Jonathan Miller: Mmm. Now the objection that is constantly raised by people who hear this, to me and to you, extremely persuasive argument, they say, "Aha! But what is the source of these fruitful novelties upon which natural selection exerts its pressures?" People would say, "Well surely the novelties themselves, even if, um, they are then... pressure is exerted upon them, something has to explain the novelties themselves."
Richard Dawkins: Well the novelties themselves of course, are genetic variations in the gene pool, which ultimately come from mutation and more proximately come from sexual recombination. There's nothing very inventive or ingenious about those novelties. I mean, they are random. And, um, they mostly are deleterious - most mutations are bad. And so you really need to focus on natural selection as the positive side, and it's only natural selection that produces living things that have the illusion of design. The illusion of design does not come from the novelty, it comes from what happens to the novelty as it is filtered through.
JM: But the argument was constantly leveled about the, um, the imperceptible changes which might in fact, as they were developed and recurred, would have culminated in something as useful as a feather. They constantly emphasise the fact, what was it about that early novelty before it had accumulated to the point where it was recognisably doing an adaptive job... where could natural selection get it's purchase upon something which was no more than a pimple?
RD: Yes. Um... well it's a fair point. It's one that I've talked about quite a lot. Um... there... we... there cannot have been intermediate stages that were not beneficial. It's... there's no room in natural selection for the sort of foresight argument that says, "Well, if we're going to persist for the next million years it'll start becoming useful.” That doesn't work, there's got to be a selection pressure all the way.
JM: So there isn't a process as it were going on in the cell saying, "Look, be patient. It's going to be a feather, believe me.
RD: Um no. Yes.
JM: Sydney Bremner satirised that beautifully when he said he imagined some protein arising in the Cambrian which was kept because, "It might come in handy in the Cretaceous".
RD: Um... it's... it doesn't happen like that. Um, there's got to be a series of advantages all the way in the feather. If you can't think of one then that's your problem, not natural selection's problem. Natural selection, um, well, I suppose that is a sort of matter of faith on my, on my part since the theory is so coherent and so powerful. You mentioned feathers. I mean it's perfectly possible that feathers began as fluffy, um, extensions of reptilian scales to act as heat insulators. And so the final perfection of the sort of, wing feathers that we see in flying birds might have come very much later. And the earliest feathers might have been a different approach to hairiness among reptiles keeping them warm. Over and over again we come across, um cases where an organ starts out doing one thing and then gets modified to doing another thing.
1.Notice what an extremely demanding theory evolution is:
“There cannot have been intermediate stages that were not beneficial. It's... there's no room in natural selection for the sort of foresight argument that says, ‘Well, if we're going to persist for the next million years it'll start becoming useful.’ That doesn't work, there's got to be a selection pressure all the way.”
“There’s got to be a series of advantages all the way in the feather.”
2.Now ask yourself whether we have evidence anywhere near to being commensurate with the demands on the theory. For millions of years on end—indeed, multiplied millions of years on end—every intermediate stage must be beneficial. There’s got to be a *series* of advantages from start to finish. A continuous series.
And do we have serial evidence for this series? Do we have evidence every step of the way for every intermediate step on our way to a feather? Continuous evidence for a continuous series?
3.It won’t do to say that if we end up with a feather, then somehow it had to happen that way.
For one thing, this assumes descent with modification. But if there are vast intervals of time in which we have gaps in the fossil record, then how do you establish lineal descent?
For another thing, it assumes that an evolutionary pathway is the only way to make a feather. But that begs the question.
4. “There’s got to be a series of advantages all the way in the feather. If you can't think of one then that's your problem, not natural selection's problem.”
Observe how the theory outpaces the evidence. He takes the theory for granted.
Lack of evidence is not a problem for the theory. If you point to the lack of evidence, then that’s *your* problem.
The theory doesn’t depend on having actual evidence of beneficial adaptations. The theory has achieved the axiomatic status of an unquestioned datum.
The onus is on you to reconcile yourself with the theory.
5.Evidence is irrelevant. At most you only need to *think* of a *possible* benefit.
And even if you can’t think of one, that’s your problem.
6.No wonder he ends up saying: “Natural selection, um, well, I suppose that is a sort of matter of faith on my, on my part.”