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Sunday, December 04, 2016

Kevin Laland's new view of evolution

The recent meeting at the Royal Society in London was organized by The Royal Society (UK) and The British Academy. The theme of the meeting was, "New trends in evolutionary biology: biological, philosophical and social science perspectives." The main organizers were Denis Noble, Nancy Cartwright, Patrick Bateson, John Dupré, and Kevin Laland. The point of the meeting was to discuss new evolutionary theory.

It's difficult to describe everything that went on at the meeting because so much of it was details about individual research results. These scientific talks were often presented as an alternative to modern ways of thinking about evolution. The general theme was that the Modern Synthesis was out-of-date and needed revision or, perhaps, replacement. There was very little discussion of evolutionary theory and how best to interpret those results. The data was supposed to speak for itself.

The only serious objections came from scientists who claimed the Modern Synthesis had already incorporated the ideas of niche construction, plasticity, epigenetics etc. This message was promoted mainly by Douglas Futuyma and Russell Lande. They weren't very successful.

I think that was the wrong message. I think the Modern Synthesis is effectively dead. It died 45 years ago when the importance of non-Darwinian evolution became evident. I'm certain the vast majority of participants were completely ignorant of molecular evolution and random genetic drift. They missed the revolution [see Is the "Modern Synthesis" effectively dead?].

Here's a quotation from Douglas Futuyma's textbook Evolution (2nd edition, 2009).
Since the evolutionary synthesis, a great deal of research has elaborated and tested its basic principles, and these principles have withstood the tests. But progress in both evolutionary studies in other fields of biology has required some modifications and many extensions of the basic principles of the evolutionary synthesis, and has spurred additional theory to account for biological phenomena that were unknown in the 1940s....

As molecular and computational technology has become more sophisticated and available, new fields of evolutionary study have developed. Among these fields is molecular evolution (analysis of the process and history of change in genes), in which the Neutral Theory of Molecular Evolution has been particularly important. This hypothesis, developed especially by Mootoo Kimura (1924-1994), holds that most of the evolution of DNA sequences occurs by genetic drift rather than by natural selection, but it provides a foundation for detecting effects of natural selection on DNA sequences. Because entire genomes can now be sequenced, molecular evolutionary studies have expanded into evolutionary genomics, which is concerned with variation and evolution in multiple genes or even entire genomes.
Let's look at an article by Kevin Laland published in New Scientist at the end of September (2016). It was obviously intended to publicize the meeting.

Laland is a professor at the University of St. Andrews in Scotland (UK). His main research interest is the evolution of human behavior and he promoted the importance of niche construction at the meeting. The New Scientist article was published as part of a series on "Evolution: Selfish genes aren't in control after all. Organisms help direct their own evolution."

Laland's article is "Evolution Evolves: Darwin's and Wallace's brainchild is still spawning radical ideas. Kevin Laland describes a vision of evolution for the 21st century." The online title is: Evolution evolves: Beyond the selfish gene For more than 150 years it has been one of science’s most successful theories, but we need to rethink evolution for the 21st century.

The article begins by explaining that "Darwin’s beautiful idea explains why there are hundreds of thousands of species of beetles and flowering plants, why birds’ feathers are ideal for flight and insulation, and why a desert plant possesses hairy leaves to reduce water loss."

That's only partly true. The Theory of Natural Selection (Darwin's beautiful idea) may explain feathers and hairy leaves but it certainly does not explain diversity. That's the first problem.

As we look more closely at Laland's ideas we actually see two problems. The first is that he is attacking a strawman version of evolutionary theory—one that's extremely adaptationist. The second problem is thinking that Dawkins' view of the selfish gene is the dominant metaphor in modern evolutionary theory. We see this second strawman in statements like,
Yet all scientific theories must incorporate new ideas and findings, and evolution is no exception. In recent years, our understanding of biology has taken huge strides. Advances in genetics, epigenetics and developmental biology challenge us to think anew about the relationship between genes, organisms and the environment, with implications for the origins of diversity and the direction and speed of evolution. In particular, new findings undermine the idea, encapsulated by the “selfish gene” metaphor, that genes are in the driving seat. Instead, they suggest that organisms play active, constructive roles in their own development and that of their descendants, so that they impose direction on evolution.
I was surprised to discover in London that none of these "revolutionaries" could define "evolution" in any meaningful way. They give me the impression they are unsatisfied with "changes in allele frequencies in a population" but they have no reasonable alternative.1 If niche construction just affects changes in allele frequencies then what's the fuss all about? Lots of things influence genetic changes in populations.

