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Dreadful row breaks out re cladistics

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Teapots bust. From a story at Wired:

Twitter Nerd-Fight Reveals a Long, Bizarre Scientific Feud

The editorial in the February issue of the scientific journal Cladistics didn’t exactly drop with a bang. Cladistics has around 600 subscribers—almost half of which are libraries or other institutions—and it’s aimed at “scientists working in the research fields of evolution, systematics and integrative biology,” as the journal’s summary says. It’s a journal about building evolutionary trees of life, basically. Important, but harmless, right? … the editors of Cladistics were insisting that anyone trying to build those trees of life had to use a method called parsimony—that, in fact, anyone who didn’t use parsimony wasn’t doing real science.

Science Twitter caught fire pretty fast after that.

One approach for growing these trees is called parsimony. The basic idea is that the tree with the fewest number of evolutionary changes is the most likely to be true. It’s like Occam’s razor, if Occam had been an arborist. So, for example, if you built a tree that grouped gorillas with, like, tigers instead of humans, that would mean evolution had produced the opposable thumb twice (for gorillas over there and you and me over here). But group gorillas on a branch with humans and we share some common ancestor closer to the trunk who evolved an opposable thumb just once. Parsimony says, well, that’s your tree.

It’s not the only way, of course. Another approach, “likelihood,” is about comparing different trees and running computer models for how likely types of changes are. An offshoot of that, the Bayesian approach, actually calculates the likelihood of a given tree. …

Then the first pie landed in what science writer Matt Simon calls “biology’s hidden war.” He concludes,

Building trees to make sense of life on this planet is more important than ever. By using parsimony or likelihood or other techniques to group a species with its peers, researchers can infer things like behavior. … Darwin planted the tree over 150 years ago, and each day it thickens. Now scientists just have to figure out how to grow the thing without constantly trying to refresh its roots with the blood of patriots to its cause. More.

A good deal surely depends on how evolution actually occurs. Talk to the fossils: Let’s see what they say back.

Note: Nerdfight? We like it! 🙂

See also: Maybe biological classification is more of an art exhibition than a science pursuit?

5 Replies to “Dreadful row breaks out re cladistics

  1. 1
    Bob O'H says:

    I’m not sure I’d call it a dreadful row. Anyone who’s worked in systematics or who knows that crowd will already be aware of the attitude of the members of the Willi Hennig Society, and this is just them making it a bit more public so that people (like Jonathan Eisen) not familiar with the people noticed.

    The rest of us know what they’re like, and try to avoid them.

  2. 2
    wd400 says:

    As Bob says, the Willi Hennig Society are a pretty fringe groups these days. Although there used to be real debate about the efficacy of parsimony and other methods, parsimony is mow mainly seen as a stepping stone in the development of modern phylogenetic methods.

    Though the behaviour of the “leech guy” in the linked post is about what you’d expect from the Hennig Society, it can be a shock to people that don’t know there are still parsimony hold outs.

  3. 3
    News says:

    So it’s not true about the knives and forks making their way across the room unassisted? We wondered. – d.

    Sorry, the phone line transmission was bad. They were not unassisted, they were unaccompanied. 😉

  4. 4
    Robert Byers says:

    It sewems that they are not doing science at all. In fact they are using common sense for whats likely to have happened for creatures are related.
    Its about likelyness.
    Hmmm.
    its as if some things are less likely they are admitting.
    One can go from here!
    If small stepism can explain anything that why is anything less likely?
    Evolution makes everything likely.
    However common sense DOES NOT.
    So a dustup must happen in these areas now and then. Its just speculations fighting speculations.
    Sure it is.
    These people don’t know what science. They just memorized things in school and possibly bumped out better people by a few marks.

  5. 5
    DLH says:

    “Parsimony” is unable to explain the Origin Of Life with its inherent complexity based exclusively on matter and the 4 laws.

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