Extinctions weirdness

| 45 Comments

When a paper gets press, the authors get some weird reactions. With the extinctions paper, one guy emailed us to say that he agreed that species extinctions were a big problem, and that humans were the cause. However, he said, we had the details of the cause was wrong. The real cause was contrails.

That, though, was not nearly as weird as this: “Congrats Nick Matzke for Publishing ID Sympathetic Paper in Nature!” by Sal Cordova.

Can anyone explain the psychology here? I’m normally pretty good at psyching out creationists, but this one leaves me mystified.

45 Comments

My guess would be that any paper with a title of the form evolution-related-thing followed by “weirdness” is automatically a problem for evolution, and therefore a proof of ID in the minds of the ID-folks.

It’s Sal’s way of saying he’s not as bright as he thinks he is. But we already knew that.

Sal is the poster boy for the Dunning-Kruger Effect.

He spelled it out pretty plainly:
-That’s right, if the rate of extinction exceeds the rate of speciation, then obviously speciation through natural selection does not happen at all!
-Also, if humans are the cause, that just shows that nature doesn’t automatically replace the diversity that’s lost like you Darwinists always assume it should!
-If nature needs intelligent intervention to stop the intelligently-caused extinctions, well that just shows that intelligence is needed in the system!

How can one argue with this unassailable logic and impenetrable wall of understanding? One can’t. One can’t argue with it. To argue with it is pointless and futile, you may as well wave the white flag now. Sal’s got your number.

I should just learn never to click through on links to UD. That’s one giant heap of burning stupid Sal’s responsible for there.

I think his argument is summarized here:

Salvador Cordova reacting to Nick’s extinction paper:

One might argue humans are the cause of current extinction rates. Even granting that is true, it only goes to show nature is under no obligation to conform to the Darwinist view that nature inevitably generates more novelty than it destroys!

He thinks “Darwinism” made a prediction that nature will always generate more novelty than it destroys. [Permian extinction? K-T Boundary? All the other mass extinctions at the end of geologic periods? Those overoptimistic Darwinists must not have noticed them!]

This follows a pattern of creationist objections: find a case where biologists might have thought that X would happen. But then they find out that Y happened instead, and point this out. Obviously, say the creationists, a “prediction of Darwinism” has been falsified. A prediction of Darwinism is any prediction made by a “Darwinist”, i.e. by anyone who isn’t a creationist.

So Sal Cordova is a liar. That’s not even news; He’s been lying since at least when he made a crude joke regarding P Z Myers’ daughter Skatje, accusing her of practicing beastiality.

http://scienceblogs.com/pharyngula/[…]limy_sal.php

So as a layman what I understand as one (of the many) driving forces behind evolution is that organisms evolve to fill gaps, (not conciously of course but by simply falling in them (adapting to take advantage of a new food supply for example).…..and sal cordoba seems to be missing the fact that mass extiction events take away those opportunities. (Example no wolves left in NYC), yet no other big carnivore has moved in because there is no gap to be filled mainly because the same threat that killed off the wolves is still alive and kicking (humans) and would do exactly the same with say, pumas.……the big irony that scapes him (I think) is the fact that if evoution had a driving intelligence (if nature was an intelligent designer); then it would have gotten rid of the humans to make space to continue with its business. It is very difficult to grasp the concept of mechanisms existing as a set of rules yet having no purpose or serving any goals. (High school biology may not be enough to grasp Sal’s point of view please feel free to let me know. If I missed the bus here).

The comments are interesting. There is much about John Sanford’s book, “Genetic Entropy,” which apparently argues that the accumulation of ‘slightly detrimental mutations’ which, in turn, apparently “dooms any theory of common ancestry, or at least any such theory that denies the hand of an intelligent agent stepping in and cleaning up the genomes from time to time” … the old 2nd LoT argument in sheep’s clothing.

Sal himself quotes Gould and Raup on gradualism (a major non sequitur) and “opines” that “[t]he fact of mass extinction does not given (sic) any support whatsoever that Darwinian mechanismS actually work in the way Darwin suggests. The mechanism of diversification may still be somewhat unknown” … as if Darwin was the last word on evolutionary theory and ignoring the fact that Gould and Raup are among the many scientists who have advanced evolutionary theory since Darwin.

Sal also says:

If Darwinists argue the fittest survive, isn’t it a good thing the unfit are dying via mass extinction? IS Nick is (sic) suggesting we arrest the good work NS is doing to eliminate inferior species?

Darwinists say one thing and then act like creationists when trying to save “inferior” species.

Apparently he can’t understand that mass extinctions caused by humans can affect humans’ fitness and tip us over into the category of “inferior” species.

Basically, Sal is into the ol’ “if anything shows that Darwin was wrong or incomplete on any point, evolutionary theory is wrong” game.

