Re: Guns, Germs, and Steel two: Constraints and Niches
I'd be willing to say that's a faulty analogy, based on the fact that mutation is a random process, and so "available alleles" aren't really constrained in any way other than that you can only have x many. While it is true that evolution is constrained by available alleles (if you don't have an allele to process vent chemicals for energy, you won't be doing so), that doesn't mean that such alleles won't eventually become
available, as per Dawkins and Darwin.
Remember Jeremy: Much of Punctuated Equilibrium can be shown to not apply to vertebrate evolution--the entire theory was based off of prehistoric marine invertebrates.