Is the theory of punctuated equilibrium a gamechanger for evolutionary biology?

[Pinball1970]

Just a correction "What Evolution is," is E Mayr. My spell check prefers "Mary" for that combination.

 

[axocanth]

Does he have a little lamb?

 

[Pinball1970]

Hmm, so the implication is it's quite an arcane issue, debated among experts but with little impact on the essentials of the theory. Much as I suspected.

Yes, caused a stir in the 1970s but now is not in an overview. I will check more though.
I also need to check what the great man himself said about his own theory.
I have two books from him but I find him difficult to read, he is obsessed with baseball!
I am not interested in Baseball so I really do not want a description of it in an intro to a biology book.
Imagine if Dawkins wrote a book on Evolution and the intro was about cricket?
His publisher would certainly have words!

 

[axocanth]

Lol! Yeah, he does talk about baseball a lot. Not very interesting to we limeys.

You won't do much better than his 2007 "Punctuated Equilibrium" for an overview of recent discussions here. Honestly, I don't have strong opinions either way. I just like learning about it. How about you?

 

[Pinball1970]

Lol! Yeah, he does talk about baseball a lot. Not very interesting to we limeys.

I just hate long winded analogies, by the time you have explained them, you may as well just have taken the time to talk about the science.
They can be useful if used sparingly.

You won't do much better than his 2007 "Punctuated Equilibrium" for an overview of recent discussions here

I will check that out thanks.

 

[exchemist]

Yes, caused a stir in the 1970s but now is not in an overview. I will check more though.
I also need to check what the great man himself said about his own theory.
I have two books from him but I find him difficult to read, he is obsessed with baseball!
I am not interested in Baseball so I really do not want a description of it in an intro to a biology book.
Imagine if Dawkins wrote a book on Evolution and the intro was about cricket?
His publisher would certainly have words!

Might sell well in S Asia, though.

 

[C C]

[...] Scientists meanwhile continue, as a matter of course, to spread the untruth -- whether known to them or not -- that scientific theories can be falsified, indeed, they continue, this is precisely what distinguishes science from pseudoscience, metaphysics, "woo" stuff, religion, or whatever.

[...] Obviously, appeal to falsifiability or unfalsifiability is almost irresistible in its seductiveness, allowing scientists to dismiss out of hand anything they don't like. -- "It's unfalsifiable, therefore it's not science, therefore it's crap." [...] How about you, CC? Any thoughts?

Theoretical constructs that cover or help explain a broad variety of things obviously aren't going to be abandoned or significantly disparaged in importance because of one of their predictions (or whatever) being falsified in one of those particular nooks. And some continue to be invaluable tools, like Newton's innovations not becoming obsolete.

The social or "human" sciences can potentially sport a host of items that are too ambiguous to be subjected to robust refutation. (Like the humanities, many of its practitioners are often fans of everything intellectually descended from Marx and Freud -- a couple of the very things Popper selected as examples of dogmatic pseudoscience.)

And because a main hypothesis may sometimes need support from background assumptions (auxiliary hypotheses), reciprocal tweaks in the latter may allow it to stay in play as a contender, after a test fail. Or again -- like an octopus, maybe it has so many arms prowling in various areas that chopping one off doesn't kill the beast.

Which is to say, falsifiability certainly wouldn't be universal and unbiased in application. Similar to "science methods", the working or grunt scientists may often break the prescriptions and descriptions issued by philosophers.

But falsifiability can still be a pragmatic justification for not wasting time researching various folk beliefs and blatant varieties of futile or bogus propositions. Akin to how business principles dealing with efficiency and personal conduct -- despite being artificial in origin and enforced by employment contract (rather than discovered under a rock or decreed by Nature on High) -- are still necessary to hold the enterprise together and avoid bankruptcy.
_

 

[axocanth]

I just hate long winded analogies [about baseball], by the time you have explained them, you may as well just have taken the time to talk about the science.
They can be useful if used sparingly.


I will check that out thanks.

He (mainly!) keeps the baseball out of the scientific writings. I don't think you'll find any Babe Ruth talk in his "Punctuated Equilibrium" for example. And if you do, just strike it out.

