Read the full paper… they are making the point that a lot needs to be done before accepting natural selection as an over arching theory of evolution.
" Moreover, for natural selection to earn its reputation as a powerful theory of how evolution occurs , the theory must be developed far more than it has to date, with a focus on testing and improving evolutionary predictions."
Along these lines, Orzack (2010)19 has called for an Adaptationism Project akin to the Human Genome Project. This project would conduct and collect rigorous studies from around the world and establish in as many real circumstances as possible whether natural selection was the primary agent in observed evolutionary change, a fact that is simply assumed by adaptationists.
Developing natural selection as a theory will require developing a detailed set of filter theories for particular circumstances. These sub-theories will, after testing in numerous experiments, eventually allow development of what may be labeled “principles of evolution.”
My objection is that you were talking about phenotypic evolution, which is overwhelmingly what most people mean when they talk about “evolution”. To say that natural selection plays little role in evolution will be completely misleading to most people, even if technically correct.
How do you know what I am talking about without asking me?
And how will knowing the truth that natural selection plays little role in evolution mislead people?
What exactly are you defending here?
Reread the exchange you were engaged in. You were supposed to be providing peer-reviewed papers that claim that natural selection is a tautology. This paper does not do that.
Do you really want to discuss the meaning of the paper or hide behind technicalities…
The paper is clear. In cases where natural selection is described non-tautologically… we don’t know enough to make testable predictions…
They write-up
" Summing up: we are saved from tautology by the propensity interpretation(s), and its reliance on “expected fitness,” but with a cost: we must acknowledge that there is no a priori property or value of fitness or expected fitness – as Gould and others have argued. The way in which we define fitness or expected fitness is necessarily arbitrary."
Then they go on about ways to properly define fitness empirically… This is something yet to be done. The point I made remains…
No predictive ability… hence impossible to test.
One objective metric is the number of mutations fixed.
Also @glipsnort I agree in all but nuance with what you are saying. I’ve been emphasizing here the role of neutral evolution as quantitatively more important for explaining DNA, and also explaining that many phenotypes are not adaptive, but neutral. That is all true at same time as acknowledging the role at times for positive selection.
My general procedure for knowing what people are writing about is to read the words they actually write. You wrote “If molecular evolution is largely neutral… then this should apply to phenotypes also”. That displays the kind of confusion I just described.
It will mislead them because of the confusion I just described in the post you just quoted. We’re in a thread discussing “design” in evolution, right? In that context, dismissing natural selection as unimportant in evolution will make most people – including you, it seems – conclude that natural selection has little role in the appearance of design. That would be an incorrect conclusion.
I’m not defending anything. I’m trying to explain the current state of evolutionary biology.
Yes it will… And I don’t see why it shouldn’t.
Are you claiming that natural selection is responsible for all appearance of design in organisms?
Do you have any evidence?
Absolutely. As long as we’re being clear that that’s what we’re talking about, I’m in.
Yup. I happily correct people who treat evolution as nothing but natural selection, but I also correct people who think that contemporary evolutionary biology has somehow removed natural selection as crucial to adaptive evolution.
Well you are the one claiming all appearance of design is due to natural selection… I am interested in knowing how you came to that conclusion…
How does a scientist measure “appearance of design”?
You have misunderstood the paper. A non-tautological definition of fitness makes few (not zero) testable predictions about the future behavior of particular populations. Thus from the abstract, “However, this re-framing comes at a cost: it reveals, based on our current knowledge of evolutionary forces, the lack of ability to make accurate predictions about expected changes except in the most simple of circumstances.” That fact does not mean that the action of natural selection cannot be tested for. I already gave you one example of a trait that has been shown to be under positive selection, which would not be the case if NS were actually impossible to test.
I take your point… however it shows that you can’t test for the action of natural selection in the vast majority of the cases… meaning any statement saying natural selection is responsible for appearance of design can only be true scientifically for the few testable scenarios… and that is assuming the test shows significant impact of NS.
I’m laughing now because this is the original question asked 73 posts ago… Is there room for discussing design within a framework of evolution? If so, what are the rules. This thread is really a perfect example of why there is so much confusion between different camps, and even animosity.
I can see now that this arena (evolution, per se) is incredibly problematic because the basic description of what evolution is, its elements, and how they manifest, are dynamic and changing even right up to the present. So this:
… I believe, at least, is really one of the most important topics to discuss and clarify… and, especially, insure that we are using the same terms in the same way.
I’d be fascinated to know how I came to that conclusion, too, since I don’t recall ever reaching it.
By and large we don’t. As a scientist I have read scads of papers on natural selection, heard even more talks on the subject, and written and spoken on the subject myself numerous times, and I have never encountered the concept of “appearance of design”. When it occurs in debates about evolution, I treat it as an intuitive, nonscientific concept.
We can only make predictions about future behavior in very limited cases. (But important ones – we can predict that drug resistance in malaria parasites will spread, for example, and that pesticide resistance in mosquitoes will increase in frequency.) How often we can test for past action of natural selection depends on the time scale, the species, and the kind of data in question.
Well read a few posts up… you said you were concerned people would misunderstand and think appearance of design is not due to natural selection. Your statement is given below. If it’s an intuitive non scientific concept… why are you talking about it ?
So here is the thing. You are worried people will misunderstand about “appearance of design” which is a non scientific concept.
You are worried about thinking NS didn’t have much to do with evolution, though you yourself admit that it doesn’t make testable predictions except in very few specific cases.
So why are you worried. The concern does not look scientific to me… why worry about something largely untestable? And proven to be not very influential in molecule evolution?
What exactly triggered your reaction?
@Ashwin_s, just to give you a bit of perspective, @glipsnort is among the most honest, thoughtful, and competent scientists in the conversation. He has been engaging the public on this for well over a decade. He is speaking form the point of view of a scientist trying to clarify what science does and does not say.
I’m sure, he is worried about this because of all the scientific claims put forward by the ID movement (and by atheists!) about a largely non-scientific topic. That is an appropriate concern.
I also know that it seems like what I have said and what he says is in conflict, but it is not. We are talking about two different sides of the coin. You can trust what you hear from. I have never heard him overstate the evidence.
Thanks for your feedback in this thread. It has been helpful in understanding this complex issue that effects different domains in different ways.
What I am really hoping to understand is, when the term “design” appears in scientific literature (and it does quite often because it very natural to say for instance that camouflage was designed to allow predator or prey to avoid detection), what does one in your environment really mean when that term is used?
I think that “design,” by definition, includes an element of “intent” which cannot be incorporated into methodological naturalism. But I understand that “design” may be the most simple way to convey that one thing fits well with another. So, when one sees this kind of hand-and-glove synergy in the lab (where it may be tempting to use the word “design”), how does one perceive that “apparent design” because it could not be due to design with intent. The science itself does not allow for that.
I hope that makes sense. This is the gist of what I was hoping to get at when this thread began. And, if you have time, how many is a “scad?”
