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Punctuated Equillibrium- Orthodoxy or Not?


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A few weeks ago I came across this review by Ewen Callaway of a recent biography of Stephen Jay Gould (one that looks pretty interesting, actually, I'll have to get to it at some point): Review: Stephen Jay Gould and the Politics of Evolution

The review briefly talks about the intellectual connections between Punctuated Equilibrium and leftist-Marxist politics ('Communist biology'), which is interesting enough, but it was this statement that particularly caught my attention:

Punctuated equilibrium never caught on as a new theory of evolutionary change among most scientists. Critics had good scientific reasons for rejecting it, but the link between punctuated equilibrium and liberal politics surely didn't help.

 

Now this was news to me. All the introductory biology texts I've used in high school and thus-far in college have included Punctuated Equilibrium as pretty much orthodox. The authors, two anthropologists, of the book I'm reading right now, actually, Stones, Bones, and Molecules allude specifically to PE to support their notions on cladogenesis in human evolution.

 

So, who's wrong here? Is Callaway off in his reading of the biological consensus, or does PE as articulated by Eldridge and Gould really mostly exist as a 'popular' theory that gets put in introductory textbooks and used by nonspecialists (like anthropologists, I suppose), but which Serious Biologists maybe don't put as much stock in, or only see as a popularization and generalization of more basic work by other researchers?

 

Edit: Misspelled 'equilibrium' in the thread title. I don't think I've ever gotten that word right on the first try.

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Well, I'm dense about the "politics," but punctuated equilibrium, most simply, is just saying that sometimes the evolutionary process results in change more rapidly than at other times. It is a common misinterpretation that punctuated-equilibrium is something separate from and opposed to gradualism, and that I would guess is the likely source of the... confusion.

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Indeed. It is often confused with saltationism. But as Azure pointed out, it just states that the evolutionary rates are not constant.

Depending on perspective (e.g. from the molecular viewpoint) this is for the most part a non-issue.

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From the paleo perspective, PE is pretty widely accepted as a valid mechanism. It's a pretty common occurrence in both marine invertebrates (where SJG first noticed it) and in terrestrial ectotherms. Of course, it's not the *only* mechanism, and it's pretty much lost all vestiges of politics, but it's pretty widely accepted, IME

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Indeed. It is often confused with saltationism. But as Azure pointed out, it just states that the evolutionary rates are not constant.

Depending on perspective (e.g. from the molecular viewpoint) this is for the most part a non-issue.

 

Ok, perhaps, but punctuated equilibrium has paleontological consequences that rather differ from phyletic gradualism. Eldridge and Gould are saying that 'gaps' in the fossil record represent real data: evidence of rapid evolutionary change and the splitting of lineages. At least, that's how I've always read where I've seen it used. I don't think Gould ever said that on the generation-to-generation level evolution wasn't gradual, but that doesn't seem to answer my question as to whether-or-not his general program is broadly accepted by scientists today. By 'general program' I suppose I mean whatever Callaway means.

 

The statement that punctuated equilibrium has been rejected by 'most scientists' just surprised me.

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It's also worth noting that, IME, anthropology is very much "its own little world", somewhat insulated from broader biology and paleontology. I've been consistently shocked at the paucity of non-primate references in primate functional morphology and locomotion literature, as well as the seeming collective focus on one aspect of a system to the near-exclusion of other questions (more interesting ones, IMHO).

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IMHO, there is nothing that SJG said that is in the slightest unorthodox. If I remember correctly, and CDarwin has summarised these arguments, the hypothesis about evolutionary change has to be based around whatever fossil records there exist. However, it is somewhat ridiculous to suggest that biological theory can be based upon political principles of upheaval and revolution, resulting in rapid change. In fact, policies that were based on Marxist philosophy relied upon the original work of the philosopher and logician Hegel. He saw life as a struggle between opposites : 'thesis' and 'antithesis' which then resolved in a 'synthesis.' http://www.hegel.net/

 

IIRC, Marx and Engels work was not holistic in nature and its dialectical materialism seems to be based upon practicalities of economic theory and the materialistic idealism that would state that the current system is destined to be the best. As a work of Science, it barely explained the mysteries of Nature which even a man of Hegel's talent could not explain.

 

The 'Marxist' Science which has been performed in the light of a Marxist ideology was actually more Lamarckian in tone and has been termed Lysenkoism. This man, Lysenko, was an idiot and embarked upon bizarre Lamarckian science without an empirical framework, eventually leading to crop failures in the Stalinist USSR. http://en.wikipedia.org/wiki/Lysenkoism To attempt to put S.J. Gould, an accomplished scientist and polymath, in the same light as apparent liberal science shows huge ignorance of the scientific method itself. I don't think S.J. would have been so obtuse. As to the O.P., I have not read anything which rejects punctuated equilibrium as being against scientific orthodoxy. It is a working hypothesis based upon evidence.

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The 'Marxist' Science which has been performed in the light of a Marxist ideology was actually more Lamarckian in tone and has been termed Lysenkoism. This man, Lysenko, was an idiot and embarked upon bizarre Lamarckian science without an empirical framework, eventually leading to crop failures in the Stalinist USSR. http://en.wikipedia.org/wiki/Lysenkoism To attempt to put S.J. Gould, an accomplished scientist and polymath, in the same light as apparent liberal science shows huge ignorance of the scientific method itself. I don't think S.J. would have been so obtuse.

 

Well, just addressing this, Gould himself drew some of the connections. He wasn't a politically timid man, and he was perfectly willing to cross-fertilize his politics with his science (if not vice-versa). I wouldn't call Lysenkoism particularly Marxist, either. Lysenko suited Stalin because his 'work' supposedly supported the collectivization of agriculture, which Stalin wanted to do anyway to push along industrialization.

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Punk eek is relevant, and it certainly hasn't been rejected by most scientists, but it's far from being as relevant as "nonspecialists" think it is, Gould is seldom quoted in journals like "Evolution", and for good reasons. So I'd say it would be more accurate to say most evolutionary theorists just don't care. I'm writting my thesis on speciation and the shape of phylogenetic trees (and how to make inferences of macroevolutionary processes using them), which is arguanly the topic Gould was most interested about, yet I doubt I'll even quote him once.

 

As a side note, I particularly dislike Gould's style of writting. Too often, his texts are vague, crippled by long and unnecessary analogies to completly unrelated subjects, and even worst, he has a tendency to make a big deal out tiny details, e.g.: the difference between the words "framework" and "foundations".

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