But one commenter neatly turns around Sal’s sneer at “Darwinists”:

Ken Miller objects to ID because it means that God is allowing many species to go extinct and then to replace them with almost identical species.

Not only a serial creator, but an INCOMPETENT serial creator. Have any of you ID proponents ever thought of the theological implications of your ‘theory’?

John Pieret said: … the old 2nd LoT argument in sheep’s clothing.

“Everything spontaneously goes to hell if an intelligence doesn’t magically keep it running at all times.”

OK, this is off-topic and it won’t hurt my feelings if you delete the post or whatever, but I am wondering if you guys are aware that the DI is about to succeed in Tennessee: http://blogs.knoxnews.com/humphrey/[…]bill-or.html

Sanford’s book is a joke.

mario said:

So as a layman what I understand as one (of the many) driving forces behind evolution is that organisms evolve to fill gaps, (not conciously of course but by simply falling in them (adapting to take advantage of a new food supply for example).

Osmotic pressure. :-)

Well maybe someone should congratulate Dembski on publishing something that supports evolutionary theory. His “equations” clearly show that the designer doesn’t have to be intelligent. Anything at all that increases information, such as for example random mutations and natural selection, could be the designer. So Dembski has proven that Darwin was right!

Look, creationists don’t have to make any sense at all. They know they are right and god is on their side, so all evidence MUST be evidence for creationism, no matter how illogical or self contradictory their position might be.

Now Sal, all you have to do is show where the bible talks about SIX mass extinctions in the last 6,000 years and demonstrate the devine mechanism whereby all of this diversity and more was replaced six times in the last 6,000 years and maybe someone will take you seriously. Until then you are just another schizophrenic wannabe with delusions of rationality.

Maybe some day Sal will realize that evolution has absolutely no reason to preserve the human species. Maybe then he will realize the mistake he has made in denying the reality of evolutionary and the knowledge that could be used to try to save humanity. Then again, I guess just sittin around and prayin is easier than actually understanding anything.

That article was painful to read. It’s telling, though: he seems to think that Darwinism means that nature has an “obligation” to “generate more novelty than it destroys”, and that therefore mass extinctions somehow refute Darwinism. He makes that claim again in the comment that John Pieret referred to:

… mass extinction on the whole is not favorable to the Darwinian view that nature is friendly to making new species to replace the old ones via Darwinian processes.

Of course, no naturalist would ever expect there to be such an obligation, or that nature is “friendly” in any meaningful sense.

The only thing we can say, is that since there is life now, nature has apparently not yet succeeded at making all of it go extinct. Cordova, on the other hand, seems to be projecting his own conviction that the arrival of man was pre-ordained, or inevitable, onto evolutionists.

mrg said:

John Pieret said: … the old 2nd LoT argument in sheep’s clothing.

“Everything spontaneously goes to hell if an intelligence doesn’t magically keep it running at all times.”

Man, if it were me I would have designed a Universe that involved much less upkeep.

Wheels said: Man, if it were me I would have designed a Universe that involved much less upkeep.

Does seem a bit laborious, doesn’t it?

Am glad that there were two sensible people posting over at UD, leenibus and bachfiend, critiquing Sal Cordova’s latest example of breathtaking inanity (I guess the anti-ID filter wasn’t working well at UD.). Of course, in his risible replies Sal ignored important aspects of paleobiology, ecology and conservation biology. Not only did he ignore, but he missed completely, these noteworthy, quite appropriate, observations by leenibus:

“Are you remotely familiar with evidence for mass extinctions during Earth’s geologic past? The expansion and development of many new species takes place AFTER the lethal conditions causing the mass extinction are finished, not during the event. Organisms are not madly producing new replacement species during the time that it takes for a meteor to explode, or during massive eruptions of flood basalts. As long as humans continue to wipe out species by killing them directly or by destroying their environment, the extinction is still going on. Hopefully we will eventually begin acting intelligently enough to halt the destruction.”

If nothing else, Sal’s latest post demonstrates that he is suffering from some virulent kind of delusionaly psychosis as well as an acute case of poor reading comprehension (Of the kind we see all too often from FL, ID and IBIG.).

John Pieret said:

Basically, Sal is into the ol’ “if anything shows that Darwin was wrong or incomplete on any point, evolutionary theory is wrong” game.

But one commenter neatly turns around Sal’s sneer at “Darwinists”:

Ken Miller objects to ID because it means that God is allowing many species to go extinct and then to replace them with almost identical species.

Not only a serial creator, but an INCOMPETENT serial creator. Have any of you ID proponents ever thought of the theological implications of your ‘theory’?

That commenter you cite was bachfiend. I thought it was a riot that in response, this IDiot barfed:

“We don’t care about theological implications. And I also doubt Ken Miller is a practicing catholic. The way he lies ndmisrepresents ID he needs to go to confession on a daily basis.”

