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==Quotes "Good Math, Bad Math comment"[1]: "I'm going to ignore the simulated annealing thing; others have dealt with your misunderstanding adequately. But you comment about fitness landscapes really pushes my buttons; it's something that I've written about and talked about numerous times. For example, it's the heart of my main critique in my review of Behe's latest book. First, fitness landscapes are a piss-poor way of describing evolution. There's a lot of reasons for that, but the most important one (in my opinion) is that the fitness landscape model assumes that there's a fixed, static fitness landscape. That's just inescapably wrong. In biological evolution, the fitness landspace changes in response to the changes in the organisms that are traversing the landscape. The only way of escaping the problem with the shifting landscape is to add dimensions - lots of dimensions. That's where the second major problem comes in. We think of landscapes as something like a terrain map - that is, a two-dimensional surface of a three dimensional shape. In a landscape like that, there are hills, which form local maxima and valleys which form local minima, and it's hard to see how things can escape from those. But we're not talking about a 3-dimensional landscape. We're talking about a landscape with thousands of dimensions. For a maximum to be a trap, it needs to be a maximum in every dimension. If there's even one dimension out of those thousands where a point isn't a maximum, then it's not a trap at all. Finally, the fitness landscape arguments assume that changes can only have very small effects - that, basically, a small change can only result in a small motion in the landscape. That isn't true. There are plenty of cases where a small genetic change produces a large developmental change. And that, in turn, means that a maximum is only a trap if there's no higher point within a maximum jumping distance. Finally, your point about how the fitness landscape should have "stabilized" is just nonsensical. That would only be true if the fitness landscape was stable, and had exactly one maximum reachable from the first organism. The moment you allow two maxima, you wind up with competition, which changes the landscape, which pushes continual development. There's just no reason to believe that the landscape is so limited or so static. If you want to make an argument of that form, you need to present some kind of real evidence that that's the real structure of the fitness landscape of biological evolution. But you're not making that argument - you're just asserting it, even though it flies in the face of observed facts." [1]http://scienceblogs.com/goodmath/2008/11/evolution_produces_better_ante.php#comment-1205517
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