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A minor quibble with "Intelligent Design on Trial" - Elf M. Sternberg
A minor quibble with "Intelligent Design on Trial"
I had the pleasure recently of watching the PBS Nova episode Judgement Day: Intelligent Design on Trial. The show was quite good. If you google for it, you'll find a lot of complaints about it, most of which whine that it was "biased in favor of evolution" and "didn't show the science behind ID."

Well, there's a reason for that: there is no science behind ID, and reality itself is biased in favor of evolution.

One of the things that annoyed me was the explanation of Tiktaalik. In 1999, paleontologists discovered a plain in Northern Canada that exposed a rock bed, the best date of which was exactly between the era of the fish and the emergence of the amphibians. Evolutionary theory predicted that in that rock bed one might find a transitional fossil: something with characteristics of both a fish and an amphibian.

It took four years, but they did find something like that: Tiktaalik, a fish with hefty fins allowing for motility on muddy surfaces but, more importantly, a broad head with forward-pointing eyes, very un-fish-like. The explanation for why Tiktaalik was an excellent "transitional fossil" between fish and amphibian was quite solid.

And yet, something important was missing from the discussion of Tiktaalik. Something vital.

One of the most common statements you hear from the "intelligent design" side of the argument is that, to quote Of Pandas and People, "Intelligent Design means that various forms of life began abruptly - through an intelligent agency, with their distinctive features already intact-- fish with fins and scales, birds with feathers, beaks, and wings, etc." A bizarre result of this is that the Intelligent Design yahoos, the useful idiots at the bottom of the ID intellectual foodchain, frequently write screeds (both in small-town punditocracies as well as simple letters to the editor) asking of what use is half a wing, or the partial evolution of a feather?

With questions like this, the ID people attempt to argue that there's no such thing as a "transitional" fossil form. You can't have a species halfway between a dinosaur and a bird, because, to quote from that same atrocious article I linked to above, "Imagine such a species surviving in such a miserable state over many millions of years waiting for fully-formed wings to evolve."

Tiktaalik is important not because it's a transitional form, but because it's a highly successful organism in its own right. By having a more robust undercarriage, and by having both eyes in the front, it was significantly more capable as a large organism of dragging itself to niches that prior to its emergence had probably only ever been visited by insects. The front-mounted eyes suggested that, although it had not left its icthyian nature completely behind, it was already preying upon insects its more fish-like ancestors could never have reached, and avoiding predators that were preying upon its ancestors.

Tiktaalik wasn't busy waiting for fully-formed legs to evolve. And it wasn't "miserable." (That's a value judgement, by the way. Nature Doesn't Care what we think about its day-to-day operation.) Tiktaalik ancestors didn't hope to someday have legs. Some of Tiktaalik's ancestors had stronger fins than others, and those that did found it advantageous to pull themselves up into the mud and snag a few tasty bugs. They lived longer; they had more children; stronger fins were selected. The same with the eyes; those with eyes a millimeter closer to the front found binocular vision advantageous in snagging said tasty bugs. That characteristic was selected for. Nature doesn't "want" or "wait" for these things; they happen as a consequence of living things doing what living things do within a constantly changing environment like our Earth.

While Tiktaalik happened, other fish remained in the sea, eating and breeding and following their own reproductively successful strategies. Tiktaalik found a new way to exploit a new niche. It didn't crowd out an old niche; it didn't supersede the other fishes. (Another popular whine among Creationists is "If man evolved from apes, why are there still apes?" The common and excused answer is that we didn't want the apes' niche. The horrific and true answer is that we do want their niche, we're just not done killing them all off. Evolution, even the "bad" aspects of it (again, note that's a human value judgement and Nature Doesn't Care), takes time.)

I would really have liked Nova to mention Tiktaalik's existence as a highly successful organism optimized for a specialized niche in its time and place. Tiktaalik's existence points out the vicious deception of two of the the Cdesign Proponentsists's favorite stupidities, and it would have been nice to have a biologist put the screws to ID's thumbs even harder.

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From: cgmp Date: November 21st, 2007 10:41 am (UTC) (Link)
Ming and I had a great time watching Judgment Day. Stayed up way past our bed time as a matter of fact. The scientists were fun, but the lawyers were the stars. The legal issue was whether the intention or de facto result of bringing ID into the schools was to promote a religious view point. When the lawyers found that the authors of Pandas and People had used search and replace to exchange ID for creationism, it was all over as far as the judge was concerned. And the frosting on the cake was the gratuitous perjury by the school board creationists. Oh, that felt good!

