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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."
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 by as many different men as possible throughout their lifetimes.
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.
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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.
Whence? Hence. Whither? Thither.
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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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.
The catch, of course, is that "fittest" depends on the environment that the organism lives in. And "less suitable genetic traits" are just the ones that happen to result in the individual's untimely death (i.e., before it reproduces). My myopia is obviously a less suitable genetic trait that could get me killed if I get into a situation where I need to see a danger at a distance. But none of my nearly-blind ancestors managed to get themselves killed before I came along, and I have managed to reproduce, and so this bad trait has been propagated to another generation. There seem to be certain diseases that are like that as well. Some inherited traits just happen to help a genetic line survive, and some of them just happen to not to have caused it to be extinguished.
I remember an article a few years ago that essentially said that the current generation of people is composed of a very small sample of the people who lived in the Middle Ages (to pick an epoch). Most of the family lines of that earlier epoch have been extinguished, for whatever reason. So in essence, we are whittling down to some few genetic lines that will have been lucky enough to make it that far. Whatever it is, it won't be perfect.
I think this is news because it is confirmation of an old idea that is still hotly debated.
"Who controls the past controls the future. Who controls the present controls the past." -- George Orwell
This has been happening ever since mankind outlawed rape.
At the bottom of the
Has anyone ever done a study on what is probably the most inbred population on the planet - the European royals?
I assume you are referring to the US public schooling system. In which case you are quite right and it worries me to see that in the US children are increasingly taught that scientific reasoning must depend on such assumptions. This turns the whole debate away from what it should be. This is why, when I have visited the US I have never dared wear my "Just Say No To Evolution" T-shirt for fear that people might think it anything other than a cynical joke about this debate. Over here in Britain we are only just beginning to feel the effects of the Christian Nonsense Lobby in our state schools and it has yet to provoke the sort of outrage that leads people to publicly make idiotic arguments against it for lack of understanding of the perfectly good ones.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
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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Prov 9:8 Do not rebuke mockers or they will hate you; rebuke the wise and they will love you.
Well, to start with, you're mixing up the genotype and the phenotype. But I'd rather not get into any more detail since my explanations are nowhere near as accurate, clear, or concise as the "layman's guides" available...I highly recommend Ernst Mayr's or Stephen Jay Gould's work and will leave it at that.
Geeks like to think that they can ignore politics, you can leave politics alone, but politics won't leave you alone.-rms