But let's concentrate on the first strawman that Leland is tilting at. He says,
Our current framework for thinking about evolution emerged only in the 1940s, with the integration of new knowledge about evolutionary processes and biological inheritance. This so-called modern synthesis is at the heart of how most people understand evolution. According to this view, the evolution of the features of an organism – collectively known as its phenotype – comes down to random genetic mutation, genetic inheritance and selection of those gene variants that bestow traits best adapted to the environment.

The modern synthesis has served us well: evolutionary biology is developing and thriving. But discoveries made over the past two decades are starting to reveal cracks in some of its central ideas.
Really? The "current framework" dates back to the 1940s and only considers selection? The only challenge to this view comes from discoveries that began in 1996?

This is the problem. Somewhere between the 1940s and 1996 there must have been a few advances in knowledge about evolutionary theory, right? (cough, King and Jukes, 1969).

Now it's one thing to consider non-Darwinian evolution and all the new ideas that were promoted in the 1960s, 1970s, and 1980s and then reject them in favor of the old-fashioned view of the adaptationist Modern Synthesis. I can respect that even though I think it's indefensible. But it's quite another thing altogether to be completely ignorant of all those ideas while advocating a revolution in 2016!

That's what Kevin Laland is doing and so are most of the other participants at the Royal Society meeting.

We can see it clearly because in Laland's article he gives us a nice summary of the "Modern vs Postmodern" views of evolution. Judge for yourself whether you think this is someone who's an expect on modern evolutionary theory.
Modern vs postmodern
Orthodox ideas about how evolution works are being challenged by new discoveries in genetics, epigenetics and developmental biology. This has led some researchers to propose that the current framework, known as the modern synthesis, be broadened into an extended evolutionary synthesis. The fundamentals remain the same, but they rest on quite different assumptions:

Modern synthesis
The major directing influence in evolution is natural selection. It alone explains why the properties of organisms are adapted to match those of their environments.

Extended evolutionary synthesis
Natural selection is not solely in charge. The way that an organism develops can influence the direction and rate of its own evolution and its fit to its environment.
The problem here is that Laland is not wrong about the Modern Synthesis. He's just wrong about the fact it represents the modern view of evolution. As Douglas Futuyma pointed out at the meeting, all modern textbooks have chapters on random genetic drift and plenty of discussion about nonadaptive evolution, especially at the molecular level. It makes you wonder whether the biologists at the Royal Society meeting ever read a modern textbook on evolution.

That's the part that really bothers me about this debate. However, let's pretend that Laland actually understood modern evolutionary theory. Does it make any sense to propose that it needs rethinking in light of the fact that organisms affect the environment they live in? No.
Modern synthesis
Genes are the only widespread system of inheritance. Acquired characters – non-genetic traits that develop during an organism’s lifetime – are not inherited and play no role in evolution.

Extended evolutionary synthesis
Inheritance extends beyond genes to include epigenetic, ecological, behavioural and cultural inheritance. Acquired characters can be passed to offspring and play diverse roles in evolution.
He's correct here about the Modern Synthesis and about modern evolutionary theory. The modern view does not recognize that changes in the frequency of non-genetic characteristics of a population over time counts as biological evolution.

Epigenetics, which has been around for 50 years, is not a major new player in evolution. To the extent that it's important, it's genetic. Cultural and behavioral evolution are real phenomena but they're not biological evolution.2
Modern synthesis
Genetic variation is random. Mutations that occur are not necessarily fitness-enhancing. It is mere chance if mutations give rise to features that improve the ability of organisms to survive and thrive.

Extended evolutionary synthesis
Phenotypic variation is non-random. Individuals develop in response to local conditions, so any novel features they possess are often well suited to their environment.
Almost all evolution is ultimately due to mutation of one sort or another. Many people believe that the chance occurrence of mutation is the dominant theme of evolution. The statement about the Modern Synthesis is perfectly correct, to a first approximation. (We can quibble about details.)

The idea that phenotypes change according to local conditions—for example, the lac operon is expressed in the presence of lactose—is hardly revolutionary and doesn't require a change in our understanding of modern evolutionary theory.
Modern synthesis
Evolution typically occurs through multiple small steps, leading to gradual change. That’s because it rests on incremental changes brought about by random mutations.

