The relation between micro- and macroevolution

Discussions on general biology and biological evolution, genetics, zoology, ecology, botany, etc.

Re: The relation between micro- and macroevolution

Postby Reg_Prescott on February 17th, 2020, 11:19 pm 

davidm » February 18th, 2020, 12:17 am wrote:
Copernicus brought about a revolution because he completely overturned the prevailing model of Ptolemy. He replaced geocentrism with heliocentrism



A little off topic, but David, do you feel the Ptolemaic theory of geocentrism is true?

If not, what status do you assign it? Underloved?
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Re: The relation between micro- and macroevolution

Postby Reg_Prescott on February 17th, 2020, 11:35 pm 

TheVat » February 17th, 2020, 11:32 pm wrote:


Not really. Individual hypothesis may be false, but that's not a theory. At least not in the sense of "evolutionary theory. " A lot of a theory is an explanatory net drawn around a bunch of observations (tested hypotheses). When a key hypothesis is falsified, the integument of theory simply weakens, maybe to where it unravels. I mean, sure, sometimes people speak sloppily and say a whole theoretic model is "false" but it's really a pretty loose way of speaking. Which is why people get into conceptual trouble when they say stuff like "Newtonian theory of gravitation is false. "





I'm not gonna let you wriggle out of this so easily, Mr Vat :)

Now, let's take the theory of phlogiston as our example. Some facts I think we can both agree on to begin with:

1. Just about any scientist you ask nowadays will tell you, inasmuch as phlogiston -- as far as we can tell -- does not exist, the theory is false.

2. As often happens in scientific revolutions, (at least some) proponents of the old theory remain unconvinced of the virtues of the upstart new theory. Some say Joseph Priestley's last words were "It exists, dammit!".

Are we cool so far?

Now, due to problems that I've no doubt you're familiar with -- the Duhem-Quine thesis, the holistic nature of testing, etc -- I'd be hesitant of a claim that scientific theories can be demonstrated (in the logical sense = definitively logically proven) to be false.

But that's quite a different matter from whether or not the theory has a truth value (i.e. true or false), regardless of whether or not that truth value can be definitively ascertained.

The former is a matter of semantics; the latter a question of epistemology.

Do you think the theory of phlogiston has a truth value?

I think it does.
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Re: The relation between micro- and macroevolution

Postby TheVat on February 18th, 2020, 1:16 pm 

I'd say no. It's a model that is not applicable. It doesn't have enough basis, anymore, to even be wrong. It's like a set of assertions about the pointed tips of unicorn horns. There is no simple binary of T/F to statements about the pointiness of unicorn horns - the creatures don't exist, and one can say anything about the traits of such a nonexistent being without really touching on a truth value. We're in Biology here, not philosophy of science, so I don't expect much of this matters except so far as epistemology touches on what can be known from our observations of an external world.

As one respondent to the Moran blog (a worthwhile link from David, getting into neutral theory v adaptation) wrote...

My understanding is that the crux of the debate is quantitative - just how important is neutral evolution in comparison to adaptive? It's not that Dawkins is not aware of tongue rolling in humans, he just doubts there are many traits like this. Personally I am leaning toward very important, but I think the experimental answer to this question is not yet available. Without solid experimental foundation, the debate is essentially theological.
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Re: The relation between micro- and macroevolution

Postby Reg_Prescott on February 18th, 2020, 2:15 pm 

TheVat » February 19th, 2020, 2:16 am wrote:I'd say no. It's a model that is not applicable. It doesn't have enough basis, anymore, to even be wrong. It's like a set of assertions about the pointed tips of unicorn horns.


And anyone who has suffered through a course in the philosophy of language knows the first 5000 years are dedicated to examining the statement "The present king of France is bald".

Given that there is no present king of France, all agree (without exception, as far as I'm aware) that any assertion made about "him" cannot possibly be true.

(Whether it should be assigned a value of false, or neither true nor false is a matter of some dispute)

Assuming, likewise, that unicorns share the same ontological status as the present king of France (i.e., none) then nothing true can be asserted about them, horns and all.

Or are we supposed to believe that the proposition "all unicorns have pointy horns" somehow enjoys amnesty from truth and falsity?

Sounds to me about as false as it gets.

What would you say if your granddaughter asked, "Is it true that all unicorns have horns like a pencil sharpener?"

"Well, you see, it's just a model...."

C'mon, now, friend.
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Re: The relation between micro- and macroevolution

Postby TheVat on February 18th, 2020, 2:43 pm 

Fine, Reg. As I said, I'm not in a phil of sci mood, and we're in SCF, so I feel a pull back to topic. I hope I made clear what I meant in something being (In a science context) "not even wrong. "

Reading down that Sandwalk blog, the comments section is a refresher course all by itself on drift, neutral evolution and adaptationism. Several posts touch on how far we are from really drilling into how phenotypes like tongue rolling (I can roll mine) are derived from genotype - is this knack neutral, adaptive, in pleiotropic balance with some other trait? We really don't know enough to say how it comes about or if it might be adaptive at some point. (the simple two-allele account has been debunked as myth, btw) (perhaps a cultural change would effect multiple allele shifts, and require an explanatory path at odds with micro? I don't think so. It's all micro, below the level of entire species. )
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Re: The relation between micro- and macroevolution

Postby TheVat on February 18th, 2020, 3:09 pm 

Just as a sidebar, I want to clip this bit from a wiki called Units of Selection...

