Tuesday, December 15, 2009

An Imminent Creationist Feeding Frenzy, Courtesy of Nature

An article just published to Nature has turned the world of evolutionary biology topsy-turvy!

Or, so they’d like us to believe…

The paper’s authors Chris Venditti, Andrew Meade and Mark Pagel have devised a new model that shows that evolution is not driven by natural selection or through the accumulative effects of random genetic drift. Rather than incremental and gradual change, their study suggests that the vast bulk of speciation results from rare stochastic events. They call this new theory “punctuated equilibrium” – NO WAIT! They don't...

Actually, they don’t call it punctuated equilibrium, which is strange because that’s what it looks like to me… What’s even stranger is that neither Niles Eldredge nor Stephen Jay Gould’s names appear anywhere in the paper – including the references.

Through phylogenetic analysis of 101 different plant, animal and fungi groups the researchers established that - what I’m going to call - the punctuated equilibrium model is the most parsimonious fit for explaining the branch lengths of the studied taxa.

Although, this ‘rediscovery’ of what’s been known for about the last 30-years may not seem too earthshaking, I’m confident that (with Nature’s help of course) creationists around the world will be harvesting quotes from the article and its associated news release.

Check out these lines:

Quotes from Nature’s accompanying news release-

“New species might arise as a result of single rare events, rather than through the gradual accumulation of many small changes over time, according to a study of thousands of species and their evolutionary family trees.”

“This contradicts a widely accepted theory of how speciation occurs: that species are continually changing to keep pace with their environment, and that new species emerge as these changes accrue.”

“The team's findings might stir things up in the world of evolutionary biology.”It really goes against the grain because most of us have this Darwinian view of speciation," says Pagel. "What we're saying is that to think about natural selection as the cause of speciation is perhaps wrong."

Quotes from around the web-

"A new study published in Nature contradicts the commonly-held belief that most species evolve gradually through sexual selection in response to subtle changes in their environment." (SOURCE)

"This new theory is likely to be quite controversial, as it goes against the Darwinian view of evolution that most people are familiar with. "It really goes against the grain because most of us have this Darwinian view of speciation," says Pagel. "What we're saying is that to think about natural selection as the cause of speciation is perhaps wrong." (SOURCE)

'The surprise is that this model is not compatible with the idea that lots of small events combine to bring about speciation,' he adds. (SOURCE)

"Our research indicates that the idea that new species occur by gradually becoming more and more adapted to their particular niches, is not true. In fact, we have found that new species appear due to rare random events that seem to simply just happen." Pagel (SOURCE)

Quotes from the study -

“The Red Queen describes a view of nature in which species continually evolve but do not become better adapted. It is one of the more distinctive metaphors of evolutionary biology, but no test of its claim that speciation occurs at a constant rate has ever been made against competing models that can predict virtually identical outcomes, nor has any mechanism been proposed that could cause the constant-rate phenomenon.”

“This model predicts a constant rate of speciation, and provides a new interpretation of the Red Queen: the metaphor of species losing a race against a deteriorating environment is replaced by a view linking speciation to rare stochastic events…”

“Speciation is freed from the gradual tug of natural selection, there need not be an ‘arms race’ between the species and its environment, nor even any biotic effects.”

“If the original Red Queen model had a ‘whiff’ of a species running out of breath from the accumulation of many detrimental biotic effects, and then being ‘knocked off’ by the next event, the interpretation we propose is different. Species do not so much ‘run in place’ as simply wait for the next sufficient cause of speciation to occur.”

“This means that researchers seeking to develop explanatory theories of speciation should focus their attention on the size of the catalogue of sufficient causes (speciation factors)
shared by a group of organisms, rather than on special driving forces or how these forces might combine.”

Venditti, C., Meade, A., & Pagel, M. (2009). Phylogenies reveal new interpretation of speciation and the Red Queen Nature DOI: 10.1038/nature08630


  1. Nor is there any mention of George Gaylord Simpson, who I believe pointed out long before Gould and Eldredge that stabilising selection was more likely in large populations and directional selection in small populations - effectively the theoretical background for punctuated equilibrium.

  2. Can anyone point me to some resources that talk about speciation being driven by the Red Queen phenomenon? This is a new one for me, but Pagal seems to be saying that this is what everyone has been thinking all along. I always thought that the prevailing model was that speciation is driven by random mutation following geographic isolation (and perhaps supported by natural selection upon secondary contact of the diverging lineages)--and also via polyploidy as in many plants.

  3. @ Anonymous

    If you have access to an academic library, take a look at Van Valen : "A new evolutionary law". Evolutionary Theory 1: 1—30 (1973). Otherwise, there is a short mention in Gould's "The Structure of Evolutionary Theory" and, if I remember correctly, Dawkins talk about it in "The Blind Watchmaker". There's always "The Red Queen: Sex and the Evolution of Human Nature", but, as the title clearly indicates, this one is more about the benefits of sexual reproduction than the arms race.

    Here is a summary : http://www.indiana.edu/~curtweb/Research/Red_Queen%20hyp.html

  4. That does sound a lot like punctuated equilibrium. Indeed, exactly like it. Are these guys claiming to have come up with the idea all by themselves? Do they reference any previous theoretical work?

  5. Do you think that when the authors use the word 'speciation' they actually mean 'phyletic evolution'? Because if much speciation is allopatric speciation then the Red Queen is irrelevant because divergence of isolated populations has nothing to do with coevolutionary arms races.

  6. To be honest, I’m not exactly sure what they’re trying to say… I view “punctuated equilibrium” and “phyletic gradualism” as complimentary processes, not as competing models. Sure we can debate about which is the larger driver for a given case, but the authors seem to be presenting the arguments as though they’re mutually exclusive.

    Here’s another snippet:
    “To the extent that this view is correct, the gradual genetic and other changes that normally accompany speciation may often be consequential to the event that promotes the reproductive isolation, rather than causal themselves. Factors apart from biotic interactions that can cause speciation include polyploidy, altered sex determination mechanisms, chromosomal rearrangements, accumulation of genetic incompatibilities, sensory drive, hybridization and the many physical factors included in the metaphor of mountain range uplift.”

    In my understanding, natural selection considers and includes phenomena such as sexual isolation, sensory drive, “the accumulation of genetic incompatibilities” and “physical factors included in the metaphor of mountain range uplift.”

    And, in regards to the rate at which selection operates, it’s not bound to “phyletic gradualism” - nor was it forwarded as such by Darwin (mentioned since ‘Darwinian speciation’ appears in one of the above quotes).

    In the quoted interviews, Pagel certainly gives the impression that their model is providing novel and unique findings… But I don’t know if they’re taking “credit” for punctuated equilibrium or not?

    Kinda strange…

  7. Nature does seem to be doing its best to live up to the 'tabloid' label some folk give it.

    The whole think seems like a plundering of Eldredge and Gould (including the central thesis of Wonderful Life). It seems the creationists aren't the only ones who know the value of putting new labels on old ideas.

    Mike from Ottawa

  8. Quite true Mike – unfortunate but true…

  9. True but quite strange at the same time. It's not exactly like it was an obscure idea proposed in an even more obscure journal 75 years ago. I can't believe they thought they could get away with it if they actually did it knowingly.

  10. Several of Pagel’s past publications mentions punctuation specifically: http://www.evolution.reading.ac.uk/Publications.html

    Whatever the deal may be, it's not an oversight...