How ironic, that’s been my advice for Mikey Behe, Bill Dembski, Casey Luskin and the rest of their pathetic fellow band of Dishonesty Institute mendacious intellectual pornographers for years; THAT THEY NEED TO CONFESS TO THE ALMIGHTY for being the sleazy pimps that they are for Intelligent Design cretinism.

I would have to characterize this as both dishonest and suggestive of severe mental or cognitive problems.

If Darwinists argue the fittest survive, isn’t it a good thing the unfit are dying via mass extinction? IS Nick is (sic) suggesting we arrest the good work NS is doing to eliminate inferior species?

Darwinists say one thing and then act like creationists when trying to save “inferior” species.

1. Use of the terminology “Darwinist” and “survival of the fittest” is anachronistic.

2. The theory of evolution is a neutral scientific theory, not a system of ethics or aesthetic judgments.

3. Virtually no science supporter holds to a system of ethics or subjective judgments, independent of the theory of evolution, that views mass extinctions as inherently “good” or passes emotional judgment on extinct lineages.

4. “Is Nick saying we arrest the good work…” is self-contradictory. If Nick is identified as a “Darwinist”, and Nick advocates efforts to reduce human-caused extinctions, then the prior claim that “Darwinism” favors extinctions must be false, even by the isolated internal logic of Cordova’s own writings.

5. “Darwinists”, if that term is accepted as a synonym for people who accept the major theory in mainstream biomedical science, have never “said” that any particular type of extinction was a “good”* thing (*with the possible exception of the extinction of smallpox virus in the wild).

6. Working to reduce extinctions is not “behaving like a creationist”. Creationists as a group do not have a strong track record as environmentalists (although some individual creationists may).

There is no possible rationale for writing something this laden with blatant falsehoods and internal logical inconsistencies.

harold said:

I would have to characterize this as both dishonest and suggestive of severe mental or cognitive problems.

If Darwinists argue the fittest survive, isn’t it a good thing the unfit are dying via mass extinction? IS Nick is (sic) suggesting we arrest the good work NS is doing to eliminate inferior species?

Darwinists say one thing and then act like creationists when trying to save “inferior” species.

1. Use of the terminology “Darwinist” and “survival of the fittest” is anachronistic.

2. The theory of evolution is a neutral scientific theory, not a system of ethics or aesthetic judgments.

3. Virtually no science supporter holds to a system of ethics or subjective judgments, independent of the theory of evolution, that views mass extinctions as inherently “good” or passes emotional judgment on extinct lineages.

4. “Is Nick saying we arrest the good work…” is self-contradictory. If Nick is identified as a “Darwinist”, and Nick advocates efforts to reduce human-caused extinctions, then the prior claim that “Darwinism” favors extinctions must be false, even by the isolated internal logic of Cordova’s own writings.

5. “Darwinists”, if that term is accepted as a synonym for people who accept the major theory in mainstream biomedical science, have never “said” that any particular type of extinction was a “good”* thing (*with the possible exception of the extinction of smallpox virus in the wild).

6. Working to reduce extinctions is not “behaving like a creationist”. Creationists as a group do not have a strong track record as environmentalists (although some individual creationists may).

There is no possible rationale for writing something this laden with blatant falsehoods and internal logical inconsistencies.

Thanks for stating the obvious harold, but I felt it was unnecessary to cite each and every one of Sal’s delusional remarks. However, I suppose someone had to do it, and am glad it was you.

Joe Felsenstein said: Obviously, say the creationists, a “prediction of Darwinism” has been falsified.

“…thereby proving intelligent design creationism is true!”

Creationist ignorance is so tiresome - but we’ve got to keep pointing out that their scientific illiteracy is just that: ignorance.

Paul Burnett said:

Joe Felsenstein said: Obviously, say the creationists, a “prediction of Darwinism” has been falsified.

“…thereby proving intelligent design creationism is true!”

Creationist ignorance is so tiresome - but we’ve got to keep pointing out that their scientific illiteracy is just that: ignorance.

But ignorance that is deeply rooted in delusional, quite disturbed, individuals like Sal Cordova.

Sal of Several Shallow Degrees Wrote:

Nick Matzke unwittingly gives more evidence for the claims of ID proponent John Sanford.

It is not surprising that Sal would refer to Sanford’s “genetic entropy.”

But it does make me suspect that ID/creationists – and Sanford in particular – don’t grasp that nature of delicate organisms that have evolved on top of somewhat more robust templates that have endured even harsher environments and nevertheless became extinct.

Mild conditions can allow more complex and more delicate organisms to evolve. But when the environmental conditions move outside that window of “comfort,” extinctions are going to occur; even if those environmental conditions were changed by some of the creatures that existed within it. We’ve seen it before.

Thanks for stating the obvious harold, but I felt it was unnecessary to cite each and every one of Sal’s delusional remarks. However, I suppose someone had to do it, and am glad it was you.