Gould proposed that there exist macroevolutionary processes which shape evolution, not driven by the microevolutionary mechanisms of the Modern Synthesis.[15] If one views species as entities that replicate (speciate) and die (go extinct), then species could be subject to selection and thus could change their occurrence over geological time, much as heritable selected-for traits change theirs over generations. For evolution to be driven by species selection, differential success must be the result of selection upon species-intrinsic properties, rather than for properties of genes, cells, individuals, or populations within species. Such properties include, for example, population structure, their propensity to speciate, extinction rates, and geological persistence. While the fossil record shows differential persistence of species, examples of species-intrinsic properties subject to natural selection have been much harder to document.
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Re: The relation between micro- and macroevolution

Postby davidm on February 18th, 2020, 3:13 pm 

NOTE: Some of this will be off-topic for the thread, but I am responding to stuff Reg wrote to me since yesterday, which necessitates a little off-topic stuff. We could alway split some of these to other threads, such as the discussion of where truth values inhere.

Reg,

I haven’t the time right now for a comprehensive post, so I’ll start with this, since you asked me to:
Would you puh-lease point to the place where I imputed an endorsement of falsificationism to you? Be a good chap and do that right now. If you can't, an apology or a Lamborghini will be just fine.

You had written as follows:

If theories cannot be true or false, why do I hear so much talk about such-and-such a theory (phlogiston, say, or Ptolomaic geocentrism) having been falsified? If a theory has indeed been falsified, then it's, um, false, right?


Here, you were directly responding to Vat, who had written:

Theories aren't true, they are models that …


Since he said pretty much the same thing I said, you were, in effect, responding to me as well as to him.

To me, your implication is clear: It is contradictory to hold that theories can be neither true nor false, while at the same subscribing to falsificationism. If you did not intend to impute, to Vat or me, an endorsement of falsificationism, then why bring this up, in response to Vat’s (and my) claim?

I do not think falsificationism is sufficient criterion for theory-evaluation, and I doubt it is even a necessary one. If it were, all string theorists should quit work at once. But since you raise the point, I will say that falsificationism, even if it has a domain of applicability, does not necessarily make a theory false, even if theories can be said ever to be, strictly, “false” or “true.”

I believe that you, yourself, brought up, in this thread or another, the anomalous orbit of Mercury. Did this anomaly “falsify” Newtonian mechanics?

As it happens, earlier, a similar anomaly was spotted in the orbit of Uranus. If we were to take falsificationism literally, of course, we should have then and there declared Newton’s theory dead in the water.

Instead, quite sensibly, Newtonians said that the “falsification” itself was anomalous, and posited the existence of a planet beyond Uranus, even indicating about where Newton predicted it would be found. Lo and behold, Neptune was found.

When the Mercury anomaly popped up, people therefore even more sensibly predicted it could be explained in terms of another planet not yet found, this one orbiting the sun closer than Mercury. Even before finding this planet, they gave it a name, Vulcan, because they were so confident it would be found. But it was not found.

The rest, as they say, is history.

But does the Einstein revolution mean that Newtonian mechanics is false? I do not think so. I think it means that Newton’s dynamics were found to have a restricted domain of applicability. If Newtonian mechanics was false, in the binary way (true/false) used in ordinary discourse, then why is it still taught in school? Why is it still used to plot trajectories of spacecraft to other planets? Why is it still used for all sorts of workaday stuff? Because it is useful, and predictive, to certain limits, those limits being where high-speed (relativistic) physics, and micro-world (quantum) physics, take over.

And we know something will have to take over for general relativity and quantum physics, because the two theories, while spectacularly successful, are not on speaking terms — hence, one or both are ripe to be subsumed under some yet-undiscovered overarching theory. But that does not mean that either GR or QM will be false — only limited in their domains of applicability, like Newton’s theory.

And, since you asked later, I might as well answer now: No, I don’t think it’s fair to say that Ptolemy’s geocentric theory, per se, is false. For my understanding, theories are epistemologies (maps) of the way that the world is (ontologies). I think that ontologies are true or false. Epistemologies (maps) are updated to reflect new understanding of ontologies. Now this, admittedly, is disputable. Under the correspondence theory of truth, for example, truth values inhere, not in the world itself, but only in propositional statements about the world. And theories certainly are forms of propositional statements. I think that’s an interesting discussion in its own right — where does truth inhere (if it inheres anywhere)? But I think it is far afield for this thread; indeed, the entire topic now under exploration is already far afield from the thread topic.

So is the geocentric model strictly false? Ptolemy’s model was empirically equivalent to Copernicus’s model, and worked impeccably for more than a thousand years. I daresay it would even work today, for calculation purposes, if updated somewhat. What more can you ask of a model?

