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."

I Can Vouch For That!

[morari (1080535)]

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

skewing data

[PhrostyMcByte (589271)]

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.

Some points

[wandm (969392)]

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]

The historic sample is kinda small

[bomanbot (980297)]

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.

[Reeses (5069)]

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

[NetDanzr (619387)]

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

[NJVil (154697)]

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!"

All the scientific research aside...

[goldspider (445116)]

...I blame West Virginia.

Increase

[ardor (673957)]

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

Understatement

[kahei (466208)]

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

[Dystopian Rebel (714995)]

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

[JMZero (449047)]

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..

Re:Is this news?

[krgallagher (743575)]

"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?

[j00r0m4nc3r (959816)]

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

Re: Is this news?

[Black Parrot (19622)]

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

Sounds like something a Canadian would say.

Re:Is this news?

[kahei (466208)]

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?

[mwvdlee (775178)]

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.

Re:Is this news?

[Sciros (986030)]

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?

[TheEmptySet (1060334)]

"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?

[geoffspear (692508)]

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.

Re:

[DarenN (411219)]

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 in a greater pool of individuals.

Not entirely relevant to the article, though.

Re:Don't worry

[hedwards (940851)]

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.

Parent's borderline racist argument is also silly

[TheEmptySet (1060334)]

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...

Re:Anno Domini

[FiloEleven (602040)]

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.)

Two World Wars will do that for you.

[alcmaeon (684971)]

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.