Humanity's Genetic Diversity on the Decline

jd writes "In a study covering five different periods of history, from 300 AD to the present day, and geographically spread across much of Europe, scientists have extracted the mitochondrial DNA from a sizable number of individuals in an effort to examine changes in diversity. The results, published in the Royal Society journal is intriguing to say the least. 1700 years ago, three out of every four individuals belonged to a different haplotype. In modern Europe, the number is only one in three. The researchers blame a combination of plague, selection of dominant lineages and culturally-inflicted distortions. The researchers say more work needs to be done, but are unclear if this involves archaeology or experiments involving skewing the data in the local female population."

Is this news?

Isn't this basically what that whole "survival of the fittest" thing does? End less suitable genetic traits and combine the surviving ones in an ever repeating cycle, ever closer to the "fittest" genetic blend?

Re:Is this news?

"Isn't this basically what that whole "survival of the fittest" thing does?"

Their conclusions are not valid for all of humanity anyway. How does Western Europe equal humanity? It is already known [sciencedaily.com] that there is less genetic diversity in two Europeans from different countries than there is in two Africans from the same village. What a Eurocentric point of view.

Re:Is this news?

I know! What a bunch of malarky. Everyone knows that North America equals humanity, not Western Europe. Duh!

Re: Is this news?

I know! What a bunch of malarky. Everyone knows that North America equals humanity, not Western Europe.

Sounds like something a Canadian would say.

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The Canadians took them...... damn canadians

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Why should anyone care about populations outside of his/her own? It's not natural to do so.

Re:Is this news?

No, it isn't. For one thing, diversity is itself a survival trait in a population -- a population that had actually all zeroed in on the one single 'most fit' genotype would be terribly vulnerable.

It's misconceptions like these that make it easier for cranky American Protestants to think of 'Evolutionism' as just another faith.

Re:Is this news?

Nobody said "fittest" is an absolute, nor even measurable. It just means "whatever has the best chance of survival in this environment". If any variable changes (such as the environment), it's likely some other trait becomes more "fit". As such; in an environment that changes rapidly, a more diverse genetic will have bigger chances, in a more stable environment, genetic markup would have the time to zero in on a particular direction. This vulnerability you describe only exists when one of the variables changes. Diversity may be (and probably is) a better trait in the long term, but in the short term it serves little purpose. There's probably millions of times in the past where diversity in human genes has grown, we happen to live in a time and environment that is stable enough for other traits to become more important than diversity and so these other traits tend to be the ones with the biggest chance of survival.

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While seriously defective individuals, at least from a genetic perspective, are able to lead long lives in many cases because of technology and wealth, their reproductive success probably still isn't up to par. And that's really what fitness measures, not

Re:Is this news?

While you are indeed a prime example of what you describe, I don't think the issue is as widespread as you suggest.

Re:Is this news?

"It's just that it's a theory based on the NON-existence of a creator."

Not at all. Me thinks you do not understand the concept of scientific reasoning as well as one might hope. It is a theory 'not based on the existence of a creator', which is a far cry from 'a theory based on the NON-existence of a creator'. Not assuming the existence of a 'creator' (whatever one may choose to mean with that) one does ones best to understand and explain observed phenomenon in a rational manner. While one cannot yet prove that the flying spaghetti monster does or does not exist through repeatable experimentation (and people should feel free to contribute their research in this area to the scientific community as a whole), one can make a very good description of the functioning of the world around us without having to tackle the issue of the influence of his omnipotent noodly appendages.

Re:Is this news?

I went to a US public school where our principal told the senior class that we were damn well going to go to a prayer session before graduation or we wouldn't get our diplomas, despite a Supreme Court ruling the same year that held that even holding such a ceremony was definitely illegal. Yeah, our entire school system is run by a bunch of atheist communists who hate religion. Right.

This oppression is also why it's absolutely impossible to get elected President unless you're an avowed Atheist.

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When you have a theory that explains the natural world as perfectly as evolution does, invoking a creator just because not having one makes you uncomfortable is a terrible unparsimonious thing to do. If there's a bias here, it's that science tends to favor

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You might say, "ID is stupid when there's this perfectly good scientific explanation". Well, if you regard invoking a creator as "stupid", then you've shown that you're biased against that idea, just as I am biased against the idea that the universe "just

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I would like to see any examples of predictions based on evolution. I've actually grown more skeptical of it the more I study about it. To be clear: I'm not saying I don't believe in DNA or inherited traits (that would seem crazy - even to me).

Well then l

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I believe that you can add 1 and 1 together and get 2. And that you can add 1 to that result to get three, and so on. What I'm skeptical of is that those minor changes could ever add up to a million, or to integers as diverse as 32 and 13429, or a prime

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How is it any less complex than a "part" of the universe suddenly appearing and spontaneously creating the rest? Neither has a cause. Linguistic complexity doesn't really determine causal complexity. Case in point: note that the "God theory" can be sum

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> Isn't this basically what that whole "survival of the fittest" thing does?

Actually a lot of the confusion is cleared up by thinking of it as "survival of the fit enough" instead of "the fittest".