Extended evolutionary synthesis
Evolution can be rapid. Developmental processes allow individuals to respond to environmental challenges, or to mutations, with coordinated changes in suites of traits.
Is it possible that Kevin Laland is completely unaware of the debate over gradualism, hybridization, symbiosis, horizontal gene transfer, homeotic mutations, saltation, and macromutations? Is it possible that he's never thought about punctuated equilibria, and hierarchical theory?

It's true that the old-fashioned views of Ernst Mayr and company ("Modern Synthesis") rejected all those ideas but evolution has moved on since the 1950s. It's no longer restricted to just gradual small steps.

The "revolutionaries" think mutations can be directed with an ultimate goal in view. The basic idea of enhanced mutation rates under certain conditions has been actively debated for a very long time (before 1996). It's not thought to be a major feature of evolution except in the sense of increasing the rate of "random" mutations.
Modern synthesis
The perspective is gene-centred: evolution requires changes in gene frequencies through natural selection, mutation, migration and random losses of gene variants.

Extended evolutionary synthesis
The view is organism-centred, with broader conceptions of evolutionary processes. Individuals adjust to their environment as they develop, and modify selection pressures.
This description of the Modern Synthesis is the only time I've seen Kevin Laland mention something that resembles random genetic drift. It's clearly not part of his normal worldview.

I agree that modern evolutionary theory is "gene-centered" in this way. That's because we DEFINE evolution as a change in allele frequencies in a population. I don't know what it means to shift to a view that's "organism-centered" in the way Laland describes. It's certainly true that individual cyanobacteria adjust to their environment as they grow and develop and it's certainly true they can change the environment. In this case, they caused an increase in oxygen levels that affected all living species.

Cyanobacteria evolved to adjust to their environment by random mutations and changes in allele frequencies in the population due, in part, to selection. Many became extinct. How is that a change in our view of evolution?
Modern synthesis
Micro-evolutionary processes explain macro-evolutionary patterns. The forces that shape individuals and populations also explain major evolutionary changes at the species level and above.

Extended evolutionary synthesis
Additional phenomena explain macro-evolutionary changes by increasing evolvability – the ability to generate adaptive diversity. They include developmental plasticity and niche construction.
It was a basic tenet of the Modern Synthesis that macroevolution can be efficiently explained as just lots and lots of cumulative microevolution. Modern evolutionary biology textbooks discuss other features of macroevolution that require additional input, especially in speciation. The old idea that microevolution is sufficient to account for macroevolution is no longer the axiom in evolutionary biology and hasn't been for many decades [see Macroevolution].

Modern textbooks discuss all kinds of things that influence the long-term history of life (= macroevolution). Things like mass extinctions, stasis, allopatric speciation, constraints, etc. Evolvability has been actively debated for half-a-century and it's well-covered in most textbooks. (See Futuyma, 2nd ed. p. 599). Evolvability is hardly a new idea that's going to revolutionize evolutionary theory. In fact, the consensus view, after much debate and discussion, is that evolvability flounders on the shoals of teleology. The theory just doesn't hold up to close scrutiny.
Organismal selection for traits that confer differential reproductive success in the ecological moment simply cannot generate, in any active or direct manner, a set of features that achieves evolutionary significance only by imparting flexibility for change in the distant future. We cannot deny that these features of evolvability deeply "matter" in the history of lineages; but how can benefits for futures arise by any causal process in the here and now? (Gould, 2002 p. 1274)
It's disingenuous to imply, in an article intended for the average reader, that a subject like evolvability is recent and hasn't been thoroughly vetted, and rejected, in the theoretical literature on evolution. The same thing applies to the concepts of plasticity and niche construction. They aren't new concepts. The knowledgeable experts in evolution—the ones who have read, and written, the textbooks—have examined these ideas and rejected them as major factors in evolutionary theory.

Kevin Laland may disagree with those analyses but as a scientist he has an obligation to at least mention them when he writes articles promoting a radical change in evolutionary theory. He has a responsibility to declare his bias.

But I'm making an assumption that may not be warranted. Maybe he doesn't know that his views have already been debated, discussed, and, for the most part, rejected. In that case, his omission isn't because he's deliberately misleading his readers about the controversy. There's another reason.

