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In a recent interview with David Klinghoffer and Michael Denton over at Evolution News and Views, author David Berlinski revealed the big question he’d like to ask Darwinists about the transition from a land-dwelling mammal to a sea-dwelling whale: “How many changes would I need?” Biochemist Larry Moran answers: “Evolutionary biologists who have spent their entire careers studying evolution, genetics, and developmental biology are comfortable with a few thousand mutations causing the transformation from land animals to whales.” And that’s not all. A mere 340 beneficial mutations would have been sufficient to transform the common ancestor of man and chimp into a human being, according to biologist Ian Musgrave of Panda’s Thumb. (That’s 240 mutations in protein-coding genes and 100 in regulatory genes.)
In case readers are wondering why I put “3,000” in my headline rather than “a few thousand,” the reason is simple. Calculations by evolutionary biologist J.B.S. Haldane (which were subsequently cited by ID proponent Walter ReMine) appear to suggest that the maximum number of beneficial mutations that could have occurred in the human lineage over 6 million years is 1,667, and if we generously allow three times as long an interval (i.e. 18 million years) for the evolution of whales (whose generation time and effective population size is not so very different from our own), then we arrive at an upper limit of 3 x 1,667 or roughly 5,000 beneficial mutations. And it’s probably less than 5,000, since the actual time available for the transition from a land animal to a fully aquatic basilosaurid whale was only nine million years, and modern whales took a further five million years to evolve, after that. The interesting thing is that although Musgrave harshly criticizes ReMine for distorting Haldane’s own interpretation of what has become known as Haldane’s dilemma, he does not dispute the notion that 1,667 is the maximum number of beneficial (as opposed to neutral) mutations that could have been fixed in the human lineage – which seems to imply that 5,000 is the maximum number that could have occurred in the lineage leading to whales. Musgrave himself thinks that a much lower number of mutations – about 340 – would have been enough to transform the common ancestor of man and chimp into a modern human being, and if we multiply the figure of 340 by 3 (allowing for the fact that it may have taken three times longer for whales to evolve than for humans to do so), then we get 1,020 (or about 1,000) as the number of mutations that would have been fixed in the whale lineage, if the rate of fixation for beneficial mutations was the same as in the human lineage (although it’s probably higher, since whales have undergone more morphological changes than humans have). The foregoing points suggest that the true number of beneficial mutations that were fixed in the whale lineage must lie somewhere between 1,000 and 5,000. Over at Professor Larry Moran’s Sandwalk blog, commenter Mikkel Rumraket Rasmussen opines that the lower figure is closer to the truth, as many mutations have impacts on not one, but multiple body organs. So that suggests that we’re looking at a ballpark figure of 3,000 beneficial mutations that got fixed in the lineage leading to whales.
Now, I’m sure that many readers are thinking that there must be something wrong with these figures. I know I did, when I first saw them. My initial response was that since a very large number of organs and biochemical systems would have had to undergo radical transformation in order for whales to evolve (as Dr. Richard Sternberg cogently argued in a recent interview), and that since a very large number of beneficial mutations would have been required for each individual organ or system to be transformed in a way suitable for aquatic life, the total number of mutations must have been very large too. But how large? My very crude back-of-the-envelope estimate was in the tens of thousands: 100 organs (or systems) times (say) 200 mutations per organ, since that’s about one-tenth as many as the 1,829 steps envisaged by Nilsson and Pelger in their widely cited model of the evolution of the eye (which I criticized here on Uncommon Descent). But my figure of 200 mutations per organs may have been too high, as Nilsson and Pelger themselves acknowledged that their estimate of the number of steps was a conservative one, and if “only” 30 mutations per organ were required during the evolution of the whale, then we obtain a total of 3,000 (= 30 x 100), which more or less agrees with Professor Moran’s estimate. Alternatively, if some mutations had a beneficial impact on two or more organs, as Sandwalk commenter Mikkel Rumraket Rasmussen suggests, then the number could be lower still – although I’m rather skeptical of the notion of a mutation that has a beneficial (as opposed to neutral) impact on multiple organs, having never read of one in the literature.