You have to remember that most of his books are collections of articles that he wrote over the years for newspapers (or something) on a vast array of subjects, not just science, though that figures largely.

Gould is one of these rare people whose breadth of knowledge is quite staggering, leaving you wondering how he possibly had the time to research all that other stuff -- as he does meticulously -- in between revolutionizing evolutionary biology, er I mean, adding ever-so-slightly to The Theory.

You'll find a sophistication in Gould (IMHO) that Dawkins doesn't come close to approaching. Consider for example:

"Facts do not 'speak for themselves'; they are read in the light of theory."

"The new orthodoxy [of plate tectonics] colors our vision of all data; there are no 'pure facts' in our complex world."

- essay "The Validation of Continental Drift", found in "The Richness of Life"

What's Gould telling us here? One does not simply Step 1 : Observe, Step 2 : Form a hypothesis, Step 3: Yawn

Einstein says very similar things. Observation and theory (or just our concepts, if you prefer) are joined at the hip, we don't just observe "neutrally" as it were, reporting the "raw facts".

So what? So when, for example, you view the world through "Theory of Evolution" spectacles, you see everything precisely in accordance with that theory. Everything becomes confirming evidence for that theory. There is no disconfirming evidence for that theory (think Dawkins!). This is something we do without even being conscious of it, and it takes a very rare individual indeed (e.g. Einstein) to remove those spectacles, and view the world another way.

Thomas Kuhn's favorite example was that of the "anomalous playing card". Try it yourself! Insert a black seven of hearts, say, in a regular pack of cards, and I'll betcha you can play bridge for a week without your companions even noticing! There is no disconfirming evidence for the "This is a standard pack of cards" theory.

Oh yeah? Maybe you just weren't looking for any!


By the way, love is like a game of bridge. If you don't have a good partner, you'd better have a good hand.

 

[axocanth]

Think also the fossil record. For a hundred years or more everything dug up was viewed as confirming evidence for gradualism -- even as 10000 snails of a particular species, spanning a period of several million years, were unearthed that all looked exactly alike! (Gould is a snail man)

Now, except for people wearing those gradualist spectacles (i.e. everyone), the obvious conclusion to draw is that evolution is not happening at all. By and large, what the fossil record shows is evolution not happening.

"Stasis", then, just was that anomalous playing card!

 

[axocanth]

And because a main hypothesis may sometimes need support from background assumptions (auxiliary hypotheses), reciprocal tweaks in the latter may allow it to stay in play as a contender, after a test fail. Or again -- like an octopus, maybe it has so many arms prowling in various areas that chopping one off doesn't kill the beast.

Nice way to put it! Of course it's not the way these things are standardly framed: "One pre-Cambrian rabbit and ding-dong the theory is dead".

How a single scrawny pre-Cambrian gavagai contradicts or falsifies "The Theory" is left as another exercise to the reader.


You want a contradiction? How about "No rabbits existed 600 million years ago" vs "This rabbit existed 600 million years ago".

If anyone can find a contradiction between "This rabbit existed 600 million years ago" and, say "All life is descended from a common ancestor" be sure to let the world know.

 

[Yazata]

Is the theory of punctuated equilibrium a gamechanger for evolutionary biology?

My intention in this post is merely to express my initial ideas regarding the subject line, not the rest of the opening post.

First, is punctuated equilibrium really a theory? I'm presently inclined (it could change tomorrow) to think of theories as explanatory contexts that serve to explain and make sense of observations of particular instances. Newton's physics would be a theory in that way, since it allows us to make sense of all kinds of physical observations, turning them into examples of various theoretical Newtonian principles in action.

If 'punctuated equilibrium' is merely jargon for the sudden appearance of species in the fossil record, then it would lack explanatory force. It adds nothing to our understanding to say that the sudden appearance of species in the fossil record is explained by the sudden appearance of species in the fossil record.

But in fairness to those who proposed the idea, I think that it has more content than that. I think that their idea is that species gradually become highly adapted to their ecological niches. Being highly adapted, these populations experience very little selective 'force', we might say, and experience little evolutionary change over long periods of time. They are in a sort of adaptive equilibrium. But if the environment changes, such as Darwin's finches moving to a new island offering different foodstuffs, or perhaps the long-ago transformation of African forest to savannas that's hypothetically forced humanity's ancestors down out of the trees, then selective pressures might suddenly increase, leading to what might later look like a sudden spurt of evolution.