What is false, however, is not the model, but that the sun actually revolves around the earth. As it happens, it is also false that the earth revolves around the sun. They revolve around a common center of gravity very close to the sun.

More later, as I find time. Your attitude seems to be (somewhat) improved in your latest responses; if you keep that up, perhaps we can actually have a useful and mutually enlightening — dare I say even friendly? — discussion. :-)
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Re: The relation between micro- and macroevolution

Postby davidm on February 18th, 2020, 3:32 pm 

Reg_Prescott » February 17th, 2020, 8:40 pm wrote:
davidm » February 18th, 2020, 12:17 am wrote: he [moi] labels evolutionary theory “BS” and derides natural selection and survival of the fittest as empty tautologies. If that were true, then both phyletic gradualism and Punk Eek could not take place


They couldn't take place because I deride them? Or because they are tautologies? Happens all the time, pal. Que sera sera. Whatever will be will be. What happens happens. If you have any doubts, try to stop what will happen from happening. It's just not very informative, that's all.


This is non-responsive. You know what I mean.

You extol Punk Eek (which I have no problem with).

But you have also said that evolutionary theory introduced by Darwin is "BS" and that natural selection and survival of the fittest are tautologies.

Is it not so that punk eek is just another model of common descent and natural selection? Does Gould reject either? Yes? No?

How could Punk Eek or phyletic gradualism have any leg to stand on, without common descent and natural selection as their floor? Please explain.
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Re: The relation between micro- and macroevolution

Postby davidm on February 18th, 2020, 3:37 pm 

I should say, for the purpose of clarity: If you are saying Darwin's original theory is "BS" in the colloquial sense that we have gone way beyond him, I AGREE. I have said just that, again and again. Darwin, obviously, did not know about all sorts of stuff -- basic genetics, to take one of many examples.

But that certainly does not seem to have been what you said -- especially when you talk about selection and survival of the fittest being "tautologies," when again, they clearly aren't. Again, please explain.
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Re: The relation between micro- and macroevolution

Postby Reg_Prescott on February 18th, 2020, 11:36 pm 

davidm » February 19th, 2020, 4:37 am wrote:
But that certainly does not seem to have been what you said -- especially when you talk about selection and survival of the fittest being "tautologies," when again, they clearly aren't. Again, please explain.


Well, once again, David, you seem frightfully sure of yourself.

How, then, do you explain J. B. S. Haldane (just to name one) saying exactly what I say: that natural selection is a tautology?

What was his problem? Too much gin and absinthe?

Now, it's a wee bit off topic, but if the handsome, muscular mods will permit us, why don't you state the principle of natural selection for us in a non-tautological manner.

I'm quite willing to be proven wrong.
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Re: The relation between micro- and macroevolution

Postby Reg_Prescott on February 18th, 2020, 11:48 pm 

To add a little more: to escape the charge of "survival of the fittest" being tautologous, you would have to characterize fitness without any reference to survival and reproduction.

Otherwise we're stuck in a vicious loop of "Those more able to survive and reproduce successfully (and transmit their genetic material, etc., etc) tend to... er, survive and reproduce more successfully than those less able".

Now, if we zoom in to, say, ring-tailed lemurs, one might advance the hypothesis "Ring-tailed lemurs (in such-and-such an ecology) with relatively shiny noses tend to survive and reproduce more successfully than their matt-nosed brethren".

This is a perfectly respectable, non-tautologous, empirical (cf. scientific) hypothesis. It may be true or it may be false (for those dinosaurs like me who believe in such things), but the only way we could find out is by getting our hands dirty out there in the Madagascar jungle. Its truth or falsity cannot be determined just by sitting on the couch and thinking.

But natural selection is not a theory/hypothesis specifically about ring-tailed lemurs: it purportedly applies to all organisms/species.

Now try generalizing and see what happens.
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Re: The relation between micro- and macroevolution

Postby Reg_Prescott on February 19th, 2020, 12:10 am 

davidm » February 19th, 2020, 4:13 am wrote:The rest, as they say, is history.

But does the Einstein revolution mean that Newtonian mechanics is false? I do not think so. I think it means that Newton’s dynamics were found to have a restricted domain of applicability. If Newtonian mechanics was false, in the binary way (true/false) used in ordinary discourse, then why is it still taught in school? Why is it still used to plot trajectories of spacecraft to other planets? Why is it still used for all sorts of workaday stuff? Because it is useful, and predictive, to certain limits, those limits being where high-speed (relativistic) physics, and micro-world (quantum) physics, take over.



Again, a bit off topic, but an interesting point (if the sexy mods will indulge us).

When you speak of "It's not false. We've just discovered that its domain of applicability is limited", it sounds to me an awful lot like saying "My theory that all mammals give birth to live young is not false. Er, all you have to do is avoid Australia".

