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A Darwinian transition to a new species, photographed on an American highway!
Kristor writes:
Among other things, I was for a long time a whitewater guide. One of my old boating friends sent me this photo, which I find just amazing.
It’s like a flying fish, but on land. This is just the scenario that the Darwinians are envisioning, when they suggest that sturdy fins/proto-legs would have come in handy for fish in muddy waters—like catfish—who needed to get over a sandbank.
Of course, the photo is also plain evidence of intentionality in the catfish. He is a catfish on a mission. He is not just flailing about like an idiotic machine. If he had been, he would have stayed with the easier option, and remained in the river. But not this catfish. He is exploring. He is the Henry Hudson of catfish. Anyway, what is this “need” the catfish feels to get out of the water and risk death for no reason? How can a Darwinian speak of the catfish’s “need” to do something totally at odds with his own neural machinery? How the hell can a catfish feel a “need” to cross a two lane highway? Is the catfish not feeling an intense need to get the hell back into the river? Of course, it could just be that some fool caught a huge catfish and staged the photo.
LA replies:
Very funny.
But, to be fair to the Darwinians, they don’t explain the transition to a new species in terms of need or intention, as you suggest they do, but in terms of accident plus survival. It would have gone like this.
A bunch of catfish (or let’s call them catfishes to maintain a distinction between plural and singular), due to some environmental change, perhaps a drought, or a storm that threw them out of the water, found themselves on mud instead of water. Most of the catfishes died, but one catfish, whose forefins were particularly strong, managed to crawl his way back to the water and survive. This surviving catfish had offspring and passed on his genes to them. Then, generations later, another drought or wave left another bunch of offspring of the first catfish similarly stranded. All of them died, except the one with unusually strong crawling-fins. This happened over and over, oh, hundreds of times, thousands of times (because evolution has billions and billions of years, excuse me, millions and millions of years, to work its magic), until there was a population of catfishes whose fins were so strong they could crawl for some distance if they had to. But of course the catfishes were still fishes, and would die after a few minutes out of water. Then, eons later, an even worse disaster happened, with the catfishes stranded much farther from the water than previously. However, among the catfishes in this impossible situation there was one catfish whose gills had had a random genetic mutation, meaning an accidentally miscopied gene, that enabled its gills to extract oxygen from air. (Of course the Darwinians say there would be many intermediate stages, each one the result of an accidentally miscopied gene naturally selected, between water-breathing and air-breathing functionality. But, really, what kind of intermediate stages, each one naturally selected for its survivability, could there be? Either you can breathe air, or your can’t.) So this catfish was able to survive out of the water for a longer period of time than any fish had previously done and so it had time get back to the water alive while all its siblings and cousins died. Then, generations later, there was another disaster washing the descendants of that catfish much farther up on land. And their combined crawling-walking capabilities and air-breathing capabilities enabled them to remain on the land for long periods of time, and they became the ancestors of the first amphibians.
So you see, Kristor, it’s not right to reduce Darwinian evolution to a caricature as you have done. Darwinian evolution makes perfect sense, once you understand it correctly.
Kristor replies:
Well, I can make up some intermediate stages between water breathing and air breathing. Say you had a whole troupe of catfish that had discovered plants on land, and they would “hold their breath” and go up on land, in just the same way that whales and humans hold their breath to dive. They would take a big gulp of water into their gullet and slowly let it out through their gills or something, to give them some more time. The catfish that were best at this would have a whole new food source. Say they developed special sacks above their gullets, to hold a bunch of water on their terranean sojourns. After a while, they got to the point where they could keep going with just a film of water on the inside of those sacks. Et voila! Lungs.
My gosh, it makes perfect sense! But only if there is constant pressure to keep going up on land. But where would such pressure come from? Where is the pressure for us to go into outer space, or for Henry Hudson to try to find the Northwest Passage? Where is the pressure that is pushing that catfish up on the highway?
It can’t really be conceived. There is no possible way that the catfish is being pushed up onto the land. There is no way that his situation in the river is so bad that he has better prospects on land, just as there was no way that earthly poverty would push us to space travel. If it was just about the economics of the situation, the catfish would stay in the river, and the astronauts would sell Buicks or something. As the leftists always say about space travel, “Let’s spend our money fixing the problems we already have here on Earth before we go gallivanting off into space.” If it’s just about the low fruit, just about the least path, then there is no vision, no enterprise.