The bible thumpers have been been savaging science for millennia, so ID is not that innovative. What is really fun about it is the logical conclusion one gets to if one accepts it's basic premise. Clearly, if one accepts ID, accepting polytheism is inevitable. After all, one look at the state of the world is enough to convince anyone that it was designed by a committee.

elfs From: elfs Date: November 21st, 2007 04:34 pm (UTC) (Link)
"Oh my God! Judge Jones is going to eat Bill Buckingham!" I about fell out of my chair laughing with that one.

I thought the science was better than the law, but I'm a better scientist than I am a lawyer. I can appreciate the art of lawyering, but the point the trial attendees made over and over was that the science taught in that classroom was unlike anything they'd ever heard before, and they'd never heard it because the creationists fight like hell to keep it out.

It is this failure to teach it that has put the US in a trailing position as a producer of biological breakthroughs.
sirfox From: sirfox Date: November 21st, 2007 02:01 pm (UTC) (Link)
Half evolved feathers? I bet they were warm.
Half a wing? Like we don't have critters around who find gliding useful.
Half an eye? Since they seem to have evolved well over two dozen different times, i'd say that a light sensitive patch of nerve cells is a heck of a lot better than none.

... good grief, even devoid of any scientific polysyllables that must give them such headaches, you'd think the ID people would at least think their own arguments through all the way.
doodlesthegreat From: doodlesthegreat Date: November 21st, 2007 04:19 pm (UTC) (Link)
Silly fox. If they tried to think them even halfway, it would throw their whole belief structures so out of whack that they would topple like tenpins. Especially since the core of that system is that "man is God's chosen special child, and everything else is just trash." And for the God-fearin', Wal-Mart lovin' trailer trash crowd that gobbles this kind of crap up like catfish, that kicks out the only pillar they have to keep from jumping in front of a train.
jordan179 From: jordan179 Date: November 21st, 2007 11:33 pm (UTC) (Link)
Half evolved feathers? I bet they were warm.

This was almost certainly their original purpose. In fact if you look at the structure of feathers, they are essentially fractal designs, and it's easy to see how simple feathers might have started as a sort of fuzz of naked stalks, creating a zone of warm air against an (already warm-blooded) archosaur, and then over tens of millions of years one after another simple mutation could have caused "stuttering" and the growth of additional stalks from the stalks, until we got to the complex feathers seen on modern birds (and probably also possessed by feathery dinosaurs).

Half a wing? Like we don't have critters around who find gliding useful.

Notice how a cat flattens itself out in a long fall. Notice how some squirrels use increasingly wide membranes to first increase jump distances and then glide. The path to true flight is actually rather obvious, without any long mutational jumps required.

Half an eye? Since they seem to have evolved well over two dozen different times, i'd say that a light sensitive patch of nerve cells is a heck of a lot better than none.

Dawkins outlines this evolutionary path in great detail in Climbing Mount Improbable. The really amazing thing is that you don't even need "nerve cells" -- ANY cell able to detect light's presence and somehow communicate this to the parent organism gives that parent organism an evolutionary advantage, and once you have a tendency to produce even one such cell, even a Gouldian "random walk" will eventually result in eyes as good as the creature can profitably use.

Indeed the "eyes" argument is an emotional one. We humans happen to have one of the best visual systems among mammals, and we are very sight-centered in our mode of survival. Hence, we tend to think of vision as something exceptionally difficult to evolve: the truth is that simple vision is fairly easy to evolve. Vision at our level takes a lot of steps to reach, but all the steps are small ones.

From: (Anonymous) Date: January 17th, 2008 03:53 pm (UTC) (Link)

Another thing to do with half a wing

"Half a wing? Like we don't have critters around who find gliding useful."

There's a little-known theory called "Wing-assisted incline running" that I like better (References: http://www.sciam.com/article.cfm?id=taking-wing and http://jeb.biologists.org/cgi/content/full/206/24/4553). The researchers noticed that young ground birds (who were still unable to fly) would use their "half-wings" to help them run up inclined surfaces. It turned out that the birds were using their wings to push themselves into the ground (as opposed to away from the ground as in flight), to the point that the adults can use this technique to scale vertical surfaces. Proto-birds could have used this type of manuever to escape predators and it gives a very clear incremental progression in the evolution of wings, with each improvement being benificial (they could run up increasingly steep surfaces until their wings/muscles had evolved enough to allow flight). It has the added advantage over the gliding hypothesis that you don't need to imagine the dinosaurs climbing trees first.
doodlesthegreat From: doodlesthegreat Date: November 21st, 2007 04:21 pm (UTC) (Link)
I loved that episode. It's always amazed me that proponents of ID are some of the greatest examples of how it either is a fake, or that whomever came up with the design needed to revise the blueprints something fierce.
beanish From: beanish Date: November 21st, 2007 05:30 pm (UTC) (Link)
I would really have liked Nova to mention Tiktaalik's existence as a highly successful organism optimized for a specialized niche in its time and place.