Nicholas Rescher puts it this way:

"It may seem tempting to say that later theories simply provide localized readjustments and that the old theories continue to hold good provided only that we suitably restrict their domains of purported validity. On such a view, it is tempting to say: "Einstein's theory does not replace Newton's; it does not actually disagree with Newton's at all but simply sets limits to the the region of phenomena (large-scale, slow-moving objects) where Newton's theory works perfectly well". Such temptations must be resisted. To yield to them is like saying that "All swans are white" is true all right; we just have to be cautious about its domain limitation and take care not to apply it to Australia. This sort of position comes down, in the final analysis, to the unhelpful truism that a theory works where a theory works."


As to "Why is it [Newtonian mechanics] still taught in schools?" (etc.), the answer is, as you rightly note: it works. It works extremely well.

Now, by working I mean it is (strictly speaking, if you insist) a false theory, but one from which very accurate predictions can be derived.

Not at all unlike Ptolomaic cosmology: you could navigate your way to Madagascar using it. Another example of a false theory from which accurate predictions can be derived.

But, taking the ontology of the theory into account, is it true that the Sun revolves around the Earth within a system of nested, concentric, crystalline spheres, and all the rest?

I don't think so. Same goes for Newtonian mechanics IMO.

Is it true that there exists an attractive property inherent in all massive objects that acts instantaneously over any distance against a backdrop of absolute space and absolute time?

Well, there must be a few physicists around here somewhere. Why don't we ask them?
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Re: The relation between micro- and macroevolution

Postby Reg_Prescott on February 19th, 2020, 12:34 am 

davidm » February 19th, 2020, 4:32 am wrote:
You extol Punk Eek (which I have no problem with).




Not exactly. Let me clarify my position.

Gould and Eldredge strike me as both extremely sophisticated, intelligent men, thus worthy of our attention, even if they turn out to be wrong (happens a lot).

I alluded earlier to a distinction between the pattern and the process of punctuated equilibrium.

If the paleontologists are right (and Gould has quotes galore to support him), then it does seem that the Darwinian doctrine of slow, steady, gradualistic evolution is just plain false. It would appear that most species do little or no evolving at all through the millennia. Stasis, as opposed to evolutionary activity, would appear to be the rule rather than the exception.

To this -- the pattern -- I happily add my endorsement. And good work, chaps.

As for process, on the other hand, well, I'm not gonna make any friends, but the whole idea of selection -- whether it be at the level of individual organisms, genes, groups, sexual selection, kin selection, entire species, or worst of all, memes (Gosh, I don't like that Dawkins fellah at all) -- strikes me as manifestly absurd.

Hey, wanna get tenure? Just invent a new level of selection.


P.S. I could, of course, be hopelessly wrong. That happens a lot, too.
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Re: The relation between micro- and macroevolution

Postby Forest_Dump on February 19th, 2020, 11:02 am 

I think there might be a few more facets that could be clarified. First, as I see it, phyletic gradualism (P-G) and Punctuated equilibrium (P-E) might be seen as simply just the patterns seen at different scales. P-G might work best at the grossest scale in much the same way that we could say that the economy has improved over the last 500 years as measured by the amount and quality of food available, ease of travel, comfort of the home etc. But looked at more closely P-E seems more the rule because of various chance events which can include everything from rate of mutations to the occurrence of catastrophic events such as collisions from meteorites or big events caused by plate tectonics, etc. As I mentioned, random doesn't mean "even" but more often clumps and gaps. You get the same kind of P-E in economics as seen in day-to-day fluctuations in the stock market up to the bigger ones like in 1929 or 2008, etc. Even these do not mean that overall things are not improving.

But of course, P-G vs. P-E are a product of being able to measure something. We should know that there are many things that have evolved over time that are simply not preserved in the fossil record. Those periods of seeming stasis could well have been times of rapid change in some of the many other attributes of life that do not preserve well but we know happened from changes in colour to ability to digest, resist diseases, etc.

As you said, an important point is to recognize the difference between pattern and process. P-G vs. P-E are simply descriptions of different patterns and do not really get at the process although obviously the different protagonists in the cited debates do not really disagree on the processes involved although they do disagree on the scaling of different ones.

As an example, I do not think ANY serious biologist or palaeontologist, etc., disagrees that natural selection is ONE important process or force at play. What is debated is how the idea is used (I would strongly dispute things like Dawkin's characterization of natural selection as being creative, etc., since I think he lumps in sources of variation with natural selection which only removes lesser variants in perhaps very complicated ways). And I am one who thinks there are other evolutionary forces/process such as drift (chance), gene flow, etc. that are at least sometimes stronger that natural selection. It becomes a very tricky argument to say that some critters might be better adapted to survive a meteor strike but it could be done.
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Re: The relation between micro- and macroevolution

Postby TheVat on February 19th, 2020, 2:03 pm 

All my meteor adaptations are spandrels.
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Re: The relation between micro- and macroevolution

Postby davidm on February 19th, 2020, 2:38 pm 

How, then, do you explain J. B. S. Haldane (just to name one) saying exactly what I say: that natural selection is a tautology?


Can you tell me where Haldane said that, with the relevant context?

… why don't you state the principle of natural selection for us in a non-tautological manner.


Imagine a toy universe. One of its lineages consists of yellow balls, or ball-like creatures, that roll around on a mostly flat yellow surface of nutritious soil. The balls are covered with tiny pucker mouths that feed off the soil as they roll.