I think it is valuable.

What Cordova is doing here, albeit in a clumsy and over-the-top way, is actually a common abuse of the theory of evolution.

It is often claimed that the theory of evolution obliges some particular ethical or social system.

Sometimes this is done by advocates of an ethical or social system, who accept the theory of evolution but falsely tie it to their ideology. People who do this may understand evolution correctly, although they usually have an oversimplified view of it.

Other times, as here, the false claim is made that the theory of evolution obliges some kind of ethical system, that the ethical system is unacceptable, and that therefor the theory of evolution must be false. Here, the false claim that the theory of evolution is an ethical system is compounded by the flawed logic that something can be judged to be untrue if one does not like it.

The real cause was contrails.

Never heard of “chemtrails” before? And then, of course, there’s HAARP mind control ionospheric research facility.

Suddenly I wonder why the Arecibo dish isn’t is the same category – I’ll have to look that up. On looking over details of the Microsoft Kinect gesture-recognition system for the XBox 360, I got to wondering if people were claiming it was a spy device, but on checking nobody’s tried to claim that so far except as a joke.

Creationists aren’t the only crazy people on the planet, and in fact it’s arguable that they’re the craziest.

I want to comment on something Sal wrote, not because it has any significance in relation to the paper, but because it incidentally raises an important point. Sal wrote: “If Darwinists argue the fittest survive, isn’t it a good thing the unfit are dying via mass extinction?” The implication is that all mortality contributes to natural selection. But that is pretty clearly false. What matters is that the cause of the mortality is such that the phenotypes resulting from different genes have a different probability of avoiding or withstanding it. There is no gene that confers immunity from falling asteroids or, more prosaically, on many of types of accidents. It is even more obvious that events that wipe out whole populations or whole taxa leave no possibility of further adaptation in those whole populations and taxa.

This line of thought reminds me of a question of my own I’ve never seen addressed. People commonly worry that medical interventions or even just the general ease and safety of civilized life will thwart natural selection and lead to a debasement of the species. Has anybody investigated whether the reverse is true? If living in civilization means that you’re much less likely to die from some random, previously unavoidable accident, doesn’t that imply that a greater proportion of differential mortality will reflect evolutionarily meaningful mortality? Doesn’t the signal come through better if there is less static?

Sal Cordova writes as though he were the bastard child of Michael Egnor and Sarah Palin.

harold said:

6. Working to reduce extinctions is not “behaving like a creationist”. Creationists as a group do not have a strong track record as environmentalists (although some individual creationists may).

Indeed, and here’s a great example of some of the current pro-active anti-environment propoganda that’s being published.

Religious Right on Dangers of Environmentalism

Oh, if I could only buy Sal for what he’s worth – and sell him for what he thinks he’s worth.

Dishonesty Institute mendacious intellectual pornographer Casey Luskin has succumbed to the same kind of idiocy again, which John Farrell notes eloquently here:

http://blogs.forbes.com/johnfarrell[…]cience-test/

This line of thought reminds me of a question of my own I’ve never seen addressed. People commonly worry that medical interventions or even just the general ease and safety of civilized life will thwart natural selection and lead to a debasement of the species. Has anybody investigated whether the reverse is true? If living in civilization means that you’re much less likely to die from some random, previously unavoidable accident, doesn’t that imply that a greater proportion of differential mortality will reflect evolutionarily meaningful mortality? Doesn’t the signal come through better if there is less static?

This is actually a meaningful question. Here are some partial replies. Let me state in advance that I strongly support access to health care and public health for all human beings, that I support the right of all human beings who possess the basic competence to raise children to have as many children as they want to and can, and that there is no current evidence that fifty years or so of more-effective-than-historical-norm medicine has had any direct genetic impact on humanity. It may have resulted in relatively slower population growth in the areas where it is available, as there is a very, very strong relationship between childhood mortality and family size; people who know that each child is at a high risk of dying tend to have more children, and although this can be and often is overwhelmed by very high childhood mortality, it often results in greater net population growth despite higher childhood mortality. (Thus, the related question, “does giving medical care to poor children cause long term overpopulation”, is best answered “most likely the opposite” on the grounds of currently available data.)

Moving on…

For the most part, current medical interventions deal with diseases that are either related to environmental events that can hit anybody in a fairly random or slightly biased but near random pattern (infectious disease, trauma), and or impact mainly after reproductive years, or, in many cases, both.

Furthermore, even in cases where purely Mendelian diseases have become treatable, e.g. phenylketonuria http://en.wikipedia.org/wiki/Phenylketonuria, the basic mathematics of Mendelian inheritance remind us that, when heterozygotes are not selected against, the allele is more or less fixed in the population anyway (from the perspective of human time scales). Survival of these very rare homozygotes impacts very trivially on the genetics of the overall population.

