The Great Felsenstein speaks

If there is one reason to read Larry Moran’s weblog, Sandwalk, is that Joe Felsenstein is a commenter there. There are two in response to the recent discussion over David Dobbs’ piece in Aeon Magazine. First, about Neo-Darwinism:

I think I can interpret what the first tweet refers to: the Modern Evolutionary Synthesis has been challenged by people who invoke epigenetics, phenomena of evo-devo, punctuationism, and a variety of other existent and nonexistent phenomena. the Synthesis has survived all these. It has turned out that some of these phenomena either do not exist (as in the case of neo-Lamarckian mechanisms). Other such as epigenetic mechanisms have little long-term effect. The rest can be considered to be examples of the workings of the mechanisms of mutation and selection, as in the case of evo-devo phenomena.

Similarly the Synthesis incorporated neutral mutation and nearly-neutral mutation. As for the word “neo-Darwinian”, it is gradually falling into disuse. This is partly for an historical reason: it turns out that in the late 1800s there were a group of scientists influenced by Darwin who championed the mechanism of natural selection when many other scientists were abandoning it, and they were referred to at the time as neo-Darwinians.

Pinker and Coyne are using “neo-Darwinian” simply as a synonym for the Modern Evolutionary Synthesis.

“Neo-Darwinian” is also sometimes taken as a modern-day name for panselectionist. That is what you are doing. Panselectionism has lost ground, but not the Modern Evolutionary Synthesis.

Then, in a post by Larry Moran on what I don’t like:

I’m not sure where Razib Khan is supposed to have opposed neutralism and random genetic drift. You seem to have decided that “evolution orthodoxy” is not wrong but is insufficient.

Genetic drift has been part of the Modern Evolutionary Synthesis since at least the 1920s — Wrights great papers from 1931 on were preceded by papers by R.A. Fisher that made use of genetic drift and by a paper by J.B.S. Haldane in 1927 that made use of it as well. The standard stochastic process model for genetic drift is called the Wright-Fisher model, and it dates from 1930 and 1931.

Neutrality was not seriously proposed as applying to actual genetic variation until Lewontin and Hubby’s 1966 paper (no, not in Crow and Kimura’s 1964 paper, which used it as a null case but did not suggest that this was real). While neutral mutation as a source of genetic variation and change was under active consideration from that point on, the idea that it refuted the Modern Synthesis was a non-starter.

Gould was an important evolutiuonary biologist, a masterful (if ultimately logorrheic) popularizer. He did much to put punctuational patterns of evolution on the map. He was joined in this by Raup, Sepkoski, Eldredge and Stanley. Their view that this required that most major change be due to species selection is not a majority view among evolutionary biologists — their argument did not gain widespread acceptance, though it still around.

The result of all this is that the horrible, boring, overly-orthodox Modern Synthesis has been refuted and swept into the dustbin of history — leaving us with the not-so-horrible, not-so-orthodox, but still boring Modern Synthesis.

The opinions of those who are eminent actors in the drama of science have greater weight. In these domains opinions make the transition to authority, whether the speakers wish it to or not.

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