It is extremely hard to believe any state’s criminal justice justice system before the 20th Century (when police & justice systems started getting really effective) has ever had a significant genetic effect on its population. It is almost as hard to believe any modern justice system has had any such effect.
My own.
With a few exceptions that I acknowledge, like Russia, the longer a population has practiced urban civilization, the lower its murder rate is. The murder rate is a better way of evaluating the entire crime rate than the rate of reported crimes, because murders are more likely to come to the attention of the police.
Wow, this is absurd even by the standards of your usual arguments, given the obvious huge variations between populations in Euro-American civilization that are indistinguishable by that metric.
It must be true – after all, Iraq has the world’s lowest murder rate, right? Or is it Egypt? Syria? Well, it’s gotta be one of those Fertile Crescent countries…
Offhand, I can think of a factor sufficiently powerful, long lasting and near-universal to have caused relatively recent significant evolution. Disease. We’ve gone from being scattered hunter-gatherers to city dwellers in historical times, with an associated major increase in communicable disease and a very large death toll. Large portions of the population have died off and been replaced by the descendants of the more resistant. It’s just that all that evolution is going to be in the invisible immune system and biochemistry. And it’s not sexy enough for people who want claim “we are superiorrrrr!!!”
Gregory Cochran and Henry Harpending deal extensively with the effect diseases have had on human evolution. Europeans evolved a partial immunity to small pox and measles. African Negroes evolved a partial immunity to malaria. American Indians evolved neither. That is why Europeans were able to displace American Indians, and why they were not able to displace African Negroes.
Also, these partial immunities evolved within the past several thousand years, providing evidence that Stephen Jay Gould is mistaken in his assertion that nothing has happened of significance in human evolution during the past 40,000 or 50,000 years.
True, though that’s not the degree of short-term evolution that people like NDD are interested in making a case for, and not what Gould was (IIRC) arguing against.
No, that simply is not true. As BrainGlutton’s post explains at some length, “beneficial” is a relative term, applicable under some defined sets of circumstances but not under others. And while selective pressures may (or may not) favor conserving a mutation, other factors including random chance may eliminate it from a population regardless. Consider the hypothetical dung beetle who, by a miraculous mutation, achieves cognition and self-awareness. His marvelous gift though was not passed on because he was stepped on by an elephant or died in a savanna fire.
There is simply nothing about any random and rare “favorable mutation” that automatically increases its probabilistic fortunes.
The argument is about mutations that confer a selection advantage. Reading journal articles about population genetics is about like reading those on string theory. However, it takes very little of an advantage, just 3-5% more (children or chance of survival) per generation to spread it through a large population in a historically short amount of time, like 5000 years. (And some argue for faster spreads.)
I have no idea what NDD is trying to argue. And it’s true that science fiction mutations don’t work that way. Your hypothetical beetle is a science-fiction argument irrelevant to real-world mutations. I’m not sure what point you’re making either. It’s trivially true that most mutations are not beneficial and don’t spread. But we are the sum of those that were and did, so they can’t be written off easily.
Rather simplistic, is this not? I can think of a few additional factors, like total population size, rifles, socioeconomic factors involving the suitability and desirability of the land for agriculture by European style “family farms”, and of course distilled alcohol. Or are you suggesting that Europeans displaced Amerindians using malaria to which they also were susceptible?
And once again you conflate all Africans (“African Negroes”). Only certain African populations actually are resistant to malaria; you have been informed of this before. I am beginning to suspect that this conflation is more your point than not. Feel free to tell me that I am wrong.
Indeed, what it is suspicious about the book’s authors and the OP is not only the 10,000 year shout-out to creationists as Steve MB and **Latro **mentioned, but the quote of Gould that says that “We’re not just evolving slowly. For all practical purposes we’re not evolving.” is a favorite of creationists, they use it to distort what Gould said, he does not think that we are not evolving, by “practical” he is logically referring to what is taking place during a human lifetime. While Gould supports his Punctuated Equilibrium idea that evolution can remain static for eons and move relatively fast on occasion, that “fast occasion” also takes a very, very, long time.
http://www.mukto-mona.com/science/skybreak/scienceofevolution.pdf
(Big PDF file)
The point here is that Gould agrees with the evolutionary consensus, he is only pointing out one mechanism of evolution.
I don’t think you and I actually disagree. Obviously evolution has occurred, and we are the sum total of its operation. I am simply unable to accept blanket statements like “Beneficial mutations do not get diluted; they spread.” Perhaps I am a pedant, but strictly speaking, that statement is not true. Beneficial mutations may spread. But they may also be diluted to the point of irrelevance, especially in larger populations. Or they may be extinguished by random factors. And they are more likely to be extinguished than to be conserved.