Furthermore, many of the ailments of civilization that might seem to be negative for survival in a simpler society, such as myopia, asthma, allergies, and so on, have genetic correlates but tend not to be expressed except in relatively modern environments; myopia is associated with ethnicity but is always rare to non-existent in pre-literate populations and always common in literate populations, and also associated with amount of childhood reading, for example. In fact, in theory, a genetic propensity to myopia can be selected againt in a literate population, where it is expressed, but not in a pre-literate population, where the genetic tendency is silent.

It is true that many modern humans are largely descended from populations that were under severe selective pressure for resistance to infectious disease, e.g. Western Europe, for centuries. But the mechanisms of resistance we have inherited tend to be many, and redundant, and are not selected against, so one would not expect significant loss of them over a human-meaningful time scale.

So the answer is “no”, at least for now. Other than the fact that populations with low childhood mortality tend to grow more slowly than most population with high childhood mortality, there is not much reason to think that modern medicine has much of a “selection” impact.

harold said:

This line of thought reminds me of a question of my own I’ve never seen addressed. People commonly worry that medical interventions or even just the general ease and safety of civilized life will thwart natural selection and lead to a debasement of the species. Has anybody investigated whether the reverse is true? If living in civilization means that you’re much less likely to die from some random, previously unavoidable accident, doesn’t that imply that a greater proportion of differential mortality will reflect evolutionarily meaningful mortality? Doesn’t the signal come through better if there is less static?

This is actually a meaningful question. Here are some partial replies. Let me state in advance that I strongly support access to health care and public health for all human beings, that I support the right of all human beings who possess the basic competence to raise children to have as many children as they want to and can, and that there is no current evidence that fifty years or so of more-effective-than-historical-norm medicine has had any direct genetic impact on humanity. It may have resulted in relatively slower population growth in the areas where it is available, as there is a very, very strong relationship between childhood mortality and family size; people who know that each child is at a high risk of dying tend to have more children, and although this can be and often is overwhelmed by very high childhood mortality, it often results in greater net population growth despite higher childhood mortality. (Thus, the related question, “does giving medical care to poor children cause long term overpopulation”, is best answered “most likely the opposite” on the grounds of currently available data.)

Moving on…

For the most part, current medical interventions deal with diseases that are either related to environmental events that can hit anybody in a fairly random or slightly biased but near random pattern (infectious disease, trauma), and or impact mainly after reproductive years, or, in many cases, both.

Furthermore, even in cases where purely Mendelian diseases have become treatable, e.g. phenylketonuria http://en.wikipedia.org/wiki/Phenylketonuria, the basic mathematics of Mendelian inheritance remind us that, when heterozygotes are not selected against, the allele is more or less fixed in the population anyway (from the perspective of human time scales). Survival of these very rare homozygotes impacts very trivially on the genetics of the overall population.

Furthermore, many of the ailments of civilization that might seem to be negative for survival in a simpler society, such as myopia, asthma, allergies, and so on, have genetic correlates but tend not to be expressed except in relatively modern environments; myopia is associated with ethnicity but is always rare to non-existent in pre-literate populations and always common in literate populations, and also associated with amount of childhood reading, for example. In fact, in theory, a genetic propensity to myopia can be selected againt in a literate population, where it is expressed, but not in a pre-literate population, where the genetic tendency is silent.

It is true that many modern humans are largely descended from populations that were under severe selective pressure for resistance to infectious disease, e.g. Western Europe, for centuries. But the mechanisms of resistance we have inherited tend to be many, and redundant, and are not selected against, so one would not expect significant loss of them over a human-meaningful time scale.

So the answer is “no”, at least for now. Other than the fact that populations with low childhood mortality tend to grow more slowly than most population with high childhood mortality, there is not much reason to think that modern medicine has much of a “selection” impact.

I’m not absolutely sure you got my point. I am suggesting that modern medicine and, perhaps more importantly, the relative peacefulness of modern societies, may have a positive impact on the rate of evolution. People construct a niche for themselves (to use a term from the biologist Odling-Smee) that changes what gets selected for. For example, in societies with politics genes that tend to increase eloquence may be selected for. My question is whether the decline in meaningless, random death, another feature of our niche, might also alter the selective landscape and make it more likely that positive adaptations would increase faster since fewer of the bearers of these genes would die unavoidably.

Just checking.

Nick, curiously, why would you feel the need to suggest Man needs to stem the tide of extinctions? Its a part of nature. Let it happen.

The human population is 7b, projected to hit 12b by 2050. Should we urgently implement population controls in China, India, Indonesia, etc? One species over-population will surely be corrected by evolution.

So, relax. Let it all happen. After all, it’s evolution in action.

steve p. babbled:

Nick, curiously, why would you feel the need to suggest Man needs to stem the tide of extinctions? Its a part of nature. Let it happen.

Evolutionary Biology is descriptive, not prescriptive, moron.