1. The focus on heritable change (alleles) is part of the current minimal definition of evolution. It's very different than the "selfish gene" perspective promoted by Richard Dawkins. Those who fail to see the difference are just not paying attention.

2. I wonder how "cultural evolution" works in cyanobacteria and maple trees? The major participants at the Royal Society meeting have an extreme bias toward evolution of complex multicellular organisms—mostly animals and mostly mammals. This greatly colors their perspective on evolution. They tend to uses examples that apply only to their species of interest as levers to tip over all of evolutionary theory.

King, J. L., and Jukes, T. H. (1969) Non-darwinian evolution. Science, 164:788-798. PDF


Donald Forsdyke said...



"It's disingenuous to imply, in an article intended for the average reader, that a subject like evolvability is recent and hasn't been thoroughly vetted, and rejected, in the theoretical literature on evolution."

True, it is not "recent." The concept of evolvability, although he did not use that word, was introduced at least as early as 1867 by Fleeming Jenkin. But there is much to commend it today.

Mikkel Rumraket Rasmussen said...

Ironically by making it "organism centered", Laland seems to be skipping genetics and going straight to phenotype thus effectively advocating the view of evolution proposed by Darwin himself, who pretty much left out the mechanism responsible for inheritance because he didn't know about it. We've come full circle, Neo-Darwinism is dead. Hail original Darwinism!

Gregory said...

"I was surprised to discover in London that none of these 'revolutionaries' could define 'evolution' in any meaningful way." - Larry

That doesn't surprise me at all, especially since "philosophical and social science perspectives" were also in the program. When such terms as 'selfish' and 'random' are being misused, there are bound to be problems.

Unless one is proposing a 'universal evolutionism' that is simply acid thrown haplessly over everything, no one seems to have the best 'lines on the map' drawn right now. Few people trust Dawkins anymore and there's no new leader of the Evolutionariat to 'eXtend eVolution' to the furthest reaches of the universe.

For example, are you speaking only about biological evolution? If so, that's fine for a restricted disciplinary conversation alone, but it's not what the Royal Society event drew up with philosophy and social science weighing in. In the N. American context they are usually absent, not so the further east one goes to the Eurasian Continent.

"Cultural and behavioral evolution are real phenomena but they're not biological evolution." - Larry

With the conclusion I agree; "they're not biological evolution". Yet a strong argument is available that 'cultural evolution' is itself a self-referentially confused misnomer and 'behavioural' is either outdated with behaviorism or not of the "philosophy and social science" interest above the zoological level.

One of the problematics at the Royal Society meeting and even simply that the prospect of an EES reveals, is that non-biological (or even, non-naturalistic?) disciplines are not just going to back down as biologists try to 'extend' their biological results and analyses into other disciplinary territories, and certainly not easily (with the haunting memory of sociobiology still so raw and abrasive) into human society.

"Inheritance extends beyond genes to include epigenetic, ecological, behavioural and cultural inheritance." - Laland

This seems to be the only concrete example of what 'extension' is supposed to mean in Laland's article. Sooner or later epigenetics takes us out of biology into ecology, then ... into culturology?

It's a kind of reverse impingement; either evolutionary externalism or 'internalist' extended phenotype into (memetics) cultural evolutionary fuzz. Quite a dilemma!

Anonymous said...

"I think the Modern Synthesis is effectively dead. It died 45 years ago when the importance of non-Darwinian evolution became evident."

So, the problem isn't so much that we don't need a new name for current evolutionary theory, but that we've needed it for decades?

Jass said...

Hey Professor Moran!
I hope you are well...
I'm very glad that you finally have decided to report on the RSM. I was looking forward to your own prospective on it and I hope for more. Please do not leave us all out of the loop!


Gregory said...

Perhaps it is the double usage of 'modern' that gets in the way as communicative confusion. 'Modern Synthesis' and 'modern evolutionary theory' don't seem to signify the same according to Larry. Please correct if that's wrong.

Sometimes 'modern' is just meant to signify 'current' or 'contemporary' at other times it means 'recent' or 'latest', etc. and not usually 'from the modern (i.e. older) era' than nowadays. Iow, to say the 'Modern Synthesis is effectively dead" means it is not *current*, but rather outdated.

Otherwise, I agree, there would need to a new name, whether 45 years ago or now matters not. So, what's the name (beyond mere 'extension')?

