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Tuesday, August 11, 2015

More calls to extend the defunct Modern Synthesis

Once again, a group of scientists want to extend and revise the Modern Synthesis version of evolutionary theory in order to bring their pet projects into the mainstream. Once again, these scientists seem to have missed the real revolution that took place 45 years ago so they are attacking a strawman. And, once again, they seem to think that the core principles of evolutionary theory can be defined by how complex animals evolve, ignoring bacteria and single-cell eukaryotes that have been at the heart of the history of life for 3.5 billion years.

But the fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses. They laughed at Columbus, they laughed at Fulton, they laughed at the Wright Brothers. But they also laughed at Bozo the Clown.
                      Carl Sagan
The paper by Laland et al. (2015) was published in Proceedings of the Royal Society (UK) Series B just this month (August, 2015). The usual suspects are included in the author list including three of the Altenberg 16: Eva Jablonka, Gerd B. Müller, and John Odling-Smee. This is the same group that defended the "yes" side when Nature posed the question, "Does evolutionary theory need a rethink?" back in October, 2014 [see Rethinking evolutionary theory ].

They start with a typical motherhood statement, the kind of thing you hear from everyone who has a new idea to promote.
Conceptual frameworks are necessary in science, but they, and their associated practices, inevitably encourage some lines of research more readily than others. Hence, it is vital that the conceptual frameworks themselves evolve in response to new data, theories and methodologies. This is not always straightforward, as habits of thought and practice are often deeply entrenched. In this regard, alternative conceptual frameworks can be valuable because they draw attention to constructive new ways of thinking, additional causal influences, alternative predictions or new lines of enquiry.
The target is the Modern Synthesis of evolution. Here's how they describe it.
The Modern Synthesis (MS) emerged in the first half of the twentieth century, with the integration of Darwinian natural selection, population-level thinking and Mendelian inheritance, and has provided the dominant conceptual framework for evolutionary biology. It is rightly regarded as one of the major achievements of biology and led to the widespread adoption of several core assumptions. These include: (i) evolutionarily significant phenotypic variation arises from genetic mutations that occur at a low rate independently of the strength and direction of natural selection; (ii) most favourable mutations have small phenotypic effects, which results in gradual phenotypic change; (iii) inheritance is genetic; (iv) natural selection is the sole explanation for adaptation; and (v) macro-evolution is the result of accumulation of differences that arise through micro-evolutionary processes.
This isn't a lot different from the description that Ernst Mayr published in 1963 when he said ...
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...Ernst Mayr
That's the "hardened" version of the Modern Synthesis and it prompted Stephen Jay Gould to write that, "... if Mayr's characterization of the synthetic theory is accurate, then that theory, as a general proposition, is effectively dead, despite its persistence as textbook orthodoxy."

He later regretted being so categorical ("effectively dead") but maintains that what he said was true [see Is the "Modern Synthesis" effectively dead?]. If that's what you mean by the "Modern Synthesis," then it died—or should have died—several decades ago. Laland et al. are a bit cagey because they don't attribute all of evolution to natural selection, only adaptive evolution. The true hardened version of the Modern Synthesis didn't make this distinction.

They go on to say ...
Following the advent of the MS, the field of evolutionary biology has continued to evolve, allowing incorporation of new theoretical and empirical findings (e.g. neutral theory, inclusive fitness theory). As a result, today's evolutionary theory is vastly more sophisticated than the original synthesis and covers a broader range of phenomena.
That's a slight improvement over previous statements made by these opponents of the Modern Synthesis. Most of the time, they don't even acknowledge Neutral Theory or random genetic drift.

As far as I'm concerned, the old Modern Synthesis died a long time ago. It was replaced by a better understanding that includes Neutral Theory, random genetic drift, and heirarchical theory, to mention just a few. Macroevolution is more than just lots of microevolution and random genetic drift plays a major role in adaptation.

The authors include a table outlining a slightly different definition of the Modern Synthesis. I don't agree that this represents the classic Modern Synthesis and I don't agree that it represents modern 21st century evolutionary theory as described in the major textbooks. Thus, they are attacking a strawman.
Classical MS core assumptions
  1. The pre-eminence of natural selection. The major directing or creative influence in evolution is natural selection, which alone explains why the properties of organisms match the properties of their environments (adaptation)
  2. Genetic inheritance. Genes constitute the only general inheritance system. Acquired characters are not inherited
  3. Random genetic variation. There is no relationship between the direction in which mutations occur—and hence the supply of phenotypic variants—and the direction that would lead to enhanced fitness
  4. Gradualism. Evolution via mutations of large effects is unlikely because such mutations have disruptive pleiotropic effects. Phenotypic transitions typically occur through multiple small steps, leading to gradual evolutionary change
  5. Gene-centred perspective. Evolution requires, and is often defined as, change in gene frequencies. Populations evolve through changes in gene frequencies brought about through natural selection, drift, mutation and gene flow
  6. Macro-evolution. Macro-evolutionary patterns are explained by micro-evolutionary processes of selection, drift, mutation and gene flow
I suppose I should at least acknowledge some progress among this group. They are beginning to realize that drift is important and so is Neutral Theory. This is a big change over previous writings where those ideas never entered into the conversation. Nevertheless, I still think that most members of the EES (Extended Evolutionary Synthesis) group didn't really assimilate the lessons of the 1960s and 1970s.