A world where children ask “What’s a frog?” or “What’s a tiger?” is, in my opinion, a crappy world. Not that you would care, given as how you’ve never seen a live animal in your entire life.

The human population is 7b, projected to hit 12b by 2050. Should we urgently implement population controls in China, India, Indonesia, etc? One species over-population will surely be corrected by evolution.

So, relax. Let it all happen. After all, it’s evolution in action.

This is exactly why I regard creationists, like you, Steve P, as being human monsters: they are willfully stupid, and spew slander while hypocritically priding themselves on being incapable of empathizing with other humans.

And yet, you piss and moan bloody murder when we point out that you want us to respect your opinions on subjects you know absolutely nothing about.

I’m not absolutely sure you got my point. I am suggesting that modern medicine and, perhaps more importantly, the relative peacefulness of modern societies, may have a positive impact on the rate of evolution. People construct a niche for themselves (to use a term from the biologist Odling-Smee) that changes what gets selected for. For example, in societies with politics genes that tend to increase eloquence may be selected for. My question is whether the decline in meaningless, random death, another feature of our niche, might also alter the selective landscape and make it more likely that positive adaptations would increase faster since fewer of the bearers of these genes would die unavoidably.

Just checking.

I got your point and addressed it logically.

I apologize. The fault is mine. I assumed substantial knowledge of the underlying mechanisms of biological evolution.

I explained why there is no reason to think that modern medicine, in isolation, is impacting in a significant way on the frequency of alleles in the populations it serves. I didn’t use the word “allele”, but used other terms which are more or less synonymous, and went into a bit of detail as to why it probably is not.

Biological evolution can be tersely described as “a change in the frequency of alleles in a population”. Alleles are created by mutations, and their frequency in a population is impacted by natural selection, random genetic drift, and arguably some other processes. The underlying mutation rate in human reproduction is not being greatly impacted by modern medicine, and random genetic drift by definition would not be, and tends to have limited effects in large populations at any rate. Therefore the only serious way modern medicine could impact on human evolution is by selecting for or against specific alleles, in a way that impacts on their frequency in the population at a reasonable time scale. I argued that it is probably not currently doing so to any significant degree.

I cannot know this for certain, but it is my educated conjecture. If you still don’t follow the reasoning here, do some reading and come back with some specific questions. I can’t guarantee much time here, but I try to check in and will be happy to answer specific questions.

harold said:

I’m not absolutely sure you got my point. I am suggesting that modern medicine and, perhaps more importantly, the relative peacefulness of modern societies, may have a positive impact on the rate of evolution. People construct a niche for themselves (to use a term from the biologist Odling-Smee) that changes what gets selected for. For example, in societies with politics genes that tend to increase eloquence may be selected for. My question is whether the decline in meaningless, random death, another feature of our niche, might also alter the selective landscape and make it more likely that positive adaptations would increase faster since fewer of the bearers of these genes would die unavoidably.

Just checking.

I got your point and addressed it logically.

I apologize. The fault is mine. I assumed substantial knowledge of the underlying mechanisms of biological evolution.

I explained why there is no reason to think that modern medicine, in isolation, is impacting in a significant way on the frequency of alleles in the populations it serves. I didn’t use the word “allele”, but used other terms which are more or less synonymous, and went into a bit of detail as to why it probably is not.

Biological evolution can be tersely described as “a change in the frequency of alleles in a population”. Alleles are created by mutations, and their frequency in a population is impacted by natural selection, random genetic drift, and arguably some other processes. The underlying mutation rate in human reproduction is not being greatly impacted by modern medicine, and random genetic drift by definition would not be, and tends to have limited effects in large populations at any rate. Therefore the only serious way modern medicine could impact on human evolution is by selecting for or against specific alleles, in a way that impacts on their frequency in the population at a reasonable time scale. I argued that it is probably not currently doing so to any significant degree.

I cannot know this for certain, but it is my educated conjecture. If you still don’t follow the reasoning here, do some reading and come back with some specific questions. I can’t guarantee much time here, but I try to check in and will be happy to answer specific questions.

IMHO you got it right harold. What Jim Harrison has suggested is mere wishful thinking on his part. Moreover, it is only lately that medicine is starting to think seriously about evolutionary biology and how it impacts on human health (As an aside, I still chuckle recalling a lecture given more than a decade ago by a prominent British epidemiologist at a noted epidemiological department of a prominent private university that shall remain nameless, in which the first picture shown on that lecture was that of a certain well known mid 19th Century British gentleman in his thirties, and that figure was introduced by the speaker as the father of epidemiology (Yours truly was the only one who knew immediately who that figure was and mine was the only hand raised.).).

steve p. the ignorant delusional Taiwanese-based rug merchant barfed:

Nick, curiously, why would you feel the need to suggest Man needs to stem the tide of extinctions? Its a part of nature. Let it happen.