They are beautifully adapted in three ways: Their ball shapes facilitate easy rolling locomotion over a mostly flat surface. Their pucker mouths make it easy for them to find food in the soil as they roll. And finally, their color matches the color of the surface. This is important because among their predators are birds that wheel overhead in search of the balls. But the balls are camouflaged: Color matches surface. They are hard for the birds to see, and therefore hard for them to prey on.

Question: how did they get this way?

As it happens, the balls reproduce with variation, undergo mutations, and evolved over many generations from distant ancestors.

Because they reproduce with variation, some balls may be born with a mutation that gives them, say, a splotch of red on their yellow skins. Some of them may be born with a variation that extends some of the pucker mouths outward, like — I dunno. Little proto-legs?

The proto-legs, which they get by chance variance alone, are probably no big deal. They do impede their rolling somewhat, but again, the terrain is not completely flat — there are bumps and gullies here and there — and what these offspring lose in ease of locomotion across the flatness, they may gain in extra traction in pulling themselves out of small gullies, or pulling themselves up over little hills, an advantage that their rounder brethren will lack. By and large, the proto-leg variation is probably neutral, one advantage canceling out one disadvantage. They are still less likely to be eaten by the birds, and thus are more likely (though by no means certain) to live long enough to reproduce and pass on their proto-leg trait.

The red-splotch offspring, however, are not likely to be as fortunate. They are easier for the birds to spot, and hence it is more likely that they will be eaten. This means it is less likely for them to live long enough to pass on the red-blotch trait — i.e., it is more likely that they will be less fit — they will have less reproductive success. Their red blotch is a deleterious variance. The other mostly yellow balls, and the mostly yellow balls with proto-legs that may impede locomotion on the one hand, but improve it on the other, will therefore be more likely to leave more offspring with their heritable traits — i.e., they will be more fit. This is survival of the fittest.

Could you please identify the tautology here?

It would be an empty tautology to say something like, “survivors survive.” But that is not what my toy model is showing, or saying. Agree? Disagree? Why or why not?

“Survival of the fittest” is not just a statement that there is reproductive success, but explains why this is so. A theory that explains an observation cannot be a tautology, by definition.

And my toy model, of course, is just simplified Darwinian natural selection. I can extend the model, but first I await your reply.
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Re: The relation between micro- and macroevolution

Postby doogles on February 19th, 2020, 6:09 pm 

Good example david m. I was wondering when someone was going to get down to a concrete example, so that each contributor would know exactly what the other was talking about.
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Re: The relation between micro- and macroevolution

Postby TheVat on February 19th, 2020, 7:18 pm 

To be fair, they did discuss the Gouldian shark tooth example a couple days ago. And the likelihood that the change would be neutral evolution, rather than adaptive. Similar comments touched on tongue rolling and its neutrality. There's three pages, with many longish posts, so it's easy to miss things.

David shows where the adaptationist perspective matters (as I did elsewhere with the moths in Birmingham). Adaptationism can sometimes explain things quite clearly by observing how the environment offers particular hazards. Red splotch balls in Toy land, or pale moths on sooty English trees, your days will be few.

(my auto-correct keeps going off the rails... I typed Toyland, which it sneakily changed to Rutland, and didn't see till I returned hours later)
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Re: The relation between micro- and macroevolution

Postby Reg_Prescott on February 19th, 2020, 8:29 pm 

doogles » February 20th, 2020, 7:09 am wrote:Good example david m. I was wondering when someone was going to get down to a concrete example, so that each contributor would know exactly what the other was talking about.



It may or may not be a good example.

The problem is, I didn't ask Davidm so state an example of the principle of natural selection.

I asked him to state the principle of natural selection.

Reg_Prescott » February 19th, 2020, 12:48 pm wrote:
Now try generalizing and see what happens.
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Re: The relation between micro- and macroevolution

Postby Reg_Prescott on February 19th, 2020, 11:05 pm 

davidm » February 20th, 2020, 3:38 am wrote:
How, then, do you explain J. B. S. Haldane (just to name one) saying exactly what I say: that natural selection is a tautology?


Can you tell me where Haldane said that, with the relevant context?




I came across the Haldane quote in Phillip Johnson's (yes, yes, I know he's a Creationist) "Darwin on Trial". Johnson, in turn, directs us to Norman Macbeth's "Darwin Retried" (1971) where apparently several similar quotes have been collected.

(This is a book I've been eager to get hold of for some time. But Amazon is asking silly prices, never mind the extortionate shipping fees to Taiwan. Grr!. Er, anyone got a spare copy? )

Besides that, I'm not able to offer any context.

But hey, Haldane (assuming the quote is genuine) and myself are hardly the first people to suspect natural selection of being a tautology, hence explanatorily vacuous.

Take a look at the article "Dogma and Doubt" by R. H. Brady for an overview of the brouhaha. Though I've read it before, right now, unfortunately, I can only seem to get access to the abstract online. Maybe someone more computer-savvy than myself can help.