This is why asking what might “push” the catfish up on the highway is just wrongheaded. Push is the wrong analogy. I was only half-joking when I said that the catfish was on a mission. Look at him! He’s not simply thrashing about, he’s going somewhere—away from the water. He really does seem to have a destination, even if it is just the other side of the road and back. The catfish is being pulled. He has an idea he is seeking to actualize. Shoot, maybe he sees a calf in the pasture across the road and wants to drag it home for the kids.
LA replies:
Or:
Why did the catfish cross the highway?
To get to the other side.
Or rather:
Why did the catfish cross the highway?
To evolve into a salamander.
LA writes:
By the way, that’s a marvelous photo.
Kristor replies:
It is truly striking, isn’t it? That is one big catfish. Looks like he could take down a Harley. Amazing. I would actually think twice about messing with him. Not the sort of thing one wants to meet up with in a dark alley.
OK, I’ll stop now …
Larry G. writes:
Kristor wrote:
“It can’t really be conceived. There is no possible way that the catfish is being pushed up onto the land.”
Has he never heard of a dogfish? ;-)
Some twenty years ago I was visiting Australia on vacation. One afternoon—I believe it was in the city of Cairns—I sat down on a low concrete wall by the edge of the water to eat my lunch. The tide had gone out, and after a while I turned to look out over the inlet. There on the mudflats were dozens of mudskippers. These are the fish that are able to “walk” on their front fins and spend substantial time out of water. I had imagined that such creatures were only found by dedicated nature explorers wading through pirana infested rivers and coming out covered with leaches. But there they were, right in the city, watching me eat my sandwich and going about their business, whatever it might be. It didn’t occur to me at the time, but I wonder if they come there knowing that people will toss them bits of food.
LA replies:
The Aquarium of the Pacific has this description of the mudskipper:
[they look like] torpedo-shaped gobies. They have muscular, arm-like pectoral fins that function as legs when they are on land; two dorsal fins; and, depending on the species, their anal fins can be joined to form a sucker that aids in climbing. A muscular tail allows them to “skip” over land. Mudskippers also have lateral lines on their foreheads. Early in the larval life of these fish, their eyes migrate to the top of their head, where they are located close together. Internally, their protuberant eyes have cones above for color vision and rods below for monochromatic vision, allowing the fish to see both above and below water at the same time.
Mudskippers have adapted to an amphibious lifestyle so that they can shuttle back and forth from the water to land. Many of these fish actually spend 90 percent of their time on land! When in the water, they breathe with their gills as most fish do. Before climbing out onto land, these fish fill their over-sized gill chambers with water, creating an oxygen tank that allows them to breathe out of water. [LA comments: Did Kristor know about the mudskipper when he joked about how the catfish could evolve so as to live outside water?] On land, these fish also moisten their gills periodically by wiping them with their fins. To get additional air, mudskippers can also breathe through their blood capillary-rich skin, and blood-rich membranes in the back of the mouth and throat. They often keep their tails in water and roll in puddles to keep their skin moist. Mudskippers’ fins have adapted so they can walk, jump, swim, and climb. Their pectoral fins are used to move about on land where they don’t actually walk, but instead move in little hops by keeping their bodies rigid and jerking forward on their fins. This movement is called “crutching.” The pelvic fins of some species are joined together under the body to form a type of sucker that helps these fish creep up rocks and mangrove roots.
A blogger at the Aquarium’s blog who quoted the above information comments:
All of the above is interesting in itself but to me what make mudskippers extremely endearing is their behavior. They jockey for position on the rocks above the waterline by making little “skips” and will display their iridescent blue tipped dorsal fins to intimidate other mudskippers like dogs will raise the fur on their backs in a threat display to establish hierarchy. Skippy takes this dog imitation one step further by climbing up the side of the rock wall and out of the tank when called by Aquarium staff when the display is opened from the top for cleaning and feeding. Aquarium Vet Tech Colleen trained this behavior to the point that she can call the little mudskipper up onto the ledge at the top of the exhibit where she can feed Skippy in peace without having to worry about the venomous sea snakes below. Of course its one thing to describe how Skippy climbs up out of the tank, its another thing to actually see it done so I’ve included in this blog a video clip of Skippy the Mudskipper: [see video link]
[end of quotations.]
Unbelievable. Amazing. The very things that I and Kristor made up as a joke actually exists: the strong pectoral fins that propel the fish on the land, the internal water chamber allowing the fish to get oxygen. At the same, time, the unlikelihood of such innovations coming into existence by Darwinian process, and, in the case of the water chamber, as seems to me, the impossibility of it, remains the same. The internal water chamber would take many tiny little steps to come into being. But until there was an actually functioning internal water chamber, none of the intermediate steps would be selected. Not only that, but the accidentally mutated water chamber could only be selected if the mutation had occurred in a fish that for accidental reasons found itself on land. And then there’s the problem of both the strong “walking” fins and the internal water chamber having to appear in the same organism.