The human population is 7b, projected to hit 12b by 2050. Should we urgently implement population controls in China, India, Indonesia, etc? One species over-population will surely be corrected by evolution.

So, relax. Let it all happen. After all, it’s evolution in action.

Your latest risible example of breathtaking inanity ignores that fact that we, humanity, could act to ensure that the current unusually high rates of extinction are reduced to nil. It also ignores the fact - which Nick and his colleagues demonstrated quite persuasively - that these current rates are as high as those we have seen for great mass exinctions like those at the end of the Cretaceous and toward the end of the Permian.

My question is whether the decline in meaningless, random death, another feature of our niche, might also alter the selective landscape and make it more likely that positive adaptations would increase faster since fewer of the bearers of these genes would die unavoidably.

I think I should provide a more in depth answer to this part.

In general, causes of death that are more or less random would be independently distributed with regard to positive adaptations. So modern medicine would equally benefit both those with the adaptation and those without the adaptation, and the frequency of the underlying alleles would not change - there would just be a lot more people, across a different age distribution, with all allele combinations.

On a more romantic note, if there were some type of allele combination that concurred great musical talent or something, but was also associated with great sensitivity to bacterial infection, such people would be more likely to thrive in a sanitary, antibiotics-available environment. But if it were a rare allele combination to begin with, it might take centuries or longer for the frequency increase to be perceptible.

Also, I should add, I’m giving a pragmatic answer. One can imagine any number of theoretical scenarios under which modern medicine would impact on human evolution. For example, if there were some type of homozygous state that created both high risk of death from common bacterial infections, but marked increase in fertility, and if the people who had that allele combination chose to make full use of their fertility, such an allele combination might blast up in frequency in a population with sanitation and antibiotics, and plunge down in frequency if those environmental factors were removed.

So what I’m saying is that, purely from a pragmatic perspective, I don’t think there’s much evidence of anything like that happening. We have the odd situation of having changed out environment a great deal without corresponding strong change in allele frequencies. However, this strange situation is probably somewhat characteristic of humans, due to the facts that 1) humans as a species don’t have terribly much genetic variability and 2) the “average” human phenotype is highly adaptable to a wide variety of environments, even with simple technology.

It sounds like Jim Harrison’s clarification posits something like the scenario from The Time Machine: humans creating their own niches, thus having speciation events occurring along the lines of similar interests/socioeconomic status/what have you. Is this it?

Harold, I’m quite aware of the mechanisms of evolution. Nothing in your brief explanation of biological evolution is news to me: I’ve given exactly the same explanation to other people many times. What I was talking about would be at most a wrinkle on top of the standard account you read about in population genetics textbooks like Crow and Kimura. I may be making an error on the order of somebody who doesn’t get Hardy-Weinberg and thinks blue eyes will die out because the gene is recessive, but I don’t think your response addressed my idea at all, which is not to say it deserves addressing.

In a population with less random death, more individuals with a favorable mutation survive but so do more individuals who lack the mutation. I understand that. What makes me wonder if something else is going on, something that is hidden by the usual way of calculating selection coefficients, is that if you think of the environment as sending messages to the genome, you’d think that editing the messages to remove some of the random ones would increase the chances that the meaningful messages would get through. By the way, I’m aware that intuition isn’t evidence, though it is where hypotheses commonly come from.

I started wondering about all this after reading the umpteenth bit about how medicine is going to lead to genetic degradation; but medicine has very little to do with the case. After all, it’s an open question if doctors increased or decreased mortality over the existence of the human species. To my way of thinking the more significant niche effects involve the greater security for children from starvation, accidents, and violence that goes along with better organized societies. That non-genetic inheritance (culture, broadly speaking) alters selection patterns is widely accepted these days—pretty obviously, for example, the existence of languages makes it more valuable to be intelligent even though gray matter is energetically expensive. It has been plausibly argued, in fact, that there was a crucial positive feedback between innovations and genetic change that partly explains the rapid growth of brain size in our lineage. My suspicion that there might also be another, probably smaller effect resulting from a culture-based lessening of random mortality would just be a footnote to this sort of explanation.

Jim Harrison -

I find the points you are bringing up interesting.

What makes me wonder if something else is going on, something that is hidden by the usual way of calculating selection coefficients, is that if you think of the environment as sending messages to the genome,

What would be the mechanism by which the environment sends messages to the genome? What is the physical nature of these messages? How does the genome respond to them?

(Under the theory of evolution, when DNA is replicated, the offspring strands differ from the template strands in sequence, because of well-understood biochemical events called mutations. Mutations may impact on the phenotype of offspring, or not. Phenotypes may be selected for or against in a given environment. However, the genome does not get messages from the environment. Mutations are random (*yes they are, some mutations are more frequent than others, but for a given type of mutation we can say with what frequency we might expect it to occur but not exactly when it will occur, that is precisely the definition of a random variable*) and independent of the human-perceived needs of the organism. It’s a system of random generation of variability followed by selection, not a system of feedback and planned improvement, even though it powerfully simulates the latter, to human eyes.)

you’d think that editing the messages to remove some of the random ones would increase the chances that the meaningful messages would get through.