I don't see that as a game-changer, since it's exactly what we would expect on Darwinian principles.

I haven't studied the huge literature on these issues. That said, the biggest game changers to Darwins original ideas that I see might be several fairly recent and interrelated developments:

1. The discovery of horizontal gene transfer in prokaryotes. Bacteria and archaea don't acquire all of their genes from their ancestral cells, they way we acquire our genes from our parents. Bacteria and archaea acquire some of their genes from their neighbors, in the form of plasmids that are passed back and forth. Which makes microbial taxonomy very difficult and different than taxonomy in higher organisms. That will have obvious implications for our understandings of microbial evolution which while natural selection definitely takes place, isn't exactly Darwinian.

https://en.wikipedia.org/wiki/Horizontal_gene_transfer

2. The broader discovery of molecular genetics, DNA, the genetic code and the incredibly complex regulatory mechanisms that control which genes are expressed when and for how long. Darwin knew nothing of this and these discoveries have dramatically expanded evolutionary theory far past where it was in the 19th century. That's definitely the biggest game-changer in the history of evolutionary theorizing. That brings us to mutations and what exactly is mutating when mutations occur. (There is more than one kind of mutation, SNPs and gene duplications for instance, with different evolutionary impacts.) How rapid is the rate of mutation at the genomic level and is the rate constant across the whole genome? The answer to that last question is 'no'. There are are some genes and larger sets of genes that are highly conserved across whole lineages and sometimes all animals. An example of that are the famous HOX genes that are found in all animals since the time of the Cambrian explosion and which determine the anterior-posterior axis in very early fetal development. HOX genes are why animals have heads at the anterior end. Other HOX genes determine where on the body arms, legs, wings or antennae sprout. Why are these genes highly conserved through the history of life? Because if they are lost or altered, vital parts of fetal development would fail, so there is huge selective pressure against passing these profound defects on to offspring. Fetuses with these defects are usually spontaneously aborted.

Hox gene - Wikipedia

en.wikipedia.org

3. Which brings us to what I take to be a third game-changer - evolutionary developmental biology. If our genes and their regulatory systems are most active in fetal development, and if mutations in some of them result in much more profound impacts than others (lack of a head compared to a slightly more pointed bird beak), we would expect more and less dramatic phenotypical changes depending on where in the developmental process a mutation occurs. So even if the rate of mutation in the genome is relatively constant, based on the underlying chemistry of nucleic acids, we might see more or less dramatic phenotypic variants appearing over time quite suddenly (the 'punctuations' of the equilibrium) depending on where in the developmental process a mutation occurs. If a species is already highly adapted to its ecological niche (the 'equilibrium') then all the larger and more dramatic 'macroevolutionary' variants and most of the smaller 'microevolutionary' variants as well, will put an organism at a selective disadvantage. But occasionally (usually when ecology is changing) a greater or lesser variation will confer selective advantage. And a new "species" will seem to pop into the fossil record all at once.

Evolutionary developmental biology - Wikipedia

en.wikipedia.org

Or something like that. I'm just thinking out loud here.

 

[axocanth]

Hi Yazata. Glad to have you with us!

If 'punctuated equilibrium' is merely jargon for the sudden appearance of species in the fossil record, then it would lack explanatory force. It adds nothing to our understanding to say that the sudden appearance of species in the fossil record is explained by the sudden appearance of species in the fossil record.

I'm just repeating what has already been said earlier (see especially post #1), but here goes, and assuming I've got all this right myself . . .

In the early 1970s, PE was advanced as a theory (or whatever you want to call it) about the pattern of evolution. Its contention was that what Gould & Co, named phyletic gradualism is wrong. The fossil record typically (this contention is to be judged on relative frequency; not an absolute dichotomy) does not show the kind of gradual change that traditional Darwinian theory would lead us to expect. Quite the contrary, what typically is seen is a species entering the fossil record abruptly and mysteriously, changing little or not at all for a few million years, then disappearing equally mysteriously. I say "mysteriously" because transitional forms linking them to other species are almost entirely absent from the record. This of course is only mysterious if one is already committed to a theory of gradual change.