While I have to agree with you that it would have been nice for Nova to point out that Tiktaalik was a successful species and not just a transitional form -- it would have distracted from the argument Nova was presenting about the teaching of evolution and ID/creationism (the point, in my opinion, being "ID says there aren't these transitional forms, but here's a very good one!")

Still - it was a great show, and in a way, I hope Nova can do a special solely on these "transitional" fossils or something similar to show that they are indeed righteous species in their own way, not just merely stepping stones....
elfs From: elfs Date: November 21st, 2007 06:21 pm (UTC) (Link)
The last sentence of that section is "And here we have found a beautiful example of a transitional fossil, just where Darwin's theory said we would find it."

All it would have taken to satisfy me is to proceed this triumphal note with something like "Not only does Tiktaalik have characteristics of both a fish and an amphibian, but it was a very successful animal in its own right. Creationists often ask, what good is half a leg, or half a wing? Well, here we have an animal with half a leg, and in some sense half a head, and yet it was a very successful predator for its time."

The same thing could have been achieved again during the Miller sequence explaining why genetics validated evolutionary theory. During the segment where the tree of life was shown, the implication was always that the tree was based on morphology. A very brief segue showing how genetics confirmed the correlation between the morphological tree and the genetic tree would have much more solidly driven down the nails on ID's coffin.
hydrolagus From: hydrolagus Date: November 21st, 2007 06:59 pm (UTC) (Link)
One of my fav books on evolution is "At the Water's Edge" by Carl Zimmer. In addition to being engagingly written and having an aquatic orientation, it has a good discussion of exaptations--structural changes that were set up by the improvement of an extant trait/structure that ended up being themselves useful. Sexy example: The hyomandibular bone dwindled as the generations of fishlike things moved away from using gills and toward being able to bite without sucking in. This change left room behind the head for the development of a neck and of the more complex shoulder joint which would eventually improve movement on land. That out-of-work hyomandibular shrinks and ends up as part of the tetrapod ear. There was no goal of a weight-supporting shoulder or air-hearing ear, or a halfway-evolved useless leg; just the possibility of changes opened up by changes in something else.
Bah. Ya'll probably know all this already. I just think it's cool so I go on.
And as far as I can tell, there will never BE a transitional form that satisfies the IDers, because there's not going be some wretched nonfunctional stage of critter lasting for generations.

Edited at 2007-11-21 07:05 pm (UTC)
jordan179 From: jordan179 Date: November 21st, 2007 11:39 pm (UTC) (Link)
And as far as I can tell, there will never BE a transitional form that satisfies the IDers, because there's not going be some wretched nonfunctional stage of critter lasting for generations.

More than that. If I have two creatures, A and B, and I find one transitional fossil, C, linking them, then the ID'ers may now demand two transitional fossils, linking A to C and C to B. If I find those, there now are four gaps to explain. And so on. In the end, this would logically require fossils of all living things between A and B to satisfy, which will never be found because only 1 in a million living creatures actually fossilize.

The key is to realize that the demand is illegitimate. Finding a transitional fossil between two known fossils is nice, and it clarifies relationships, but such a find is not necessary to prove that A and B are in some way related to each other (any Earth life is related to all other Earth life) nor that the transition was accomplished by evolution through natural selection (all such transitions were).

Evolution has already been, repeatedly, proven. Creationism hasn't been proven even once. Why should arguments based on "Because we say so" stand on an equal footing with ones derived from actual study of the evidence, anyway?
From: (Anonymous) Date: November 22nd, 2007 01:31 am (UTC) (Link)
Best bit with ID is to prove ID these people must prove god is flawed and left evidence, reference the babel fish argument in Hitch Hikers except instead of the fish's usefulness proving god's existence it would be the sudden jump inexplicable by evolution. Thus the ID argument logically completely invalidates any evidence of ID they try to find.
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