Here I disagree with Kristor in his dismissal of purpose. I think there is purpose in evolution (meaning of course evolution in the generic sense, as the appearance of new and more complex life forms, not Darwinian evolution which is one explanation of evolution). I think that life inherently contains potentialities and is driven to fulfill those potentialities.
LA continues:
Also, did Bob Dylan know about the mudskipper when he wrote the early ’70s version of his song, “You Ain’t Goin’ Nowhere,” with its last verse that goes:
Buy me a ring and gun that sings
A flute that toots and a bee that stings
A sky that cries and bird that flies
A fish that walks and dog that talks.
Kristor writes:
A dogfish! LOL!
My boating friend writes to say that he has been thinking of that fish as a salmon. Which really makes a lot more sense; the salmon is swimming upstream to spawn, would normally swim up the creek through a culvert under the highway, but the flooding means that the culvert might not be apparent to the fish.
Nevertheless, crossing the road to spawn still seems like a totally intentional act.
Truly amazing about the mudskipper. I had no knowledge of the mudskipper or its internal water tanks when I made them up for the catfish. Note that they can absorb oxygen through their “blood-rich membranes in the back of the mouth and throat.” If those are not proto-lungs, I’m not sure what might qualify as such.
Not quite sure how I gave the impression that I dismiss purpose as a factor of evolution. I meant to do the opposite. Under the standard Darwinian hypothesis, there is no room for purpose. Thus there is no way for the salmon to intend to swim back to his spawning grounds, no way for the catfish to intend to climb out of the river onto the highway, no way for the mudskipper to intend to climb out of the tank to get some food. No; for the standard Darwinian hypothesis, all these behaviours that are really insane for a fish are totally meaningless. They are not “about” anything at all.
So far as I can tell, the only possible way to make sense of Darwinian evolution is to posit that purpose is operant in the process at every stage. The mudskipper has evolved proto lungs and proto legs because many generations of mudskippers have intended to explore the mudflats. Intention provides the pull that moves a species to new territories, new environments, where slightly different aspects of their phenotype are important than had been the case in their environment of origin. Thus when I said that the just-so story I made up about proto-lungs “makes perfect sense!” I was being sarcastic only about the idea that the proto-lungs of the catfish would evolve for standard Darwinian reasons—i.e., for no reasons at all. Note that I followed up that joke by pointing out that the lungs would evolve only if there was constant selection pressure toward lungs, and that this pressure could not arise from the mere fact of the fish in its native watery environment. It can arise only because some fish gallantly challenge the limits of that environment, and of their natural equipment.
Under the Darwinian hypothesis, it is absurd to suppose that a catfish or mudskipper could “explore.” But any fool can see that it is far more absurd to suppose that a catfish or mudskipper would venture out of the water for no reason whatsoever.
Jim P. writes:
I have enjoyed this discussion, however, I must advise you that the fish in the photo is actually a spawning salmon. Its behavior in the context of the photo is less unusual than you might imagine. It appears from the background of the photo that the portion of the stream is a flat calm area. It also appears that there is some sort of run-off situation causing a great deal of water into the stream via the roadway. Spawning salmon, in an effort to swim up stream to the spawning grounds could be fooled into thinking the runoff is the source water for the stream and attempt to navigate it. I have seen salmon swim across impossibly shallow stream beds in a heroic effort to reach the spawning grounds. This appears to be the case here. I hope that doesn’t dampen the current discussion.
LA replies: Thanks for this. But how do you know it’s a salmon? Can you tell from its form in the photo? Or is it because Kristor mentioned that his friend thinks it may be a salmon?
BTW, Kristor hasn’t mentioned where the photo was taken.
Jim P. replies:
I can tell from just looking at the photo. I have fished for salmon frequently over the years in the Sacramento River system in Northern California. It is probably not a photo from California, however, because it does not appear to be a King Salmon which is what we see out here. I can also state with almost certainty that it is a male fish as well. The prominent jaw is the most distinguishing factor in the males. This looks more like a Sockeye Salmon.
I found the same photo in this blog.
LA replies:
Ok, let’s say it’s a salmon.
Now the question is, how does this change Kristor’s and my reflections, humorous or otherwise, about the meaning of it all? We can say that the salmon’s “desire” to cross the highway is a misdirected expression of its instinct to go upstream to spawn. Leaving aside the question of how the salmon’s wildly complex and improbable life cycle came into existence in the first place as a result of random mutations and natural selection (!!!), we could imagine a fish, like the salmon, that has a great instinct to go somewhere, over any obstacle. This instinct somehow keeps pushing him up onto the land. Thus commences something like the scenario I laid out in my first comment. But that scenario, as I showed, does not provide a plausible explanation of how a fish could have developed “walking” pectoral fins and ultimately develop into a terrestrial animal.