Tim Tyler said...

Regarding: "Cultural and behavioral evolution are real phenomena but they're not biological evolution."

They are according to the proponents in these fields. Presumably you agree that they are biological (by definition, biology is the science of life) - but don't think they count as evolution. That's down to your definition of evolution. You have given your preferred definition as follows: "Evolution is a process that results in heritable changes in a population spread over many generations". The most significant problem here is encapsulated in the word "heritable". That word might exclude cultural variation by definition. You should consider using the word, "inherited" instead - to avoid bias in your definition against non-genetic forms of inheritance. If you do that, cultural evolution fits within the remit of your definition. Almost everyone agrees that cultural information can be inherited across multiple generations. Suddenly you will find that you can start to make sense of the blooming literature on Darwinan cultural evolution.

Even with your original definition, meme-gene coevolution is a thing. So, cultural evolution influences the frequencies of DNA genes. Since cultural evolution has such short generation times it can happen rapidly. So, the dynamics of meme-gene coevolution often consist of cultural evolution dragging genetic evolution along behind. So you ought to be able to at least agree that cultural evolution influences the genetic evolution of humans and other cultural creatures.

Tim Tyler said...

Re: "We've come full circle, Neo-Darwinism is dead. Hail original Darwinism!"

That's exactly right. The modern synthesis of the 1940s tied evolution to DNA genes and excluded cultural evolution, contrary to Darwin's explicit embrace of the evolution of languages and customs. Darwin (1871) wrote: "The survival or preservation of certain favored words in the struggle for existence is natural selection." Neo-Darwinism was a backwards step from his perspective. Many cultural evolution enthusiasts recognize this explicitly. For example, Alex Mesoudi (2015) writes:

"Cultural evolution is the theory that this socially transmitted information evolves in the manner laid out by Darwin in The Origin of Species, i.e. it comprises a system of variation, differential fitness and inheritance. Cultural evolution is not, however, neo-Darwinian, in that many of the details of genetic evolution may not apply, such as particulate inheritance and random mutation."

Tim Tyler said...

Your Gould quotation is surely wrong about evolvability. Evolvability is basically why we have so few long-lived asexual lineages. This example illustrates where Gould's argument comes unstuck. Evolvability isn't a consequence of teleology in biology. Gould asks: "how can benefits for futures arise by any causal process in the here and now?" The answer is perfectly pedestrian: the future is often like the past and so things that were beneficial in the past are often also beneficial in the future. Evolving fast helps lineages to outrun rapidly evolving parasites and helps to adapt to changing environments - and indeed non-uniform environments. You even suggest that there's a consensus that evolvability has been rejected due to problems with teleology. I don't think that's right. There's some remaining debate about whether evolvability is an adaptation or a byproduct of other adaptive forces, but that seems a bit different to questioning its significance.

Tim Tyler said...

I am not clear about where the idea that Kevin Laland doesn't know about genetic drift is coming from. There is clear contrary evidence in his writings. For example, he wrote this (among other things) about genetic drift in his 2002 "Sense and Nonsense" book:

"random copying of genetic material, known as random genetic drift, is acknowledged to be a major process underlying biological evolution. Models of genetic drift are sometimes described as 'the neutral model' because the variants are considered to be neutral with respect to the success of the individual."

txpiper said...

Another new view of evolution.

Maybe someday some notable person will wake up with a truly novel view, one that recognizes that random DNA replication errors cannot produce hyper-complex, integrated, highly specific and functioning biological systems.

But probably not.

O Cabrito Politico said...

Already there is a truly novel view, txpiper. The evolution we are watching as microscopyand biological beings is anything more than the routines steps of a universal process of reproduction reproduction of a natural system that triguered the Big Bang by a commom genetic process like the origin of your own body was triguered by a microspic big bang when exploded the membrane of a spermatozoon. This new view is called " The Universal Matrix/DNA for All Natural Systems and Life's Cycles", or "The Matrix/DNA Theory". So, this "evolution" has a direction and random mutations can occurs but will be selected only if fits in the reproductive process.

Rolf Aalberg said...

Directed, but nevertheless evolution, has been practised in animal breeding and agriculture for thousands of years. No big deal but very efficient. Don't tell me that the 'games' played by so many animal species aren't played for a reason and purpose.

txpiper: Evolution has inspired the invention of genetic algorithms that produce hyper-complex, integrated, highly specific and functioning ... systems. What's the difference?