The PE crowd had an explanation for this pattern too, but it was not new. As you go on to describe yourself, this peculiar record is explained by allopatric speciation, that is, isolated peripheral groups branching off from the main groups. Note, this is a form of cladogenetic evolution -- a splitting of one into two -- as opposed to the more traditional anagenetic evolution of change within the same population, exemplified in (highly misleading!) museums and textbooks everywhere (proto-horse to modern horse kind of thing, not to mention peppered moths).

But in fairness to those who proposed the idea, I think that it has more content than that. I think that their idea is that species gradually become highly adapted to their ecological niches. Being highly adapted, these populations experience very little selective 'force', we might say, and experience little evolutionary change over long periods of time. They are in a sort of adaptive equilibrium. But if the environment changes, such as Darwin's finches moving to a new island offering different foodstuffs, or perhaps the long-ago transformation of African forest to savannas that's hypothetically forced humanity's ancestors down out of the trees, then selective pressures might suddenly increase, leading to what might later look like a sudden spurt of evolution.

I don't see that as a game-changer, since it's exactly what we would expect on Darwinian principles.

Yes, you're right, it does have more content than that -- although it is routinely mischaracterized as asserting nothing more than what I've just sketched above, much to the chagrin of the exponents!

Also as explained in the OP, the theory was soon expanded. The extended stasis of species in the fossil record led to the realization that species are actually stable, well-defined entities (think of a tornado, say), unlike the "arbitrary sections of a continuum" as they had so often been characterized previously by people like Darwin himself. Species, then, are both real and -- this is the tricky part to get your head around -- they are individuals.

What does that mean? It means we should not think of a species -- zebra, say -- as like a set consisting of members (i.e. each individual animal), but as an individual whole consisting of parts (i.e. each individual animal). The species zebra, then, is itself an individual consisting of individual organisms as its parts.

What's so radical about that? Well, if you're a real individual (e.g. the species zebra) then you can be selected, analogously to individual organisms (i.e. each particular animal) being selected in traditional theory. This now opens up a vast new domain of research: macroevolution. A "decoupling" or "uncoupling" occurs. Whereas previously it was believed that microevolutionary forces (think of peppered moths) could be extrapolated to explain all evolution -- it's just more of the same; one reduces to the other; there is no qualitative difference -- it is now proposed that macroevolution must be understood on its own terms.

Now, among other implications, this implies that you're not going to understand the larger patterns in evolution by playing around with fruit flies in the lab, as population geneticists ( Can you name one whose initials are RD?) are wont to do. It's not hard to see, then, why population geneticists were not overly enamored by the new kid on the block.



Oops, I gotta run now. I want to comment on this more later. I picked up Gould's "Punctuated Equilibrium" from the library again as I thought it might come in handy. In the final section Gould bemoans frequent mischaracterizations of PE ideas and divides them into two kinds: (i) innocent misunderstandings -- people who simply have not familiarized themselves with the primary material, and (ii) the nasty kinds (I'll say no names lol).


The first kind sounds an awful lot like what exchemist has been saying in recent posts -- roughly "Nothing new. Yawn!"



Back later . . .

 

[axocanth]

P.S. Gould does say that transitional forms linking species to species are extremely rare in the fossil record. So do other paleontologists. This has often been distorted by Creationists as there are no transitional forms at all.

Overzealous defenders of The Theory (e.g. the Youtube gods) often distort matters just as badly though. They, in their confusion, react by saying every fossil is transitional.

If every fossil is transitional, why they create such a fuss when discovered is left to the reader to ponder.

 

[axocanth]

More on Yazata's interesting post later (time permitting), but for now take a quick look again at what I wrote in post #60 . . .

If I remember correctly, what originally brought us to where we are today -- besides delicious serendipity -- was the claim that macroevolution reduces to microevolution.

The PE crowd claims it does not. (The evo-devo people too), TheVat posted a link to another commentator who feels that cases of irreducible macroevolutionary process are rare but nonetheless real.