This implies a system in which the genome can only receive a limited number of messages per unit time. In the context of explaining what you mean by messages to the genome, why would this be the case?

Harold,

I’m not suggesting that the environment is anything like a mind or that what’s going on involves any Larmarckian or other mysterious mechanism other than the usual mutation + selection + drift, etc. I’m simply trying to think of evolution as a learning system. The messages the environment send takes the form of such things as it’s hot, it’s cold, food is missing, here’s a predator, etc. and the greeting inside the card is often “You’re dead!” or “You’re not going to be able to reproduce.” Where what I’m calling the environment’s messages don’t reflect regularities or trends to which the population can adapt by natural selection, the population can’t learn anything from them. The useless messages include events and conditions that wipe out the entire population, of course; but also random events which eliminate individuals at the same rate regardless of their genetic makeup or which are exceptional relative to general trends. If culturally inherited traits reduce the impact of useless messages on populations, will that change how quickly favorable mutations increase in frequency? If so, I wouldn’t expect the explanation to involve appeal to any kind of woo, but would be like one of those surprising results in economics that follows from the normal principles under certain conditions.

Creationists are perpetually claiming that evolution explains the development of living things by appeal to chance, to which the proper response is that only mutation is random. The environment isn’t random. If it were, there would be nothing to adapt to. Indeed, when the environment is too random, as sometimes occurs, the result is extinction. As it itself changes, the environment informs the process of natural selection. Which is why we can explain at least some evolutionary changes as adaptations. And that’s why I think it’s kosher to talk about random or non-random inputs from the environment. Kosher but not implying the hand of god!

Jim Harrison said:

Harold,

I’m not suggesting that the environment is anything like a mind or that what’s going on involves any Larmarckian or other mysterious mechanism other than the usual mutation + selection + drift, etc. I’m simply trying to think of evolution as a learning system. The messages the environment send takes the form of such things as it’s hot, it’s cold, food is missing, here’s a predator, etc. and the greeting inside the card is often “You’re dead!” or “You’re not going to be able to reproduce.” Where what I’m calling the environment’s messages don’t reflect regularities or trends to which the population can adapt by natural selection, the population can’t learn anything from them. The useless messages include events and conditions that wipe out the entire population, of course; but also random events which eliminate individuals at the same rate regardless of their genetic makeup or which are exceptional relative to general trends. If culturally inherited traits reduce the impact of useless messages on populations, will that change how quickly favorable mutations increase in frequency? If so, I wouldn’t expect the explanation to involve appeal to any kind of woo, but would be like one of those surprising results in economics that follows from the normal principles under certain conditions.

Creationists are perpetually claiming that evolution explains the development of living things by appeal to chance, to which the proper response is that only mutation is random. The environment isn’t random. If it were, there would be nothing to adapt to. Indeed, when the environment is too random, as sometimes occurs, the result is extinction. As it itself changes, the environment informs the process of natural selection. Which is why we can explain at least some evolutionary changes as adaptations. And that’s why I think it’s kosher to talk about random or non-random inputs from the environment. Kosher but not implying the hand of god!

Mutations are random Jim, but they are also constrained by the prior phylogenetic history of the population undergoing such mutation(s). That is why, for example, you would never expect to see a crocoduck, since the lineages leading to crocodiles and birds diverged at a time so remote that it wouldn’t be possible to have a mutation(s) that would result in such a chimera. This is an important point which creationists are ignoring.

Increase in population suggests a reduction in selection pressure, or, to state it another way, an increase in average fitness of the population. Human populations have been increasing rapidly. However the highest rates of increase are not in populations which have excellent medical care, but rather in the third, or fourth, or whatever world.

Past mass extinctions have resulted in extirpation or decimation of the dominant organisms (ignore the bacteria, please). Mass extinction is not just a matter of x number of random species being offed. Given this historical knowledge, and the conceit that we are the planet’s dominant species, we should, in fact, be quite concerned by the present rap-id rate of extinctions.

Gerard Arpey is the CEO of AMR the parent company American Airlines and has been in charge of some of the most egregious acts of disloyalty to the most important employees of the company.

About this Entry

This page contains a single entry by Nick Matzke published on March 30, 2011 11:46 PM.

Upcoming Seminar Series on genomics at University of Oregon was the previous entry in this blog.

Why it needed saying, UK style is the next entry in this blog.

Find recent content on the main index or look in the archives to find all content.

Categories

Archives

Author Archives

Powered by Movable Type 4.381

Site Meter