Mikkel Rumraket Rasmussen said...

"Maybe someday some notable person will wake up with a truly novel view, one that recognizes that random DNA replication errors cannot produce hyper-complex, integrated, highly specific and functioning biological systems."

Surely you forgot functionally Digitally cybernetic, Irreducibly CompleKs (DICK) multicomponent machines with numerous, mutually co-dependent and intrinsically interlocking subsystems, to make sublimely integrated, electrochemicallynically engineered biochemiosmotic circuits that absolutely require a highly detailed digitally encoded blueprint to cyber-chemo-mechanically build the object, enhanced by algorithmic recursively sequentially parallel decision-making routines running on deliberaly clustered and cooperating super-computers, integrating instantiations of switch-node software/hardware mutuality that store extreme levels of directionally instructional, HYPER-Complex, specified coded information?

And they're not just "random DNA replication errors", remember the 1st rules of creationist rhetoric: It can't be overdone.
Henceforth, mutations should be named as accidentally mindlessly blind, unguidedly purposeless, functionally catastrophic, chaotically random copying-accidents.

Larry Moran said...

Hmmm ... that quote demonstrates pretty conclusively that my assumption was correct.

txpiper said...

Inspiration and invention require conscious intellect and cognizance.

Joe Felsenstein said...

Genetic drift, evolvability, niche construction, and epigenetics have not been rejected, they have been assimilated into contemporary evolutionary theory. Whether you call the resulting theory "new" is the main issue, and I argue here that we should be hesitant to do so.

I know that Russ Lande and Doug Futuyma acknowledge all these phenomena and call them part of the Modern Synthesis. Larry prefers to call them Modern Evolutionary Theory instead. The people touting the centrality of epigenetics and niche construction at the Royal Society meeting exaggerate their importance. It is hard for me to tell that from self-publicizing -- a wrong reason for announcing to the public that there has been some major overthrow of evolutionary theory.

judmarc said...

The coastline of the Mississippi is incredibly complex. Does this come from inspired water molecules?

Faizal Ali said...

Of course! How else would it conform so perfectly to the shape of the land that surrounds it?

judmarc said...

You should consider using the word, "inherited" instead - to avoid bias in your definition against non-genetic forms of inheritance. If you do that, cultural evolution fits within the remit of your definition.

Why should anyone wish to do that? What scientific power of explanation does this grant us?

Almost everyone agrees that cultural information can be inherited across multiple generations. Suddenly you will find that you can start to make sense of the blooming literature on Darwinan cultural evolution.

Ah, OK - to make sense of the "blooming literature."

Arlin said...

Yes, Joe, some people use the phrase "Modern Synthesis" to refer to "whatever we think today", a constantly moving target.

They are objectively wrong. In fact, there is a historical record showing the MS to be a substantive explanation of the causes of evolution at odds with their beliefs, and the beliefs of anyone today working in evolutionary genetics, molecular evolution, or microbial evolution.

This MS theory depends on the idea of a totipotent "gene pool" in which variation is "maintained" by a complex dynamic involving sexual mixis, recessivity, chromosome assortment, recombination, frequency-dependent selection and balancing selection. The magic of the "gene pool" ensures that selection always finds abundant variation to shift to a new optimum, with no need for new mutations. Though mutation is ultimately necessary, recombination is the engine of evolution-- which is why Simpson, Mayr, Dobzhansky, et al frequently said that the rate of evolution wouldn't reflect the rate of mutation. The ability of selection to create new forms without mutations is the _sine qua non_ of this view, and thus is the centerpiece of Provine's 1971 account of its origins (he calls it "the effectiveness of selection").

Having shown that it was possible to rationalize a neo-Darwinian view of creative selection on a Mendelian basis, they quickly went on to argue mistakenly that this was now proven and that all other views must be rejected, as per the first chapter of Fisher 1930. But this theory was a conjecture, one that fit with certain pre-established neo-Darwinian beliefs. It was adopted because it justified the creativity of selection over the objections of early geneticists that mutation, not selection, is creative.

Yet the MS theory just doesn't apply to prokaryotes, the organisms that have dominated the planet for most of its existence (only frequency-dependent selection could play the same role in the prokaryotic "gene pool"). Molecular evolutionists today have abandoned the MS and routinely invoke origin-fixation models (invented in 1969, and unknown to Fisher, Wright and Haldane) in which the rate of evolution depends directly on the mutation rate.