Perhaps the significance has not sunk in yet. If these guys are right then, rare or not, the reduction fails. It's the same effect that a measly single black swan has on the assertion "All swans are white" - i.e. catastrophic!

A similar thing happens in the philosophy of mind with attempts to reduce the mental to the physical. If something is left out (e.g. qualia) in this putative reduction, then the reduction fails, physicalism is wrong, and it's the end of the world.

Pinball, have you got a hold of Gould's "Punctuated Equilibrium" yet? In what follows, I'll be drawing from and quoting from pages 329 -331 (some sentences omitted for brevity).

Gould tells us first that of all his papers on PE, the one that caused the greatest uproar was his 1980 "Is a new and general theory of evolution emerging?" (cf. "Is the Theory of Punctuated Equilibrium a Game Changer?")

Now, with a title like that a few cages are bound to get rattled, and they were . . .

(When Gould speaks of a general proposition, think "All swans are white". Read "transspecific evolution" as "macroevolution". All emphasis in original.)

The received legend about this paper -- I really do wonder how many colleagues have ever based their comments on reading this article with any care, or even at all -- holds that I wrote a propagandistic screed featuring two outrageously exaggerated claims: first, the impending death of the Modern Synthesis; and second, the identification of punctuated equilibrium as the exterminating angel (or devil).

[ . . . ]

Given the furor provoked, I would probably tone down -- but not change in content -- the quotation that has come to haunt me in continual miscitation and misunderstanding by critics: "I have been reluctant to admit it -- since beguiling is often forever -- but if Mayr's characterization of the synthetic theory is accurate, then that theory, as a general proposition, is effectively dead, despite its persistence in textbook orthodoxy. (I guess I should have written the blander and more conventional "due for a major reassessment" or "now subject to critical scrutiny and revision" rather than "effectively dead.")

Yes, the rhetoric was too strong (if only because I should have anticipated the emotional reaction that would then preclude careful reading of what I actually said). But I will defend the content of the quotation as just and accurate. First of all, I do not claim that the synthetic theory of evolution is wrong, or headed for complete oblivion on the ashheap of history; rather, I contend that the synthesis can no longer assert full sufficiency to explain evolution at all scales (remember that my paper was published in a paleo-biological journal dedicated to studies of macroevolution). Two statements in the quotation should make this limitation clear. First of all, I advanced this opinion only with respect to a particular, but (I thought) quite authoritative, definition of the synthesis: "if Mayr's characterization of the synthetic theory is accurate." Moreover, I had quoted Mayr's definition just two paragraphs earlier. The definition begins Mayr's chapter on "species and trans-specific evolution" from his 1963 classic -- the definition that paleobiologists would accept as most applicable to their concerns. Mayr wrote (as I explicitly quoted): "The proponents of the synthetic theory maintain that all evolution is due to the accumulation of small genetic changes, guided by natural selection, and that transspecific evolution is nothing but an extrapolation and magnification of the events that take place within populations and species."

Second, I talked about the theory being dead "as a general proposition," not dead period. In the full context of my commentary on Mayr's definition, and my qualification about death as a full generality, what is wrong with my statement? I did not proclaim the death of Darwinism [note terminology! - axo], or even of the strictest form of the Modern Synthesis. I stated for an audience interested in macroevolutionary theory, that Mayr's definition (not the extreme statement of a marginal figure, but an explicit characterization by the world's greatest expert in his most famous book) --with its two restrictive claims for (1) "all evolution" due to natural selection of small genetic changes, and (2) transspecific evolution as "nothing but" the extrapolation of microevolutionary events -- must be firmly rejected if macroevolutionary theory merits any independent status, or features any phenomenology requiring causal explanation in its own domain. If we embrace Mayr's definition, then the synthesis is "effectively dead" "as a general proposition" -- that is, as a theory capable of providing a full and exclusive explanation of macroevolutionary phenomena. Wouldn't most evolutionary biologists agree with my statement today?

Nonetheless, I was reviled in many quarters, and in prose far more intemperate and personal than anything I ever wrote, for proclaiming the death of Darwinism, and the forthcoming enshrinement of my own theory as a replacement.