Why does the number of beneficial mutations that got fixed during whale evolution matter, anyway?
The reason why I am harping on about the number of beneficial mutations that would have been required to transform a land mammal into a whale is that Dr. David Berlinski raised the issue in a recent interview with David Klinghoffer and biochemist Michael Denton (bolding mine – VJT):
If there would be one question I’d like to pose to a serious, open-minded Darwinian biologist, it is this: how come you guys never go to the next step, which is a quantitative assessment of your claim? How come you’re always showing us nice pictures, one creature developing into the next, and all sorts of arrows connecting them – which, of course, prompts the question, “Where’d you guys find the arrows? You found the fossils, but where did you find the arrows?” That’s the kind of question I’d like to ask, and dozens of other questions along the same lines.
So, how many steps? 50,000, 3,000 or 10?
From an Intelligent Design standpoint, there are two (apparently contradictory) ways in which one could react to the proposal that 3,000 beneficial mutations were required to transform a land mammal into a whale. One way is to argue that because the differences between whales and land mammals are deep-seated differences, affecting organs in practically every part of a whale’s body (as Dr. Richard Sternberg has convincingly argued), then a very large number of steps must have been required in order to transform a land mammal into a whale. In his interview, Berlinski proposes a figure of 50,000 to 60,000 changes that would be required, humorously likening it to the problem of converting a 1954 Chevrolet Corvette into a Nautilus submarine.
The other way of reacting to the above-cited figure of 3,000 beneficial mutations is to look at the fossil record, which shows a mere ten or so intermediates between land mammals and whales, and to argue (as David Berlinski does) that even if a large proportion – say 90% – of the intermediates between land mammals and whales have been obliterated from the fossil record by “the injuries of time,” there couldn’t have been more than 100 intermediate forms – which means that the number of beneficial mutations that got fixed in the whale lineage must be much lower than 3,000. Indeed, Berlinksi, at one point during his interview, suggests that a Darwinist might argue that perhaps only “10 or 20 changes masterfully controlled by 10 or 20 genetic switches are all that are required” for the transformation. In other words, “the structure of the whale is already in the cow in terms of its potential to become a sea-going creature, but not perhaps an air-going creature.” [Although Berlinski jokes about a cow being transformed into a whale, he acknowledges elsewhere in the interview that it wasn’t a cow, but another kind of land animal, and recent research indicates that it was actually an ancestor of the modern hippopotamus.] Indeed, Berlinski thinks this is “the only conceivable answer” an evolutionist could give, if evolution is defined as “one change after the other,” via “random mutations.” He then adds: “But that, of course, pushes the problem one step back. How come the creature is set up to become a sea-going creature, if it’s spent all of its evolutionary history on the land? Where’d that come from?”
At first sight, it might appear puzzling that two different approaches to whale evolution – an anatomical approach and a paleontological approach – should yield such wildly divergent results for the number of beneficial mutations that would have been required in order for whales to evolve. But that is precisely Dr. Berlinski’s point. He thinks it illustrates a genuine paradox for any Darwinian account of whale evolution.
Berlinski’s paradox
In his interview, Dr. Berlinski puts forward the argument that generates a paradox for a Darwinian account of whale evolution, as follows (bolding is mine – VJT):
If you were to take a Chevrolet Corvette built in 1954 and decide you want to make a Nautilus Class submarine out of the thing, [and] give it to a lot of engineers – “Fellas, go do this. Do it for me” – I think it could be done, but we all have a sense of the engineering complexities. To do it would be a big, big, big project. The question I’d like to ask in all of this is: give me a quantitative estimate of how many steps would be required to change that Chevrolet Corvette built in 1954 to a Nautilus Class submarine? I don’t want you to give me a quantitatively precise answer, but I want you to give me a ballpark estimate – say, it’s off by an order of magnitude from what I’m told. And I think if we were talking about Chevrolet Corvettes and Nautilus class submarines, the answer would ballpark be: 50,000 changes, 60,000 changes, maybe 100,000 changes, if it’s feasible at all. I kind of suspect it could be done.