Remember, a mutation occurs as a single event, in a single individual. Even if that mutation has some potential selective advantage, there will be no actual selective advantage unless circumstances provide a role for it in the life of the individual. For example, a gene for cold hardiness is unlikely to be “selected for” in a population that only experiences equatorial temperatures. Nor is a genuinely advantageous mutation immune to random accident. My beetle is exactly on point here, because even a highly advantageous mutation (brains!) can be eliminated by a random event outside of the mutation’s area of influence (fire wipes out all the beetles in the province, regardless of their brain power).
Once this precarious initial stage is overcome, as sometimes it will be, then a quite small selective advantage can indeed cause a mutation to be rapidly spread throughout a population. I do not dispute this fact, but I maintain that it only applies for a small subset of the total set of “beneficial mutations”.
I suspect that we’re just emphasizing different aspects of the same thing. It’s true that I may have a dozen beneficial mutations in my genes but unless I’m successful in passing them forward nobody will ever know if my mutations exist, let alone would be beneficial to the species.
My emphasis is on what happens once they do enter the larger gene pool. Both DNA analysis and sophisticated math show that gene spread can and does take place in significant percentages of the population in much less than 40,000 years.
I’m the farthest thing from a Creationist, but Gould died almost a decade ago and did his pioneering research a generation ago. He couldn’t be right - or wrong - about things he didn’t know about in his lifetime. The scientific consensus of today is what’s important. And this kind of narrowly defined accelerated evolution is the current consensus, AFAIK. I’m trying not to make broad statements about something I only know at the popular level, though. Yeah, that’s shocking.
I am uncomfortable that so many people are talking smack about a book they haven’t read. I am not launching an all-out defense of the book. But it flatly is not Creationism in any sense and is more nuanced than what some people here seem to believe.
Fair enough. I have not read the book, and am not in a position to judge.
As for your first paragraph, my slightly different emphasis would be that your “dozen beneficial mutations” will be passed on if you have children. And they may or may not be passed on if/when your children have children. And they will therefore have some (unknown) frequency in the total population. But the same can be said for any non-lethal but not-beneficial mutations you carry, as well as for all those other genes that are exactly the same as everybody else’s. You will have successfully passed them on by the simple expedient of having children. This though is not a product of evolution, merely of reproduction, since there was no selection either for or against those genes. In order for them to be “beneficial” or “not” there must be some set of circumstances that calls them into play, conferring either a benefaction or a detriment. If this does not happen, then random chance prevails.
But given an opportunity for selection, then extinction of a deleterious mutation or spread of a beneficial one can indeed be rapid.
“All things being equal” is weasel talk. In the real world, it’s smaller populations that have increased change from the norm - see “populations bottleneck” and “founder effect” for why this is the case. So the book’s based on a wrong premise right off the bat.
However, AFAIK the ideas of Gould would fit more with the idea of recent accelerated change. Incidentally, many creationists do believe in micro-evolution but reject Macroevolution (and the difference is BTW mostly in the imagination of creationists), and curiously most if not all of the evolution these researchers noticed seems to fit this view.
More problematic IMHO is that the maker of the book lost a lot of respect recently and the research mentioned by the OP on the Ashkenazi Jews has been used by defenders of scientific racism in the SDMB in recent threads.
http://scienceblogs.com/pharyngula/2009/04/crank_science_is_as_crank_scie.php
IMHO what we have here is a book that does deal with good science, but I have doubts on the conclusions when a lot of the science is still missing, or to be specific: I have doubts on what the OP is basing his conclusion that most researchers are supposed to be wrong with the science or that they continue to be mistaken because of political correctness.
This is bullshit. The lactose tolerance gene has cropped up more than once, in widely separated populations - easily shown by the fact that E-African lactase persistence is encoded in at least 3 different SNPs, all of which are different from the major European one. Lactose tolerance is something people have doubtless picked up time and again.
Yes, lactose tolerance is a common mutation and many groups since the advent of milking have undoubtedly benefited, as I said.
That’s not the same thing as saying that today’s spread of lactose tolerance comes equally from all sources. It’s the colonization of the rest of the world by Europeans that is unquestionably the source of much of the spread of lactose tolerance. And the northern European mutation can be traced back to the beginnings of milking in the Middle East, but that spread, along with farming and the Indo-European language, can be also traced east from the Mediterranean into at least India.
The many tribal peoples in Africa who can tolerate milk do seem to have multiple and separate evolutions. So? They’ve had limited effect on other populations.
The modern spread of genotypes is overwhelmingly the effect of 500 years of European colonization. That scrambled everything.
I do not believe this is true. Evolution works more quickly in small, isolated populations.