In conclusion, then, if one black swan sounds the death knell for the general proposition "All swans are white" then a single case of irreducible macroevolutionary processes sounds the death knell for the Modern Synthesis as described by Ernst Mayr as a general proposition. Simple logic compels us to assign a value of false to both.

There's nothing to stop you from shrugging your shoulders, though, and announcing that some or even most swans are white, although this will require empirical confirmation, of course.

But note what has happened. You have withdrawn an earlier claim, conceded its falsity, and proposed a new claim in its place. This is no extension of the original claim.

 

[Pinball1970]

Pinball, have you got a hold of Gould's "Punctuated Equilibrium" yet? In what follows, I'll be drawing from and quoting from pages 329 -331 (some sentences omitted for brevity).

I had look in Waterstones Saturday but I need to go to the library.

 

[axocanth]

My intention in this post is merely to express my initial ideas regarding the subject line, not the rest of the opening post.

First, is punctuated equilibrium really a theory? I'm presently inclined (it could change tomorrow) to think of theories as explanatory contexts that serve to explain and make sense of observations of particular instances. Newton's physics would be a theory in that way, since it allows us to make sense of all kinds of physical observations, turning them into examples of various theoretical Newtonian principles in action.

As you're defining the term theory (i.e. something explanatory) then I'd agree PE counts as a theory. It not only describes and predicts what is seen, but tells us why this is so.

My own view on this is that it doesn't matter a jot what we call these things; what matters is whether they're saying anything worthy of attention. Of course many textbooks and science educators these days do offer a very specific definition of the term "theory" in science -- totally different from its vernacular usage, we are told -- and it does not correspond to the way actual scientists use the term! I have another thread on that very topic ("The Stage Theory of Theories").

But in fairness to those who proposed the idea, I think that it has more content than that. I think that their idea is that species gradually become highly adapted to their ecological niches. Being highly adapted, these populations experience very little selective 'force', we might say, and experience little evolutionary change over long periods of time. They are in a sort of adaptive equilibrium. But if the environment changes, such as Darwin's finches moving to a new island offering different foodstuffs, or perhaps the long-ago transformation of African forest to savannas that's hypothetically forced humanity's ancestors down out of the trees, then selective pressures might suddenly increase, leading to what might later look like a sudden spurt of evolution.

I'm glad you raised this because I'm stuck for an answer! The PE view is quite clear that stasis is the norm, though why this is so . . . um, I'll be re-reading Gould's "Punctuated Equilibrium" soon, let you know what I find, and whether it tallies with what you say above.

I don't see that as a game-changer, since it's exactly what we would expect on Darwinian principles.

Again this gets tricky because it's hard to know what precisely these Darwinian principles are. And as I've learned from experience, you can show pretty much anything you like to the unflappable Darwinian -- fast change, slow change, no change at all for a hundred million years -- and they don't bat an eyelid, "That's perfectly consistent with The Theory."

Consistent perhaps (after all any observation is consistent with a typical scientific theory, as I pointed out somewhere else recently), but how about expected?

There are passages in Darwin, for example, where he's explicit that the struggle for existence is constant and ruthless, natural selection ceaselessly casting her eye over nature, and so on. Now, if that's a tenet of The Theory then surely we'd expect to see more or less gradual steady constant evolutionary change, and that's what people before PE did expect to see. The reason the fossil record was blamed for being "incomplete" is precisely because it did not reflect what the theory would lead us to expect.

Now, if on the other hand, you have a theory that says evolutionary episodes are relatively rare, species tend to be stable throughout their existence, then the fossil record is in accordance with our theoretical expectations. There is no longer any need to blame the fossil record.

 

[axocanth]

Oh, one more thing, Yazata. Yes, both PE and evo-devo challenge the traditional view that macroevolution is nothing but microevolution writ large. But for different reasons.

The evo-devo people invoke macromutations, as included in your post, that is, radical change in a single generation.

The PE people, on the other hand, make no mention of macromutations, at least that I've seen, indeed they get peeved when their views are conflated with Auric Goldfinger's "hopeful monsters". The reason they reject the reduction of macroevolution to microevolution is, as already discussed, they believe it's not just traditional Darwinian selection acting on individual organism "all the way up." Species are selected too.

