the evolution of isochores. One exception to the UBCS pattern found in all autosomes is chromosome 2, which shows a UBCS peak midchromosome, mapping to the fusion site of two ancestral chromosomes. This provides evidence that the fusion occurred as recently as 740,000 years ago and no more than approximately 3 million years ago. No biased clustering was found in SNPs, suggesting that clusters of biased substitutions are selected from mutations. UBCS is strongly correlated with male (and not female) recombination rates, which explains the lack of UBCS signal on chromosome X. These observations support the hypothesis that biased gene conversion (BGC), specifically in the male germline, played a significant role in the evolution of the human genome.

It should be possible to estimate when the human chromosome 2 fusion occurred. A knowledge of mutation rates in noncoding freely evolving DNA and the sequences of chimps and humans should be enough.

One estimate is above, 740 to 3,000 kyears. Neanderthals are thought to have split from us at most 400 kyears ago.

Science fiction books might not be all that useful for obtaining scientific information.

hoary puccoon said:

As was demonstrated by a poster above, another creationist mantra is that science is continually changing its conclusions, therefore none of it is right.

The ability to adapt to new evidence is, of course, the basis and great strength of science. But in this case, as in many others, the amount that science actually changed its conclusions is largely in the minds of newspaper headline writers. Everyone working in the field seemed to be aware that the lack of Neanderthal genes in modern human mitochondria didn’t necessarily mean there were no Neanderthal genes in modern human nuclear DNA. So this study wasn’t so much correcting an error as refining a somewhat fuzzy picture.

I think you mean me. No. Not science is wrong. Science is susposed to be a more prestiges level of conclusions means of a higher lever of process before conclusions are announced. This case shows how origin subjects are not science ones. They change conclusions easily with new data making previous conclusions “science’ questionable. Adapting to new evidence should not be happening in science like this. Theories are too be well supported. Einstein didn’t add new info to Newton but rather a greater conclusion was drawn with new data. Its different.

As for the claim this is not a correction well its presented as new from previous ideas. Seems like a correction. I don’t know what the textbooks of last year say.

eric said:

djlactin said: My point was that European caucasians (excluding caucasians currently living in India, who have been selected for darker skin – carcinomas and such) are starkly different from, shall I say, “typical” humans.

Here’s one possible explanation for it. Short summary: the Atlantic gulf stream makes it possible to grow grains in high European latitudes. This is a great benefit in terms of food availability, but a grain-based diet does not provide much vitamin D, so paler skin becomes more of an advantage. Without the gulf stream, no grain. Without the grain, scandinavians etc…would probably have the skin tone of inuit.

Or so the web site says. Its not a peer-reviewed publication but sounds like a reasonable hypothesis to me.

There is no need for gulf streams. Simply lack of pigmentation is from a need to deal with a original and still cloudy world there in Europe. The more cloudy the the less pigmentation in skin, hair, eyes, An example is the most extreme redheaded people. They are redhead for the same reason they have red spots and very white/non tanning skin. The pigmentation is so rejected by the body it must squeeze every bit into spots/hair. Likewise redheaded people have the least hair count of Europeans and the men often don’t need to shave much in a week. of coarse simply the body doesn’t need hair in the way of the sun rays poking through the clouds. Its all about the sun.

Here it is the wee small hours of the morning over most of Canada, and here’s Byers, regurgitating nonsense again. Do the voices in his head keep him awake, or something?

Just ignore him, Dave. He’s simply craving for attention. One wonders how he can perform adequately as a dedicated civil servant on behalf of his Canadian province:

Dave Luckett said:

Here it is the wee small hours of the morning over most of Canada, and here’s Byers, regurgitating nonsense again. Do the voices in his head keep him awake, or something?

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This page contains a single entry by Matt Young published on May 7, 2010 8:33 PM.

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