You can roughly divide the gene pool into three categori

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Grr. Now it looks like i dropped a not and my correction is incorrect.

Okay...

IF they don't breed and the others outbreed them and then the others kill them, their decision to not breed will have been stupid (even tho everyone ultimately dies when the out-

I Can Vouch For That!

Come on down to Southern Ohio and you'll see just what I mean. The Shadow Over Portsmouth!

skewing data

The researchers say more work needs to be done, but are unclear if this involves archaeology or experiments involving skewing the data in the local female population.

In the name of science, I volunteer for any experiments involving "skewing" "data" into the local female population.

"skewing the data in the local female population."

I've never heard it called that before. Either something is missing in translation, or we should be told a bit more about what the Royal Society is like nowadays. After all, it was founded by Charles II, and he was pretty good at something that sounded a b

Re:"skewing the data in the local female populatio

Yeah, I think you mean "skewering" the local female population heh...

Seriously, genetic diversity cannot be helped by a society that favors monogamous, life-long relationships between couples. The most genetic diversity is achieved when women have children

Don't worry

Easyjet is restoring the diversity.

 

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On a serious note I've heard it argued that the ease of travel is slowing the rate of human evolution (or if you don't believe in it, human natural selection) as the chances of a even an improving mutation/trait being successful over time is much lessened

Re:Don't worry

That's hard to say. The ease of travel has been leading to a decrease in diversity within a species which is significantly less diverse than most other species already.

But as was pointed out in an article I read last year, what diversity looks like may very well be in transition. I don't personally quite buy the authors suggestion, but the trend is away from distinctive racial groups and more towards groupings based upon intellect and looks.

Which to some extent makes sense. The premium that most groups place on mating within the same group has been decreasing, at least around here, and people will always choose somebody that they find enjoyable to be around to those that are not. Frequently looks, intellect, sense of humor and health are considered selection criteria. So the idea that the groupings would be based upon that wouldn't be too outlandish.

Some points

Firstly, the article has nothing about "human genetic diversity". It's about ancient UK population having larger haplotype diversity than the many modern European populations.

There could be a few reasons to this. Anglo-Saxons came to England around 550AD. Also Romans had settled the island. Later also Vikings came. These plus the local population already implies quite a lot of diversity.

Since then some lineages have been more successful, that's it. Actually, this could be considered supporting evidence for D. Gregory Clark's hypothesis that upper classes have been replacing the lower ones during middle ages in England, as reported by Slashdot yesterday, see http://science.slashdot.org/article.pl?sid=07/08/0 7/2221256 [slashdot.org]

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I thought of the same article. We need an explanation for why genetic diversity decreased so much in Europe and not in Africa (for example). And the mechanism of the wealthy families replacing the poor is a very plausible suggestion, since it has been inde

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It may also be that certain mitochondrial variations were better adapted for a thousand years ago, while they don't hold up so well in the modern world.

Aren't mitochondria just energy converters? How much can their conditions change, deep within the c

The historic sample is kinda small

They used a historic sample of only 48 ancient Britons and those were even spread out to a timeframe from about 700 years (contrary to the summary, the ancient samples lived between AD 300 and 1000 which is a relatively big timeframe).

I would think that their analysis could still be statistically relevant, but still they say themselves that more work is needed, so I think more historic sample data would be quite useful.

It's already been explained.

It's sad that scientists don't read each other's stuff. Then again, both of these articles came out at the same time, so it would have been virtually impossible.

But the parent article refers to a phenomenon mentioned in a slashdot article about the Industrial Revolution less than a day ago. http://science.slashdot.org/article.pl?sid=07/08/0 7/2221256 [slashdot.org]

Now the key is to see if the two groups catch on.

Outliers

If they eliminated the outliers, such as West Virginia, the average human diversity would go back to what it was in 300AD.

British science geeks have it all figured out

So, as I understand it, this was written by an unattractive British science geek as a pickup line to use in bars full of attractive women.

"Hi. We analysed the historical genetic diversity of human populations in Europe at the mtDNA control region for 48 ancient Britons who lived between ca AD 300 and 1000, and compared these with 6320 modern mtDNA genotypes from England and across Europe and the Middle East. We found that the historical sample shows greater genetic diversity than for modern England and other modern populations, indicating the loss of diversity over the last millennium. The pattern of haplotypic diversity was clearly European in the ancient sample, representing each of the modern haplogroups. There was also increased representation of one of the ancient haplotypes in modern populations. We consider these results in the context of possible selection or stochastic processes. So, you understand... you... must have... sex.... with me."

"Are you trying to tell me that the genetic diversity of Britain is at stake if I don't hop into the sack with you?"

"Umm... yes."

"Yes, then. For Britannia and the queen!"

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Shouldn't that be

"Are you trying to tell me that the genetic diversity of Britain is at stake if I don't hop into the sack with you?"

"Umm... yes."

"Well, I'll just lie back and think of England [wikipedia.org], then."

? ;)

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Just lie back and think of England...
http://en.wikipedia.org/wiki/Lie_back_and_think_of _England [wikipedia.org]

All the scientific research aside...

...I blame West Virginia.

Increase

And how could the diversity *in*crease? Multiple mutations in a short timeframe?