Anyway, in the opening paragraph, Brady offers a fairly impressive list of thinkers who have raised the same suspicions as myself.
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Re: The relation between micro- and macroevolution

Postby Reg_Prescott on February 19th, 2020, 11:19 pm 

davidm » February 20th, 2020, 3:38 am wrote:

“Survival of the fittest” is not just a statement that there is reproductive success, but explains why this is so. A theory that explains an observation cannot be a tautology, by definition.



I'd say -- in the form of a general principle -- it explains precisely nothing.

If the "fitter" just are those who survive and reproduce relatively successfully, then you would be "explaining" success in survival and reproduction by appeal to success in survival and reproduction. In other words, not explaining anything at all.

Here's another quote from Phillip Johnson's book:

". . . those individuals that have the most offspring are by definition . . . the fittest ones"

- Ernst Mayr (1963)
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Re: The relation between micro- and macroevolution

Postby TheVat on February 20th, 2020, 1:24 am 

Reginald,

You can't construct an argument with one liners, on a subject like this. Nor can any evolutionary theory really manifest its explanatory powers by catchy phrases like survival of the fittest. That's a strawman that's been gone over already. I see you shy from concrete examples others offer - is that because such examples reveal the actual explanatory power of theory and the specific mechanisms in the organism's interaction with its environment? Theories seek to make sense out of specific observations, so it's a strawman to treat them as solely aphorisms of a general form. It is you who is concocting the tautology, and making the explanation vacuous.
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Re: The relation between micro- and macroevolution

Postby doogles on February 20th, 2020, 2:12 am 

Reg_Prescott -- "The problem is, I didn't ask Davidm so state an example of the principle of natural selection.

I asked him to state the principle of natural selection."

IMO, he presented a good hypothetical example of 'natural selection', which explained the principle involved, without any need at all to state that principle.

Is it important to you that he should state that principle in actual abstract terms?
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Re: The relation between micro- and macroevolution

Postby Reg_Prescott on February 20th, 2020, 2:33 am 

@ TheVat and Doogles

I don't seem able to get my point across. Let me try one more time (and then, if I'm still getting nowhere, I'll put the proverbial sock in it. LOL)

Let's start off with the (imaginary) sad news that ten patients have died in the hospital this week: Mr A - Mr J.

Can a substantive (i.e., non-vacuous, non-tautological) causal-explanatory account be given for Mr A's demise? Of course. Cancer, say.

Can an explanatory account be given for Mr B's demise? Of course. Corona virus, say.

[...]

Can an explanatory account be given for Mr J's demise? Of course. Cirrhosis, say.


So far so good. Next question: Can their respective deaths be subsumed under a general overarching principle or law? A death force, perhaps, or some kind of death selection?

Suppose some bright spark proposes the hypothesis: "According to my theory of death selection, all else being equal, those people with conditions liable to cause death die before those without such conditions".

How would you react? Groan? Giggle? That makes two of us.

But, as I see things anyway, this is exactly analogous to natural selection when stated as a general principle, roughly "Those organisms with traits relatively conducive to survival and reproduction survive and reproduce more successfully than those without".

TheVat » February 20th, 2020, 2:24 pm wrote:Reginald,

I see you shy from concrete examples others offer - is that because such examples reveal the actual explanatory power of theory and the specific mechanisms in the organism's interaction with its environment?


Call it shying away if you like. Perhaps you have Davidm's most recent anecdote about ball-like creatures in mind? The reason I "shied away" is because David's response is irrelevant to what I requested of him, to wit:

Reg_Prescott » February 19th, 2020, 12:36 pm wrote:. . . why don't you state the principle of natural selection for us in a non-tautological manner.


David spun a yarn -- albeit charming -- about ball-like creatures on some faraway planet. What he did not do is state the general principle of natural selection, as I asked him to. Natural selection is not a theory/principle/law (whatever you want to call it) specifically about lions, elephants, or extraterrestrial ball-like creatures; it purportedly applies to all species.

At the end of his anecdote, David asked:
davidm » February 20th, 2020, 3:38 am wrote:
Could you please identify the tautology here?


There is no tautology, David. But you didn't do what I asked you to do, namely, state the principle of natural selection. It's the difference between a general hypothesis of the form "All F's are G" and you nudging me and exclaiming "Look! There's an F that is G". It's the former I want from you, not the latter.

Analogously, there is nothing tautologous about the individual causal-explanatory accounts of the deaths of Mr A, Mr B, et al. Tautology enters the picture only when we generalize. You didn't.


So, in conclusion, is there a substantive causal-explanatory story to be told for why (we shall suppose) shiny-nosed ringtailed lemurs survive and reproduce more successfully than their matt-nosed conspecifics? You bet.

(And what does the explanatory work is the shininess of the nose; not some vacuous principle of natural selection. Similarly, what explains Mr A's death is cancer; not some vacuous truism about "death selection".)

Is there a substantive causal-explanatory story to be told for why yellow ball-like creatures survive and reproduce more successfully than their red conspecifics? You bet again.

[add your own examples here, ad infinitum]

Finally, is there an all-encapsulating explanatory story to be told for what all these cases have in common that is not utterly vacuous?