Further, it’s not just a matter of the pectoral fins becoming more muscular and so capable of propelling the fish on land. To make the transition from fish to tetrapod (four legged creature), an entirely new structure is needed, the pelvis, which holds the rear legs and supports the body in the act of walking or hopping. Fish don’t have a pelvis. How do you get a pelvis by lots of tiny changes, every one of which has to be “advantageous”? You don’t. You don’t have a pelvis—and therefore you don’t have any advantage over your non-pelvis cousins—until you have a pelvis.
By the way, this is an example of the inadequacy of the approach of intelligent design proponent Michael Behe, author of “Darwin’s Black Box.” He keeps obsessively returning to ONE example of complexity that could not result from Darwinian changes: the flagellum “motor” of the bacterium. It is an amazing thing. But there are thousands of biological innovations far less complex than the flagellum and yet still to too complex to be the result of tiny changes, the pelvis for example. By seeming at times to be hanging his whole thesis on his one pet example of irreducible complexity, he allowed the other side to turn him into something of a joke, as, indeed, happened at the Dover trial. People began to snigger when they heard for the nth time about the flagellum.
Jim P. writes:
You asked how this changes the discussion. This may be a simplistic observation, but it seems to me that the Herculean effort by the salmon to cross the road, nudged by instinct, shows not an impulse to evolve, but a desperate effort to remain unchanged, even in the face of a man made obstacle like the road.
LA replies:
Cool. LOL.
May 12
Kristor writes:
You write:
“… we could imagine a fish, like the salmon, that has a great instinct to go somewhere, over any obstacle. This instinct somehow keeps pushing him up onto the land.”
But think about this a moment. This is like saying:
“… we could imagine a mammal, like the bear, that has a great instinct to go somewhere, over any obstacle. This instinct somehow keeps pushing him to leap off the edge of extremely high cliffs.”
You see the problem? Not with you or your line of thinking (qua yours), but with the whole line of Darwinian thinking (to which we are all so accustomed that we fall into it unawares) that says, “let’s imagine a situation where members of a species commit suicide repeatedly, not for any reason, but just because they somehow have an instinct to kill themselves, and then eventually the species develops the ability to survive what would formerly have killed it.” The whole thing makes no sense. [LA replies: No. It’s the pop-Nietzschean theory of evolution: what doesn’t kill me, makes me stronger. (Joke.)] A sensible bear stays away from the edges of cliffs at almost any cost; ditto for salmon and two lane blacktops. How could Darwinian theory possibly explain the evolution in a species of an instinct to go where it will almost certainly die? But again and again, Darwinians are allowed to engage in building exactly this sort of insane scenario as a parsimonious explanation.
None of this is to argue that organisms take no risks. Clearly they do. Any innovation is a risk. But a bear doesn’t jump off a cliff unless he has a reason—a damn good reason, which is utterly clear to his simple little ursine mind. Ditto for the salmon on the highway. Risk makes sense only if one can compare the risk to the potential reward. That is, it makes sense only in the event that the risk-taker has a goal in mind (taking “mind” in the broadest sense). Innovation that is not constrained by the inbuilt teleology of the organism (what Aristotle would have called its nature) is insanely dangerous chaotic flopping around, and is bound to be lethal. This is another way of saying that it can’t last long (which, perhaps, should reassure us about the liberal prospect).
I think Jim P. is actually onto something important in characterizing the salmon’s whacked reproductive rituals as a desperate effort to maintain things the way they have been. It is a truism of evolutionary theory that most innovations are lethal. This is a restatement of the Burkean justification for the defense of tradition. One of the things organisms try to do with all their might is maintain the tradition of staying alive (that’s why liberals make unprincipled exceptions). They seek survival; they seek reproduction. These things don’t just happen by themselves, as would have to be the case if biology were truly non-teleological. No; they take immense effort, immense focus, even immense rationality and virtue (a raccoon that is not a good raccoon, and rational so far as is possible to him, will not last long). Staying alive is non-trivial. Every minute of it represents a great achievement, a triumph over the thermodynamic odds. At the same time, every moment of life is yet another climb into an unfamiliar, alien environment—the future—that is every bit as likely to be lethally problematic as what the salmon is encountering on that highway.
Finally: it is totally impressive to me that Jim P. can identify that fish as a sockeye salmon from the photograph.