Understatement

I don't really know anything about European mitochondrial DNA and I'm not entirely sure England (which was swept by various waves of invaders, not all of whom actually stayed, and then remained unchanged for a very long time) is a good example anyway. But I can say that over the last 100 years human genetic diversity (like linguistic diversity and cultural diversity) has plummeted, with truly distinct populations like the Andamanese (google them) and less-distinct but highly diverse populations like those of southern Siberia, Taiwan, and the Caucasus disappearing almost without comment.

Unfortunately, not only is it unfeasibly difficult to prevent such loss, it is also politically well-nigh impossible even to document it, as doing so involves admitting that a given population *is* distinct which is generally unacceptable to Russia and China in one way, and to politically-correct Western academics in another way. From peppercorn hair to multi-base counting systems, the vast majority of human biology, language and tradition has been lost, and a few selected strains and languages grow uncontrollably like some kind of bizarre algal bloom. Made of people.

This is not at all a recent phenomenon but in the last century it has massively speeded up. The catastrophic loss of ecological diversity may be just around the corner but the human equivalent has already happened and with a tiny fraction of the fanfare.

Re:Understatement

The catastrophic loss of ecological diversity may be just around the corner but the human equivalent has already happened and with a tiny fraction of the fanfare.

There have been many catastrophic losses of biodiversity on the planet and there will certainly be more before the Earth becomes barren.

I don't agree that the loss of societal habits, misconceptions and bugbears ("human culture") can be equated. These things may be dear to people but they are mostly rubbish.

Hmm

three out of every four individuals belonged to a different haplotype

I remember this game from Sesame Street. They showed 4 things - 3 were different and one was the same. Same as... uh..

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I remember this game from Sesame Street. They showed 4 things - 3 were different and one was the same. Same as... uh..

I have young kids, so I watch that show like 3 times a day. I am a Jedi freaking *master* at 'One of these things is not like the other'

Anno Domini

All right, if Slashdotters are going to continually jump all over misuse of "begs the question", then there's a pet peeve I'd like to add to that fervor. "300 AD", as it appears in the summary, is also incorrect usage. "AD" stands for anno domini, which is Latin for "in the year of the Lord". The phrase in Latin usage and traditional English usage comes properly before the number, not after. (Say it in full: "300 in the year of the Lord" sounds like an explanation of when something's tricentennial occurred. "In the year of the Lord 300" makes more sense as an absolute time reference.)

The convention of putting "AD" after the number is nothing but sloppy analogizing to "BC", which (being the English phrase "before Christ") does make more sense that way.

Note that the Royal Society writers did get it right. It's the Slashdot summary that's wrong.

Re:Anno Domini

IN A.D. 2101, WAR WAS BEGINNING

(lameness filter encountered. I suppose the mods will decide if it's accurate or not. Personally, I think this parenthetical bit ruins the joke. Lame.)

Endogamous marriages would preserve diversity

You know, if preserving genetic diversity and variation is really important, there is nothing like endogamous marriages. Marriages between parallel cousins. Marriage between the offspring of two brothers (or two sisters) would be called parallel cousin endogamous marriages. The cross cousin marriages (between offspring of a brother and his sister) is sometimes called endo but some dispute it and say it is exo. But is the genetic diversity brought about by such marriages worth it?

Huh

skewing the data in the local female population

So that's what they call it now.

Disparate time elements

I don't understand how the comparison can even be close to valid. The ancient group spans 700 years, the modern group is one snapshot. I dare say that any 700 year group would show more diversity than any single snapshot.

Parent's borderline racist argument is also silly

The parent makes several glaring mistakes in his reasoning.

Most importantly, it is the correct combination of genes that makes a successful organism as well as individual genes. 'Mixing' of groups of people is hugely advantageous for this reason.

Secondly, genes do not become lost when they combine with genes from another person to make a child. There is just a new combination of genes which can contribute to the whole genetic diversity of mankind. For example, we could take the idea that races should not interbreed a little further and say that people should not breed outside of their immediate family. The problem with this would be that genetic diversity could hardly ever increase, and by attrition mankind would be doomed. By separating races one creates several smaller separate gene-pools each of which is smaller than the original whole and hence more vulnerable.

Thirdly, by separating the societies it would become genetically/evolutionarily advantageous for one race to think of or treat the others as subhumans. By this argument I claim that you have implicitly invoked Godwin's law.

Also, I wish you luck procreating with your sister...

Two World Wars will do that for you.

When you send huge portions of your peak reproductive populaiton through the meat grinder in the span of about two generations, you can probably expect a decrease in genetic diversity. The good news about the next World War is that it will be nuclear and with all the radiation will come mutations which should help out with the genetic diversity issue.

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This is one of the fundamental hopes of evangelical religion

Fixed that for you.

I can't think of a single religion that doesn't want to see its beliefs embraced by the entire world. That's the point of religion--you believe you've found the truth and a

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Ok, I'm the AC that wrote the GP. I have to say... I agree with you in part. Depending on the theological views of various Christian groups, they might also have the same hope resulting in the same conclusions on how to bring the result about. I assume you