Surprised to find myself actually listening to some Richard Dawkins stuff, his book the TBGod Delusion which is available online as an audio book, and a talk he gave to a small group titled Climbing Mount Improbable. So far. I'm only up to Chapter three of the oobook so far. I guess it's good to know what arguments he used. It's the usual stuff and I'm not up to answering much of it but I think I'll probably come back to some of it eventually that I think I can answer here.
But first it's the Climbing Mount Improbable talk I'm thinking about. He's dealing with the creati nist argument that you can't get evolution by small steps as is the evo idea because heach step has to be functioninal aod confer some benefit to the creature in order to be selected and that isn't going to happen. You can't see with half an eye and all that. I myself came up with that same kind of argument yearsx ago when I was about twenty and contemplating a set of huge anglers mounted over a fireplace in a hunting lodge I happened to be visiting with friends. I remember sitting there for a long time trying to imagine how they could have evolved step by step from a small stubby bit of bone to this huge branching crown. I reallyh coultn' see how it was possible.\
But as I watched Dawkins contructing a path of rhte evolution of the human eye, then the wings of an eagle and the bombardier beetle's explosive technique for warding off predators, I can easily enough guess how he'd deal with this antler situation too. Once you've got a stub the male elk or whatever ti was could use to butt heads with another male el,kk you can see how it would be an davantage for the butubby little antler to fgrow into larger and larger versions because each would be even more useful to the comtabive elk. \\
OK so much for that. But as I was watching I realized that there is another and even more basic problwem with his reasoning that it swseems to bme very odd he doesn't address, nor anyone else that I know of either and I can't understand whyu as it seems so obvious at the moment. I \ That is, each step in this evolutionary path depends on a mutation to produce the logical next stage from the small stubby wing to the eagle's wing, or the barely warm chemical to the explosive beetle's mixture, or the many differnt eye qualities that each confer some benefit to the possessor of them although the benefit is minimal compare d to the final result in our sophsitcated complex eyesj.
The question is how can he by counting on mutation to produce exactly the next stage in this sequence? Why should mutation do anything useful at all for the eye or the wing or the beetle" Why shouldn't it make a dent three inches below the eye that has no visual capacity whatever? Why shouldn't it put a knob on the stubby wing that makes it even less sueful for flight? In fact I had already thought along whthese lines some hyears ago at EvC forum when I was dealing with the claim that mammals evolved from repitiles as shown in the fossil record, and particularly that tyhe mammalian ear evolved from the reptilian ear. Well, the reptilinan ear is sort of similar but quite different from the mammalian as I recall, and I can't look it up now so I have to remember it and may not be remembering too accurately, but as I recall the repitilian ear has three parts to it and the mammalian four, a different number of chanblers and they are in different positions in relation to one another. Now I can certainly imagine Dawkins picture the necessary stages of repositioning and growth of an extra chambler over millions of years in perfect order to bgget from the one to the other, but as I was thinking about it at the time I couldn't imagine that you could even get to stage two, or tstage one ofr that matter because there is no way to adsssume that mutation is goinmg to produce anyhthing like that necessary stage. Why if you get a mutation shouldn't it make a chamber smaller, or put an ear part an inch beneath the actuall ear or something else that renders its hearing functioni useless? Why shouldn't mutation do anything BUT produce a useful stage from one type of ear to another?
Dawkins is assuming that mutation is just about omniscioent and knows what stage is needed next to get from one functing part to the next. But mtuation doesn't behave in usch a rational way. And in fact it doesn't behave at ll as he is imaginging it moving from trait to trait.
Mutation operates on the DNA, it changes the sequence of chemicals in a gene, changes their order in some part of the gene that is. Sometimes this doesn't affect the proteint produce t of the gene, in fact I think that itn most cases it doesn't. But in other cases it may produce a discease process of some sort. There are thousands of genetic diseases brought about by mutations. It's almos just a matter of wishful thinking that it ever produces anything beneficial to the creature at all but I suppose once ina gagreat great while it does. But such a great graeat while it hardly seems like it could every every; ever qualify as the engine of evolution Dawkins and others think it is. And then again even if it's benefitical it isn't beneficial in the sense that it builds on some previous mutation or previous condition, it just produces something else tentirelyh unrelated to that previous condition that happens to be beneficial. I'm thinking of a cse where an advanctage in proitecitng the heart in some way was produced by a mtuation but in a gene that otherwise had not produced anting along the lines of that kind of heart protection to that point. Where is Dawkins getting his idea that mtuations can produce stage after stage of anyitng at all? Purely wishful thinking.
I've made a horrendous number of typos in this post, I wonder if it's readable at all. I hope so but I'll have to stop now and see if I can find out wby sitening to it.
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