LA replies:
A brief reply. I did not mean that the fish was seeking suicide. My model was the salmon, which in its unstoppable instinct to get upstream, I suggested might accidentally go in wrong directions, from time to time, like crossing a flooded highway, and so charge into places it where it shouldn’t be. My idea was simply to set up a scenario by which fish could end up out of water, and so the fish with the presumably stronger fins would survive, leading to the further evolutionary scenario in the direction of “walking fins” already discussed.
Kristor replies:
Yes, I know. It was a comment in passing that you made in setting up a larger point. I don’t disagree. But it really struck me. The sentence seems innocuous, one hardly notices it. We encounter such sentences all the time in discussions of evolutionary biology. “So the Monarch butterfly travels 8,000 miles to breed.” We take this sort of thing for granted, because it is everywhere in the biosphere. But when you look at it carefully, it just leaps out at you that Darwinism is asking us to believe that natural selection somehow rewarded such species for behavior that is insane, suicidal. It just struck me with great force that we have all these animal species that go to extraordinary lengths and take fantastic risks in order to breed, or feed, when there are alternative strategies close at hand that would be just as successful at far less cost. How is it that natural selection didn’t reward those more efficient alternatives? How is it that natural selection does not almost instantly wipe out all these ridiculous salmon who insist on returning to their spawning beds, in favor of salmon who sensibly find the nearest bed of gravel and congregate there for breeding? This sort of wild waste all of a sudden seems just ludicrous to me, a huge lacuna. [LA replies: The answer is that life is not utilitarian, as reductionist 19th century types like Darwin believed. Life is prodigal, its seeks to transcend itself. (That’s not meant to sound Nietzschean!)]
Or think of the peacock’s absurdly expensive, life-threatening display. I know, I know: sexual selection. But does it really make sense that natural selection, which ruthlessly prunes all but the most fit, should have allowed such excesses to perdure? Should not sexual selection itself have been selected against long since?
For that matter, is not life itself an absurd excess? Would it not be far more thermodynamically efficient for life to have been ruthlessly exterminated by material circumstances?
Here’s the thing. As a materialist explanation, Darwinism is committed to what is called the least path. It is an equilibrium model, under which biological systems settle naturally and without any supervision or teleology into the most thermodynamically efficient configuration. But the fundamental problem with this explanatory strategy is, first, that biological systems often display tremendous inefficiency (peacock, salmon, Monarch, human, on and on); and, second, that even the most parsimonious and efficient living systems homeostatically seek equilibria that are still quite far from thermodynamic equilibrium. It’s no good to point out that they can do this because they are running on the tremendous input of energy from the sun. The question is not how they can do this, but why they do this. Sure, life is thermodynamically possible because the sun is burning itself up, and we can survive and build negative entropy in the eddies of that vast great entropic flux. But why do we? Why is there not just a dead eddy? Wouldn’t that be a more thermodynamically efficient way of running an eddy?
Life is possible, but so is death; and, death being more thermodynamically efficient, it should everywhere prevail. This is what I was trying to get at in a conversation we had about a year ago, in saying that the problem with Darwinism is that it makes death basic. It runs on death, and nothing else. If it is true, then only dead states of affairs should have survived the scythe of natural selection.
Under a least path constraint, there is no explanation for life. The existence of the biosphere contradicts what we would expect to have discovered on planet Earth under a least path, thermodynamic equilibrium model, namely a dead planet with storms. This at least is true for the classical materialist doctrine of nature.
But once we admit final and formal causation back into our doctrine of nature, the problem goes away. If we understand the adherence of things to physical law as a goal-seeking, value-seeking activity rather than as a happenstantial agglomeration in a dead chaotic flux, then the world is re-enchanted from the bottom up. Then such sentences as, “life [and, in the final analysis, matter, nature itself] inherently contains potentialities and is driven to fulfill those potentialities,” make perfect sense. Then the problem of explaining the wild extravagance of the Monarch butterfly or the Gothic Cathedral simply goes away. Instead of being only about thermodynamic efficiency and entropy and death, the world is about all those things plus beauty, goodness, life, consciousness. Then we don’t have to ask what it is that is driving nature toward the expression of beauty: nature wants to be beautiful, because the beautiful is good.
“Want” is a word carefully chosen. It connotes both desire for the Good and privation thereof, thus indicating that impulse, essential to all created beings, toward the realization of their particular ideal contribution to the transcendent ideal for the whole created order.
I’m sure I’m not expressing this very well.
Posted by Lawrence Auster at May 11, 2009 01:37 AM | Send
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