What do they propose? They think that the Extended Evolutionary Synthesis should include ...
  1. Evolutionary Developmental Biology
  2. Developmental Plasticity
  3. Inclusive Inheritence
  4. Niche Construction Theory
Here are my three long-standing objections to this view [see Rethinking evolutionary theory] ...
  1. None of their claims about evo-devo, facilitated variation, plasticity, epigenetics, etc. have anything to do with evolutionary theory.
  2. All of their claims focus on only a small subset of the history of life—mostly animals. You can't reform evolutionary theory based on what you've learned about animal development because it doesn't apply to most organism and most of evolution.
  3. Their attacks on the Modern Synthesis are based on the hardened version of fifty years ago. They've missed the real revolution.
Thanks to Denyse O'Leary at Uncommon Descent for bringing this paper to my attention [New call for an Extended Evolutionary Synthesis]. She is convinced that the controversy over extending the Modern Synthesis means that evolution is in trouble and Intelligent Design Creationism is the answer [Larry Moran misses the point about Gunther Witzany].


Laland, K.N., Uller, T., Feldman, M.W., Sterelny, K., Müller, G.B., Moczek, A., Jablonka, E., and Odling-Smee, J. (2015) The extended evolutionary synthesis: its structure, assumptions and predictions. Proc. Roy. Soc. Lon. B published online August 5, 2015. [doi: 10.1098/rspb.2015.1019]

17 comments :

Ray Martinez said...

Larry Moran: "And, once again, they seem to think that the core principles of evolutionary theory can be defined by how complex animals evolve, ignoring bacteria and single-cell eukaryotes that have been at the heart of the history of life for 3.5 billion years."

There has to be a main object of explanation and complexity as found in sexually reproducing animal species is it. The history of accepted evolution says Paley's watches are the main object of explanation. He who explains said phenomena then earns the right to explain all other phenomena, which is auxiliary.

Ray Martinez said...

Larry Moran: "As far as I'm concerned, the old Modern Synthesis died a long time ago. It was replaced by a better understanding that includes Neutral Theory, random genetic drift, and heirarchical theory, to mention just a few. Macroevolution is more than just lots of microevolution and random genetic drift plays a major role in adaptation."

Sorry, but you could not be any more wrong in your facts and in your understanding.

Where did you obtain the idea that neutral evolution occurs? It had to be from theory founder Motoo Kimura. He said his theory was intended to complement natural selection, not replace, displace, or supersede. So whatever "neutral evolution" you're on about isn't neutral evolution. And I'm unaware that Kimura's theory has undergone enough revision that the "thing itself" is in need of a different name or identity. Moreover, said evolution, as seen in the term "neutral" means said agency plays no role in the production of adaptation or complexity. You've conflated two different concepts and their respective roles. Natural selection is the only concept the ToE has to explain the production of complexity. Your inclusion of neutral theory as having a positive role in the construction/production of complexity violates the rules of logic, and is thus false.

Jass said...

Ray,

Larry's theory has to be right because he hasn't seen any proof for the existence of gods Don't you get ?

Chris B said...

lies, Larry's post is about a scientific debate involving naturalistic biological principles only. Proof for the existence of supernatural gods is irrelevant.

anthrosciguy said...

One thing I thought was a good sign was the first paragraph you quoted, Larry. It was a fairly standard "paradigm shift needed, and here we are" paragraph, but with a lot of careful phrasing to avoid the phrase "paradigm shift". That suggests that the phrase is becoming too toxic, too much a red flag warning of nonsense ahead, so that even those who seem like they've be eager to use it are avoiding it. That's a good sign, albeit a small improvement.

Robert Byers said...

As a YEC you gotta love plasticity. its just saying biology changes from innate flexibility without selection on mutation or selection at all.
they invoke this because they have examples of things changing beyond normal evolution ability.

why is it that another tribe of scientists find old time evolution not bery right??
Are not svientists always right in their field?!
if these scientists are wrong then why not others?
Scientists being wrong i, in large numbers, is a option.
creationism has been saying this for a long time and were told it was impossible for science doing researchers to be wrong.
Suddenly when conclusions are not welcome its easy for them to be wrong.
Yup!!

Piotr Gąsiorowski said...

When they start reediting their planned manifestos, pasting every occurrence of "paradigm" over with "conceptual framework", sooner or later someone will blunder and the "parconceptual frameworkadigm shift" will be born.