Assuming I've got this right again.

 

[axocanth]

I'm glad you [Yazata] raised this because I'm stuck for an answer! The PE view is quite clear that stasis is the norm, though why this is so . . . um, I'll be re-reading Gould's "Punctuated Equilibrium" soon, let you know what I find, and whether it tallies with what you say above.

Proposed causes of stasis are found pp175-185. I'll get back to you!

Note the echoes of a familiar Creationist objection, and not just Creationists (early opponents of Darwin levelled the same objection):

"As any breeder knows, do whatever you like with pigeons or dogs or horses, do it for as long as you like, you'll see some (microevolutionary) change, but they stay pigeons, dogs, and horses."

 

[axocanth]

Theoretical constructs that cover or help explain a broad variety of things obviously aren't going to be abandoned or significantly disparaged in importance because of one of their predictions (or whatever) being falsified in one of those particular nooks. And some continue to be invaluable tools, like Newton's innovations not becoming obsolete.

Yes indeed! And this can be the source of all kinds of confusions.

For example, suppose Smith claims that classical Newtonian physics was overthrown (or similar locution) by relativistic physics. It's a sensible enough claim, and Smith would have no difficulty at all locating leading physicists who say exactly the same thing.

Jones, meanwhile, rejects Smith's claim. It was not overthrown. It's still taught and scientists still use it to send people into space. Another sensible claim, and Jones would likewise have no trouble finding support for it.

Can they both be right? Obviously not! Something cannot be both overthrown and not overthrown.

Ah, but what if they don't mean the same thing by "overthrown"?

In an epistemological sense, if one asserts the truth of relativist physics then -- on pain of inconsistency -- one must assert the falsity of Newtonian mechanics. To nail your epistemological colors to one is to say that the other has been overthrown. They cannot both be true. "Overthrown" = no longer believed.

In an instrumental sense, by contrast, the purchasing of a new electric drill no more overthrows your old hand drill than Einstein does Newton, indeed the old drill might even be more useful for certain applications, e.g. drilling a hole when Louise is sleeping and you don't want to wake her up. Awwww!.

 

[TheVat]

In an epistemological sense, if one asserts the truth of relativist physics then -- on pain of inconsistency -- one must assert the falsity of Newtonian mechanics. To nail your epistemological colors to one is to say that the other has been overthrown. They cannot both be true. "Overthrown" = no longer believed.

In an instrumental sense, by contrast, the purchasing of a new electric drill no more overthrows your old hand drill than Einstein does Newton, indeed the old drill might even be more useful for certain applications, e.g. drilling a hole when Louise is sleeping and you don't want to wake her up. Awwww!.

Never been sure if there is any sense in which GR "overthrows" Newtonian. Certainly the instrumentalist view is that it's an upgrade to handle high velocities and large masses and so on. But are there really any epistemologists out there who would have such a narrow definition of truth that they couldn't acknowledge that GR is more a patch than a contradiction? In your Smith and Jones contention, I would say Smith is probably just wrong and should concede Jones's point. Overthrown, after all, isn't all that ambiguous in its meaning - it sorta means tossed in the wastebasket, no longer of use. Overthrown dictators don't hang around the palace dispensing helpful nuggets of wisdom. But that clearly isn't the case with Newtonian fizz.

Similarly, punk eek seems to also work as an upgrade. Corrects some of the timetables, expands the selection concept from individual phenotypes to the character of the species as a whole, points out acceleration effects of a rapid ecological change, makes sense of the rapid adaptation of bacteria sharing plasmids, provides a useful framework for cladogenesis, etc. Not to be all harmonic convergence and singing Kumbaya together, but the conceptual expansion from micro to macroevolution just seems like a natural development and not one where people have to get upset about holistic species-level effects as some sort of theoretical coup. It's a bit like cognitive science where signals exchanged between neurons can provide some explanatory basics while acknowledging other functional levels with holistic brain processes like intention, meaning, and the unflagging love of Louisa May AllCat. (her official moniker)