Now, I want the same answer for the transition from a land-dwelling creature to a sea-dwelling creature. How many changes would we need? Now why would I be interested in that number? Let’s call that number the “X” number. And this is the point that the Darwinian community never finds curious. If we knew that number, which is an accessible number – we know enough biology to grasp that number – we could compare it to the fossil record. The fossil record has about ten intermediate fossils between a land-dwelling creature and an ocean-going whale. If there are ten, let’s say the tides of time have buried another hundred – perfectly plausible. But if there are 50,000 required changes, there should also be 50,000 intermediates, according to standard Darwinian doctrine. If there is an inequality, a strong inequality between those numbers – the number of fossils that we observe, padded with the number of fossils we might have observed were it not for the injuries of time, and the number of changes – morphological, cellular, biological, physiological, anatomical – that are required to make that transition, then we could assess the plausibility of what is one of the most interesting Darwinian sequences in the record. That’s never done. That’s just never done. No Darwinian paleontologist has ever said: “We expect there to be 50,000 sequences in the whale transition sequence, because we’ve computed the number of changes that are required. But wouldn’t you think, Darwinian fellow-seekers, that that’s an obvious first step to take in making your scientific claims quantitative – not rigorously quantitative, but ballpark quantitative? It’s not done.
How convincing is Dr. Berlinski’s argument?
Now, I’d like to declare up-front that I think that whale evolution constitutes an excellent argument for Intelligent Design: it had to have been carefully coordinated, controlled and supervised. If you’d like to know why, try listening to this. Having said that, however, I don’t think that Dr. Berlinski’s argument would cause any discomfort to a modern-day evolutionist. In fact, I think it’s flawed on three counts.
First, Dr. Berlinski defines evolution as “one change after the other,” via “random mutations” (8:36). He appears to be laboring under the misconception that evolution proceeds by beneficial mutations being fixed sequentially, one after another, with the entire population having to acquire each mutation before the next one can occur (h/t lutesuite of Sandwalk). In reality, Darwinists (and for that matter, mutationists like Professor Larry Moran) envisage the evolution of the whale as involving lots of mutations occurring in parallel, in various organs and systems in their bodies.
Second, Dr. Berlinski’s contention that the number of fossil intermediates in whale evolution should roughly equal the number of changes required to make the transition is incorrect, because in the first place, if the changes are occurring in parallel, then the number of changes will exceed the number of fossil intermediates by at least a factor N, where N is the number of organs and/or biochemical systems in a whale’s body that are undergoing transformation; and in the second place, a single beneficial mutation occurring in a whale’s body would not be enough to transform it into a new fossil species; and finally, most of the beneficial mutations that would have occurred involved internal organs rather than changes to whales’ skeletons, and hence wouldn’t show up in the fossil record anyway. Hence it would not be at all surprising if the number of changes required to transform a land mammal into a whale turned out to be several orders of magnitude larger than the number of steps observed in the fossil record.
Third, the notion that a mere “10 or 20 changes masterfully controlled by 10 or 20 genetic switches are all that are required” is so fanciful that not even a Darwinist would seriously propose it, and no Darwinist, to the best of my knowledge, has ever done so. Instead, as we’ve seen, the consensus figure, as reported by Professor Larry Moran, is “a few thousand.”
I wholeheartedly endorse Dr. Berlinski’s demand that Darwinists – and indeed, evolutionists of any stripe – should be asked to provide a quantitative assessment of their claims.
However, I am forced to conclude that the Darwinian scenario for whale evolution won’t be overturned simply by calculating the number of morphological and physiological changes that would have been required. We have to employ a different approach.
So, what are the best ways to show that the evolution of the whale must have been intelligently designed? That’s a topic I’ll address in my next post. In the meantime, I’d like to throw the discussion open to readers. How many beneficial mutations do you think were required in order to transform a land mammal into a whale, and can you explain why nine million years would not have been long enough for the process, if evolution is regarded as an unguided process?
(The picture at the top shows a humpback whale breaching. Image courtesy of Whit Welles and Wikipedia.)