Larry Moran said...

@Ray Martinez

I'm sorry to learn that you don't understand the modern version of evolutionary theory and the role of random genetic drift in the evolution of complex structures. Your problem can be rectified if you read up on the subject.

Mikkel Rumraket Rasmussen said...

I have already explained all of Ray's misconceptions to him before. It all started here.

Quick recap: He never got it and became increasingly incoherent and uncooperative as the same basic principles were attempted explained to him over and over again.

Chris B said...

It is the nature of science to be progressive. Theories are refined as new information is gathered, making them better and more predictive. This is a strength of science, not a weakness. The weakness is in stale, unchanging religious dogma that bogs people down in the mire of superstition and ignorance, impeding our understanding of the natural world.

"they invoke this because they have examples of things changing beyond normal evolution ability."

No, Robert, nothing being discussed in this thread is 'beyond normal evolution ability'. To the extent these other mechanisms (epigenetics, etc.) contribute to evolution, they have the potential to add to heritable genetic variation. They aren't going to replace known mechanisms of evolutionary change like natural selection and genetic drift.

Woody Benson said...

My sarcastic comments:
1. Evolutionary Developmental Biology: Is it still lagging? But with embryology’s perennial fixation on refuting Ernst Haeckel, what could you expect?
2. Developmental Plasticity: Hasn’t this been a big part of evolutionary biology since C. D. Waddington? Someone must have dropped the ball.
3. Inclusive Inheritance, considers, besides genetic inheritance, cultural (the mainstay of psychology and sociology), epigenetic (so that Lamarck can slip in the back door?), and ecological inheritance (i.e., persistent ecological features produced by organisms and probably should not even be looked on as ‘inheritance’. Or am I wrong?).
4. Niche Construction Theory: the classical idea that the actions of plants and animals affect and select (adaptationistically speaking) their own biological traits and those of other species, but seemingly restricted to indirect consequences of material modifications of the environment. It is perhaps significant that the approach has been attributed (by Laland Lab) to views expressed the guru geneticist Richard Lewontin.

Robert Byers said...

Your wrong. Plasticity is a newish idea to explain why creatures so easily change here and there from what I have read. its not evolution as usual. Thus the different name for a different thing.

Chris B said...

No, Robert, you are wrong. Plasticity has been around for a long while, and it poses no problem whatsoever for evolution.

Often creationists try to shoehorn a long recognized phenomenon into their religious beliefs, or attempt to harness it as some critique of evolutionary theory. Lacking a proper understanding of the phenomenon, they fail either way.

If you did a literature search on plasticity, you would see this is a concept that has been studied in the context of evolutionary theory for a long time.

Bill Cole said...

The challenge to the modern theory is trying to get from protein A to novel protein B though a protein coding section of the genome with random change. The possible number of ordered sequences is very large. I think this is best left unexplained at this point. The problem here on the other side is a case for how protein manufacturing architecture explains evolution. The ordered sequence that is difficult to mutate through has an almost infinite possible combinations of ordered sequences and therefore can find many novel proteins despite a rare occurrence of sequences that fold functional proteins.

Ray Martinez said...

Larry Moran: "I'm sorry to learn that you don't understand the modern version of evolutionary theory and the role of random genetic drift in the evolution of complex structures. Your problem can be rectified if you read up on the subject."

You've simply reversed the criticism that I initiated upon you. But my criticism, unlike your bare reversal, included specific argument and facts. You've been exposed as not knowing the basic claims of Kimura's theory, advocating a subjective version and, more importantly, violating the rules of logic. The concept of "neutral" in these context means positive or creative evolution is not occurring. Yet you continue to believe just that. Your error is basic and not a matter of opinion.

Ray Martinez said...

Larry Moran: "I'm sorry to learn that you don't understand....the role of random genetic drift in the evolution of complex structures."

This comment says neutral genetic evolution plays a role in the production of complexity, or the neutral contributes positively.

Logic: A cannot be A and not -A at the same time (Schrodinger's cat cannot be dead and alive at the same time).

The neutral cannot be neutral and not neutral (= positive, contribute to complexity) at the same time. Whatever neutral is it is not positive. The same are two different concepts. Therefore neutral evolution does not and cannot play a positive
role in the production of complexity.

In another thread recently Mikkel Rasmussen produced a drawing that showed positive mutations and neutral mutations. Each neutral mutation was conveyed by a horizontal line and each adaptive mutation was conveyed by a vertical line. The vertical corresponds to the production of complexity. So Mikkel's drawing complies with accepted logic and shows neutral drift to not have any role in the production of complexity.

John Harshman said...

Ray, your main problem here is that you confuse complexity with advantage. There is no particular expectation that greater complexity will be of benefit to a population. And I suspect you have no real idea what Mikkel's drawing was supposed to show you.