I don't think so.

"Well, you see, they all have features which help them to survive, reproduce and increase in numbers, so they tend to ... er, survive, reproduce and increase in numbers".

*cough cough*

Can you do better?
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Re: The relation between micro- and macroevolution

Postby TheVat on February 20th, 2020, 11:12 am 

The theory says more, however. Let's stay in the domain of microevolution here, and at the level of the gene. NS doesn't JUST say that fitness survives (yes, of course that's tautology), it goes on to say HOW that particular gene came to be in the genome. Maybe it started as neutral mutation, resided in the genome a long while, then suddenly it became adaptive, indeed was fiercely selected for, then it's numbers soared from ten percent to 95 percent. That's one of the narratives that NS unleashes, and it's not tautological, in fact it's interesting and shines a light on why all those Norwegians were switching from boiled bone broth to cow's milk and getting laid all the time. The NS summation isn't tautological because it's driving those interesting explanations. And unlike, say, Lamarckian Theory, the explanation makes sense of our actual observations. It makes sense of a change in allele frequency. What more could you want?
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Re: The relation between micro- and macroevolution

Postby davidm on February 20th, 2020, 11:16 am 

Sigh. And … down the rabbit hole we go.

Reg, you admit that you can spot no tautology in my example. Yet, my example just IS natural selection/survival of the fittest in action. So if there is, as you admit, no tautology in my example, then, as a matter of sheer logic, there can be no tautology in any general principle serving as a definition of survival of the fittest.

You are now, in effect, saying: There is no tautology in survival of the fittest, but the survival of the fittest is a tautology.

See the problem?

But, as it happens, I already gave you, in the other thread that is now locked, a link to just what you asked for.

Here is the relevant passage:

…natural selection does not simply state that "survivors survive" or "reproducers reproduce"; rather, it states that "survivors survive, reproduce and therefore propagate any heritable characters which have affected their survival and reproductive success". This statement is not tautological: it hinges on the testable hypothesis that such fitness-impacting heritable variations actually exist (a hypothesis that has been amply confirmed.)


Bold is mine.

If you want me to put the matter in my own words, I would say:

Since organisms empirically reproduce with heritable variation, some of them will inherit variations that happen to be better adapted to the given environment (make them less likely to be eaten). Others will inherit variations that make them less well adapted (they will be more likely to be eaten). On average, the better adapted individuals will be more likely to survive long enough to reproduce, and thus pass on the adaptive variations that they were fortunate enough to inherit. These traits will consequently begin to spread through the population. This is called “survival of the fittest.” And this, in nature, is exactly what we observe.

Where is the tautology, Reg? Where?

Note that my toy model illustrates my principle of natural selection, which I have just supplied to you, in concrete terms. And remember, you have just admitted that there is no tautology in my example. Therefore there can be no tautology in the principle that you asked for, and which I have now given you. As mentioned, I can extend the example too, if you like.

Now you had claimed that Haldane wrote somewhere that survival of the fittest is a tautology. When I asked you to show me the exact quote with its context, you admit you can’t do it! Is this honest discussion?

Now it’s on to Ernst Meyer!

“… those individuals that have the most offspring are by definition … the fittest ones”


Reg, where is this quote from? What is its context? And what is behind the ellipses?
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Re: The relation between micro- and macroevolution

Postby davidm on February 20th, 2020, 1:06 pm 

I recommend this strong discussion by the evolutionary biologist John A. Endler from his book Natural Selection in the Wild: Natural Selection and Tautology.

Note this key point:

"Survival of the fittest" is certainly a tautology; but it completely misses the point of natural selection and confuses cause and effect.


Well ... yeah! Sure, fine, "survival of the fittest" by itself is a tautology -- but in evolutionary theory, it is never by itself. And I have no doubt that the quotes by Haldane and Mayr that Philip Johnson cherry-picked for inclusion in his book Darwin on Trial made that very point, when given their larger context that Johnson does not give, and made it clearly! (Yes, both cherry-picked quotes invoked by Reg were in Johnson's terrible book.)

Are we done here with this tautology BS?
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Re: The relation between micro- and macroevolution

Postby TheVat on February 20th, 2020, 1:46 pm 

Let's get back to SJ Gould's statement on micro/macro and see where we are with that, shall we?

