Grey Thoughts
Evolution - No more just-so stories?
Michael Sprague, from Philosophy of biology, has responded in the comments of my last post, ID - "Causing" problems

Apparently, I did not understand his original comments and he makes a bold claim
Evolutionists, professionals that is, realized the worthlessness of just-so adaptationism decades ago. You will not find it in contemporary evolutionary biology.

Well, that sounds like a challenge I guess.... Can I find any instances of just-so stories in contemporary evolutionary biology? Apparently, there hasn't been that sort of thing for decades according to Michael.

I didn't have far to go it seems Science Now has an article by Bill Hannson describing the evolution of the Robber Crab's nose
When the ancestors of robber crabs first walked out of their watery environment to live on land, their sensory equipment needed a makeover. The olfactory receptors on the antennae of marine crabs detect soluble, water-loving molecules. A landlubbing crab must zero in on molecules that waft through the air
Hannson called this "a great example of convergent evolution" and continued with "The robber crabs have reinvented their smell for land so remarkably that they can even smell water"

Priceless and within the last few months.

But then again, maybe it is all a fluke? Maybe there was just one article?

Nature has another article from may last year on Sharks and Tuna
Adam P. Summers, “Fast Fish,” Nature 429, 31 - 33 (06 May 2004); doi:10.1038/429031a.
Swift-swimming, open-ocean hunters such as mako sharks and tunas need a big engine. Despite their long separation in evolutionary terms [sic], the internal drive systems adopted [sic] by these fishes are much the same.... after 400 million years [sic] of separate evolutionary trajectories, these two high-speed predators have converged on solutions to the problem of swimming fast that go from skin to skeleton
Yup. They went and got those big engines because they needed to swim fast.
Strike two...

Nature advance online has an article on the evolution of feathers
These results suggest that the barbs form first and later fuse to form a rachis, much like downy feathers are formed before flight feathers when a chicken grows up. Under the general rule of ontogeny repeating phylogeny, downy feather made only of barbs probably appeared before the evolution of feathers with rachides and capable of flight. However, pinning down the exact moment at which dinosaur scales become chicken feathers is non-realistic. Just like Rome, feathers are not made in one process. It took 50 million years for Nature to refine the process, to transform a scale into a flight machine. There were many, many intermediate stages. While Darwin’s theory has explained the “why” of evolution, much of the “how” remains to be learned. Evo-Devo research promises a new level of understanding.
Strike three, you are out.

Evolutionists almost always use just so stories. And you would think that someone who runs a blog called Philosophy of biology would understand that As we were not there when features "evolved" we can only put forward plausible explanations. We cannot experimentally show how it happened as we did not observe it happening. Thats the crux of the problem with Historically based sciences. You can only deal with "might have's".

So much is predicated on the belief that common descent evolution explains every creature feature out there. But this is just an assumption. Thats why we get rubbish explanations like 'convergent evolution' or it 'solved the problem of how to swim fast'.

Michael then complains that he did not introduce a straw man, but then, he has missed the point. He discusses who and what the designer is and yet the arguments for intelligent design are about detecting design, not about the nature of the designing. This is made abundantly clear, time and again.

So for the cheap seats at the back. ID is about detecting design. Deal with that argument and forget talking about the identity of who might have designed it. That is a different question and one that is not being dealt with.

Michael continues
Nor did I introduce a straw man. To do so would be to assume that the designer's god, argue that god doesn't exist, and thereby conclude that ID is false. I did not do so.

Actually, he did something similar. He introduced the concept of God (or aliens) into the discussion. Now as this was not part of the original discussion, was it put there to take a cheap shot? Create the impression that it was a religiously based argument perhaps?

Perhaps 'straw man' is not the most accurate term, it is more an attempted guilt by association type fallacy. So I apologize for the misappellation.

The original quote from Michael "But let's suppose for a second that Nelson can tell a story about how god (or aliens or whatever the designer is) could have made RNA. I take it this is supposed to give us reason to think that god in fact made RNA."
does seem to highlight the double standards he is using. He is assuming that evolutionary biology and evolutionists in general, have shown that common descent evolution as something more than a possibility. That is, they are assuming that to state that evolution "could have made " strongly supports the idea that evolution DID make that feature. Yet when an ID person claims that design can create (and not only can create, but also is more likely from what we know), the evolutionist, such as Michael scoffs at the very progression they themselves used.
Pot. Kettle. Black.
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I think maybe you need to ask someone what a just-so story is. An adaptationist explanation is not a just-so story. A just-so story is exactly what Nelson claims is the reasoning behind ID, a "causal sufficiency claim." I don't see how any of your examples are examples of this. After all, you haven't discussed the evidence at all in any of your examples.
Allow me to elaborate. When thinking about explanations for things, you can imagine two kinds of stories one can tell. A "how possibly" story (Nelson's "causal sufficiency claim") is a story about a way that the explanandum may have occurred. On the other hand, a "why necessarily" story is a story that shows why the explanadum must have occurred, given some laws and initial conditions.

The bad use of just-so reasoning has two parts: First, it proposes a "how possibly" story, then it treats that story as though it were a "why necessarily" story. In other words, it involves dreaming up an explanation, then asserting that that explanation is true simply because one dreamed it up.

None of this has anything intrinsically to do with adaptation. (It's only because this bad reasoning was used so often by adaptationists that it became associated with it.) Your examples are examples of adaptationist explanations, but this doesn't show anything about their status as just-so stories (or not). To do that, you need to evaluate the evidence on which those explanations are put forward.

This brings me to another point. You imply in your post that evolutionists accept evolution because it's all one big just-so story that can't be confirmed or tested. This is false.

For one thing, evolution can be and has been tested. Now, it can't be tested in the naive way you creationists like to focus on; that is, we can't predict that a horse will evolve into a unicorn and then go see if it does. But we can make predictions of the form, "if evolution has happened, we should find X when we look at Y." Make enough of these and it starts to add up to a pretty damn good body of evidence.

I know you're probably thinking "nonsense! they don't make those predictions! where's an example?" I don't claim to be well qualified to give you examples of these sorts of predictions, but you can read all about them in a standard textbook like this one.

A second reason for accepting evolution is its power of conscilience; its ability to unify so many observations under one theory. The theory of evolution explains myriad phenomena in such previously-independent fields as phylogeny, geology, biogeography, anatomy and paleontology, as well as later discoveries in genetics and molecular biology. The fact that so many otherwise-unexplained facts can be explained by a single theory is strong evidence for the theory's truth - at least if the "hard" sciences are any model.
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