If we explained to Mayr or Dobzhansky or Simpson the views of someone like myself or Mike Lynch, they would say that we are confused about the causes of evolution, and they would lecture us that the old mutationist lucky mutant way of looking at evolution has been rejected and that modern science tell us that selection is the creative force of evolution because it drives shifting frequencies in the gene-pool in response to environmental change, with mutation acting merely as a source of raw materials. Everything we know about evolution, they would lecture us, is consistent with shifting gene frequencies in the gene pool.

The people who are saying "we've expanded the MS already" either don't know their history, or more likely, they just don't really care to find out. Their position is not scientific, but cultural: their first loyalty is not to science or to historical facts, but to intellectual ancestors and a tradition that they revere.

Arlin said...

bwilson295, but we don't need a new name. If we want to refer to contemporary scientific thinking, we can call it "contemporary scientific thinking". The idea that there is a grand unified explanation for all of evolution died when the MS died in about 1969.

That is, evolutionary biology has been going without a grand unified theory of evolution for almost 50 years. Obviously, WE JUST DON'T NEED ONE. Chemistry doesn't have one. Physics doesn't have one. We don't have one, and don't need one.

Any future account of evolution will simply be a collection of whatever works and not a unified conjectural theory, as was the MS.

This is another part of the failed strategy of the "extended synthesis" people, who keep trying to claim that their new theory is unified. It isn't. It is simply a pluralistic laundry list of mechanisms thought to be important.

judmarc said...


Arlin said...

Neo-Darwinism, in historical scholarship, generally means Darwin's "natural selection" (smooth change based on how the struggle for life shapes a mass of heritable variations into adaptations), without Darwin's other mechanisms (Lamarckism, direct effects, etc).

Neo-Darwinism emerged prior to genetics and was first associated with Weismann and Wallace, and the first neo-Darwinians rejected Mendelism. The Modern Synthesis or modern neo-Darwinism is a Mendelian justification for neo-Darwinism.

One should not imagine that this rationalization is inherently reductionist or gene-centered just because it makes reference to genetics. This is a very serious mis-reading of the works of the Modern Synthesis. Unfortunately it is a very common mis-reading promoted by the synthesis-extenders. Mayr, for instance, certainly did not have a gene-centered view. The view of Dobzhansky was very genetically focused, but not reductionistic AT ALL. Evolution for Dobzhansky was not individual genes mutating and getting selected, but high-level forces operating on an entire "gene pool" at once. Interactivity and epistasis were a part of this view.

Critics like Denis Noble completely mis-understand this when they accuse the "Modern Synthesis" of genetic reductionism. Mayr, Simpson and Dobzhansky are all on record fighting against the reductionism of molecular biologists in the 1960s.

Anonymous said...

"We cannot deny that these features of evolvability deeply "matter" in the history of lineages; but how can benefits for futures arise by any causal process in the here and now? (Gould, 2002 p. 1274) "

.... by also conferring an advantage in the present?
The first I heard of 'evolvability' was in the work of Gerhard and Kirshner. They gave the cytoskeleton as one example of something that conferred evolvability by allowing eukaryotes to evolve greater cellular complexity, cell movement, cell shape and multicellularity. But of course the cytoskeleton didn't evolve for that.

billga said...

If Laland et. al. have anything to contribute they will of course, with Templeton's millions deliver experimental data which can only be explained by their notions. Don't hold your breath. They won't.

Tim Tyler said...

Inheritance matters in evolutionary theory because it involves survival-related information being copied down the generations. Whether that information is encoded in DNA, in books or digital media is a side issue - an implementation detail, so to speak. Attempts to tie evolutionary theory to DNA genes are parochial - that would exclude many of our ancestors and many of our descendants and many existing living systems. The application domain of Darwin's theory is bigger than that - and to think otherwise is both small-minded, and contrary to Darwin's own writing on the topic.

Jonathan Badger said...

Surely the blooming literature deals with flowering plants and algae, which don't have cultures (although you can have cultures of the latter).

txpiper said...

"mutations should be named as accidentally mindlessly blind, unguidedly purposeless, functionally catastrophic, chaotically random copying-accidents"

That's pretty accurate, but not suitable for textbooks. You know what they say; we must keep up appearances.

