Having blown my own trumpet, I should mention that there are a few other articles in the same edition of Biology and Philosophy (which I hadn't seen until now) on Gavrilets' view of adaptive landscapes now on Online First: Massimo Pigliucci has a very nice historical summary of Sewall Wright's initial metaphor and ideas and how they changed (it hadn't occurred to me, but should have, that the landscape metaphor fails to deal with new mutations, which change the landscape itself (although I did say something like this in my 1998 paper). Anya Plutinski discusses the iconography of Wright's initial diagrams and how the metaphor has developed into a full model. And Jon Kaplan, who started me thinking about this some time back now, argues, rightly I believe, that it is time to stop thinking in terms of "picture" metaphors, and start dealing with the complex math that high dimensionality requires. I vaguely remember there was another paper coming, but if it turns up I will add it to this post.
Kaplan, J. (2008). The end of the adaptive landscape metaphor?.Biology & Philosophy. DOI: 10.1007/s10539-008-9116-z
Pigliucci, M. (2008). Sewall Wright's adaptive landscapes: 1932 vs. 1988. Biology & Philosophy. DOI: 10.1007/s10539-008-9124-z
Plutynski, A. (2008). The rise and fall of the adaptive landscape?. Biology & Philosophy. DOI: 10.1007/s10539-008-9128-8
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See also Skipper, Robert A., "The Heuristic Role of Sewall Wright's 1932 Adaptive Landscape Diagram", Philosophy of Science 71 (2004): 1176-1188. http://asweb.artsci.uc.edu/philosophy/faculty/skipper_2004b.pdf
Oh yes, Rob's paper is excellent, but I was just catching up on that special issue of B&P.
Just wondering: Did Wright specify that better-adapted creatures inhabited peaks in fitness landscapes? Seems to me this helps promote a slightly misleading "climbing" or "progress" metaphor.
Consider a creature such as the panda, adapted for minimizing energy output w.r.t. energy input, and just barely successful at it. But though the panda's "lifestyle" is a stark example, every form of life needs to do the same to survive and reproduce. Maybe a more appropriate metaphor than fitness peak would be an energy valley or well, something like electron orbits in quantum mechanics.
I can't get Jon Kaplan's paper, but if he's talking about getting rid of the current crop of evolution metaphors, count me in. It's not that the current crop are inaccurate, they are plain wrong.
I've never understood why there are peaks at all in an adaptive landscape. Adaptaion is a restrictive excercise, the more adapted you become, the more restricted are your options with regard to the adaptive landscape. There should be adaptive pits, not peaks.
Also, the the lawn/molehill/ladder/tree metaphors are woeful. We need a more three-dimentional model, like ink being injected into an aquarium (at least that has an x, y and z axis, none of which are associated with "higher", "upward", or "advanced".
It's time to do a Washington to the cherry tree of life!
I'm surprised that you're a fan of the adaptive landscape type talk, John... I dunno. I'm not big on Gavrilets (don't tell him though, cuz I'm applying for grad school at UTK and he is the only person there who I would want to work for <_<). I'm really in love with Wright's formula for the change in allele frequency (i.e. deltap=(pq/2)*(dlnw/dp)), which is definitely relevant, but adaptive landscapes are bizarrely misleading, in that multilocus systems will in general not approach a maximum mean fitness (see Ewens 2004 "Mathematical Population Genetics" for more discussion than anyone could possibly care to see).
Hrm, it screwed up my comment. Oh well. I just said that adaptive landscapes can be somewhat misleading, and that I was joking about Gavrilets. I think that his stochastic models are probably the best way to go about understanding some of the complex dynamics that will happen during speciation. My personal favorite work, though, is Orr and Turelli 2001 on the stochastic accumulation of Dobzhanksy-Muller Incompatabilities.