First, punctuated equilibrium secures the hierarchical expansion of selectionist theory to the level of species, thus moving beyond Darwin's preference for restricting causality effectively to the organismic realm alone (leg one on the essential tripod). Second, by defining species as the basic units or atoms of macroevolution--as stable "things" (Darwinian individuals) rather than as arbitrary segments of continua--punctuated equilibrium precludes the explanation of all evolutionary patterns by extrapolation from mechanisms operating on local populations, at human timescales, and at organismic and lower levels (leg three on the tripod of Darwinian essentials). Thus, as emphasized in the last section, punctuated equilibrium presents no radical proposal in the domain of microevolutionary mechanics--in particular (and as so often misunderstood), the theory advances no defenses for saltational models of speciation, and no claims for novel genetic processes. Moreover, punctuated equilibrium does not attempt to specify or criticize the conventional mechanisms of microevolution at all (for punctuated equilibrium emerges as the anticipated expression, by proper scaling, of microevolutionary theories about speciation into the radically different domain of "deep" or geological time). But punctuated equilibrium does maintain, as the kernel of its potential novelty for biological theory, that those unrevised microevolutionary mechanisms do not hold exclusive sway in evolutionary explanation, and that their domain of action must be restricted (or at least shared) at the level of macroevolutionary pattern over geological scales--for punctuated equilibrium ratifies an effective realm of macroevolutionary mechanics based on recognizing species as Darwinian individuals. In other words, punctuated equilibrium makes its major contribution to evolutionary theory, not by revising microevolutionary mechanics, but by individuating species (and thereby establishing the basis for an independent theoretical domain of macroevolution).
- PE, SJG, p. 58

Is this separation of domain legitimate? Is the extrapolationist view going to break down when we reach the unit level of whole species? And, my earlier clip....

If one views species as entities that replicate (speciate) and die (go extinct), then species could be subject to selection and thus could change their occurrence over geological time, much as heritable selected-for traits change theirs over generations. For evolution to be driven by species selection, differential success must be the result of selection upon species-intrinsic properties, rather than for properties of genes, cells, individuals, or populations within species. Such properties include, for example, population structure, their propensity to speciate, extinction rates, and geological persistence. While the fossil record shows differential persistence of species, examples of species-intrinsic properties subject to natural selection have been much harder to document.
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Re: The relation between micro- and macroevolution

Postby davidm on February 20th, 2020, 7:30 pm 

While the fossil record shows differential persistence of species, examples of species-intrinsic properties subject to natural selection have been much harder to document.


Well, that’s the point, right? What is the current state of the evidence for this? Still, as Gould would acknowledge, species-level selection, or even selection at higher levels, does not invalidate Darwin’s key insights of common descent and natural selection. If anything, it amplifies those insights by taking them to higher levels.

In The Structure of Evolutionary Theory, Gould discusses:

… several clades of Tertiary gastropods show trends to substantial decrease in relative frequency of species with planktotrophic larvae vs. species that brood their young. In one common explanation (by no means universally accepted), this reduction occurs by species sorting based on the lower speciation rate of planktotrophic species — an hypothesized consequence of the lower probability for formation of isolates in species with such widespread and promiscuous larval dispersal. The sorting clearly occurs by selection, since low speciation rate arises as a consequence of interaction between traits of interactors and their environment. But at what level does selection occur?


Now he goes on with the discussion, found here (starting on page 660).

Later he writes:

Finally, we may seal the case by citing Grantham's important argument (1995, p. 301) that "species selection does not require emergent traits because higher-level selection acting on aggregate traits can oppose lower-level selection." Vrba herself has argued (1989, p. 80) that "the acid test of a higher level selection process is whether it can in principle oppose selection at the next lower level." Surely such an opposition can arise "in principle" (and probably in actuality) in this case-for planktotrophy could be positively selected at the organismic level, but may, through its strong effect on population structure, and the resulting consequences for rates of speciation, enjoin negative selection at the species level.


Gould goes on:

To summarize, we all agree that an independent theory of macroevolution must identify higher-level causal processes that are not reducible to (or simple effects of) causes operating at conventional lower levels of gene and organism. This premise defines the theoretical salience of the debate about species selection — for if such a process exists, and can also be validated as both common in evolution and irreducible in principle, then macroevolutionary theory has been achieved. For this reason, evolutionary biologists, who usually eschew academic philosophy (as the mildly philistinistic culture of science generally dictates), have joined in such classical philosophical debates as the meaning of reduction and emergence.


Love the “mildly philistinistic culture of science” vis a vis philosophy bit. :-) Hawking writes a book in which, on page one, he declares: “Philosophy is dead.” Then, oblivious to the irony, he goes on to write a book about … philosophy.
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Re: The relation between micro- and macroevolution

Postby Reg_Prescott on February 20th, 2020, 7:49 pm 

davidm » February 21st, 2020, 12:16 am wrote:Reg, you admit that you can spot no tautology in my example [of extraterrestrial ball-like creatures]. Yet, my example just IS natural selection/survival of the fittest in action. So if there is, as you admit, no tautology in my example, then, as a matter of sheer logic, there can be no tautology in any general principle serving as a definition of survival of the fittest.

You are now, in effect, saying: There is no tautology in survival of the fittest, but the survival of the fittest is a tautology.



Compare (with reference to my theory of "death selection", posted above):

Dear Death Selection Denier. You admit that you can spot no tautology in my example [of Mr A dying of cancer]. Yet, my example just IS death selection in action. So if there is, as you admit, no tautology in my example, then, as a matter of sheer logic, there can be no tautology in any general principle serving as a definition of death selection.

You are now, in effect, saying: There is no tautology in death of the most moribund, but the death of the most moribund is a tautology.


davidm » February 21st, 2020, 12:16 am wrote:Are we done here with this tautology BS?


Are we done here with my death selection being a tautology BS?
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