Gregory said...

"Attempts to tie evolutionary theory to DNA genes are parochial - that would exclude many of our ancestors and many of our descendants and many existing living systems. The application domain of Darwin's theory is bigger than that - and to think otherwise is both small-minded, and contrary to Darwin's own writing on the topic."

Parochial indeed. A living systems approach (Laszlo would be jealous!).

To over-inflate the 'application domain' of Darwin's 'natural selection' idea is likewise both humourous and wrong-headed. Some people really don't know the proper limits of (neo-)Darwinian evolution, even when warned repeatedly and carefully by leading scholars around the world in the mainstream and by many more others who are not in the mainstream, but nevertheless understand the distortion of evolutionism and the crumbling ideology of 'memetics' coined by a biologist with culturology-envy. So, who's laughing with who, Tim Tyler?

Tim Tyler said...

Repeated warnings and laughing at the proponents won't work, what would be needed is showing the proponents are mistaken in the scientific literature. I know the literature in this field first hand, and the remaining critics of it have been getting regularly trounced for decades now. If you think you can manage this task then by all means go for it, but plenty before you have tried and failed. Your first step ought to be hitting the library to learn about the field - since uninformed critics are the most common kind - but their contributions are next to useless.

Anonymous said...

Reeling at the stupidity of Roy Soc hosting what was essentially a discussion of the project on Extended Evolutionary Synthesis, funded by the Templeton Foundation. Why are they funding it? Because they’re always looking for a way to legitimise spirituality in science. Moving from gene to organism, and some woo claptrap about directed evolution. is not progress. It was rightly rejected as far back as the mid-nineteenth century. And regarding Leland's claims for nîche construction, his is only one voice, and not the dominant one, in the Princeton "Monologue". John Odling-Smee's nîches do no more than introduce complexity into the enaction of genetically-coded behaviour and the received consequences: feedbacks, lags, indirect effects. It's still neo-Darwinian. As of course is epigenetics. Gene control, switching, etc, does not change the potential function of that gene, as coded. Modifying the expression in any way, that moderates the same function is still neo-Darwinian. Find a mechanism that CHANGES the function so that a distinct selectable and inheritable trait results with modified functionality to the original protein, then you’ve got an evolution revolution. Meanwhile, status quo, except for the gradual whittling away of science’s leverage in shaping and informing society: be it through Trump-style denial, or insidious encroachment like the gameplay of Templeton, getting headlines suggesting there’s doubt in evolutionary science, or adopting pluralism because the goalposts are wider than a barn door so surely even intelligent design can get published. These approaches are all happening now, independent of one another. The maintainers of scientific standards in our society should be closing the door to them, not inviting them in for canapés and a chat about semantics.

jb said...

I don't understand the objection to evolvability. As a climate scientist, I often see amateurs raise obvious and often important questions. Such as why do climate scientists ignore the Sun? Or how can increasing CO2 matter when the absorption of infrared radiation is already saturated at the surface? The amateur can either conclude that climate scientists are therefore idiots or corrupt, or conclude that they don't understand something and then raise the questions as an opportunity to learn something.

It seems to me that selecting for evolvability is simple. Random genetic drift in a stable environment will produce a population with organisms that have a spread in their evolvability. Then a rapidly changing environment will select those organisms able to evolve more quickly. Since I don't think biologists are idiots or corrupt, what am I missing here? Why did Gould discount this?

Anonymous said...

My question is pretty basic: what is evolvability? Increased diversity? Increased mutation rate? What? I've apparently missed something in my education.

Anonymous said...

"Evolvability" is a likelihood function for evolutionary trajectory, cf., a 3D solution space for a species, from any point in time, or a 4D solution space for any species, from all points, at any time. Problem is that you're assigning serial causality, or at least some tractable version of determinism, to an emergent property of smaller scale processes, interacting with abiotic processes occurring for a larger scale. The arena for the outcome of this tussle ("Struggle for survival") is of course played out at the scale of individual fitness, so giving survival and reproduction, and is not played out at the "evolvability" level, essentially group selection as a species. It is meaningless, and as Larry points out, bound to teleological interpretation, and has as much contribution to make as using the idiotic terms macro- and micro-evolution. As Darwin McCloud might have put it, "There can BE ONLY one". Anyway, here's p517 Futuyama (2005) Evolution (1st edition, Sinauer) …