Everything You Need To Know About Haldane’s Dilemma

2008.06.22   prev     next

Can I convince you that Haldane’s Dilemma is a serious, possibly fatal problem for Darwinian evolution, with an article that contains no equations, numbers, or biological examples, and can be consumed in five minutes? Read on and find out:

In the 1950s, an evolutionary geneticist named J. B. S. Haldane, who was already well-known for his work in evolutionary genetics, thought of an idea. Species do not have infinite reproductive capacity, and so this must place some limit on how fast they can evolve. Probably no reasonable person would disagree with such a statement — but it’s too vague to be scientifically useful. So Haldane, as a scientist is wont to do, decided to quantify that vague truism into a mathematical model that could be used to analyze actual data from the biological field.

So he did. But when he started plugging data about known evolutionary transitions into his formula, he got disturbing results. Each time he tried it, the formula seemed to say that the reproductive capacity of the species was not even a small fraction of what it would need to be to plausibly support the changes represented by the transition, in the time in which that transition occurred. Haldane’s model is unconcerned with the likelihood of the right mutations arriving at the right time — that’s a whole separate issue — rather, his model shows that even if the right mutations arrive in the right order, the species does not have the reproductive capacity to propagate those mutations throughout its population in the time available. The problem today is known as “Haldane’s Dilemma.”

Predictably, anti-evolutionists of all stripes have used Haldane’s Dilemma as a talking point ever since Haldane went public with it. And evolutionists have offered up various reasons to believe that Haldane’s model is flawed and therefore is not a problem for evolution. How is a curious, uncommitted bystander to know who’s right?

I once heard a story about a Japanese businessman who, during the latter phase of World War II, bought up interests that would be particularly valuable if Japan lost the war, and as a result became a very wealthy man in the post-war period. Many years later he was being interviewed, and was asked, “How did you know that Japan was going to lose the war? You weren’t an expert in any of the relevant specialties, and you had nothing to go on but the Japanese media’s reports of great victories in the Pacific. We all thought Japan would surely win. Why did you think the opposite?”

To which the businessman replied, “I simply noticed that all those great victories had something in common — they were progressively closer and closer to Japan, and farther and farther from America.”

Now suppose I’m a scientist. And I have read about Haldane’s model and understand it fully. And I know exactly what’s wrong with it. What will I do — tell everyone about the flaw in Haldane’s model? No, not yet! First, I will make a corrected model. That should be a piece of cake. Then, I’ll plug data about evolutionary transitions into my corrected model, just as Haldane did with his, but this time I will get results that show there is no problem with evolution after all. Then I will go public with it, and be super-famous as the one who finally put Haldane’s Dilemma to bed once and for all.

My corrected model, and its evolution-friendly application to empirical data, certainly will not be hidden away in some obscure science journal. It will be trumpeted all over the internet from a dozen, highly-ranked, pro-evolution websites. A quick Google search on Haldane’s Dilemma will find descriptions of my corrected model, and examples of its application, in the first page of search results.

But if you do a Google search today on Haldane’s Dilemma, you don’t find anything like that. Yes, you find lots of pro-evolution pages detailing why Haldane’s model is flawed and therefore does not refute evolution. But none of them are of the corrected-model-plus-successful-application form described above. Instead, they’re all of this form: Here’s Haldane’s model. Here’s what’s wrong with Haldane’s model. The End. Case closed. Subject terminated. Forget about it.

What can this mean? One of two things.

Either (a) Haldane, in the 1950s, was the first and last scientist who had any interest in quantifying the limits placed on evolution by the finite reproductive capacity of species, and ever since Haldane the field of evolutionary science has degenerated into nothing but a campaign to convince everyone that evolution is true, by any means necessary.

Or (b) evolutionary scientists haven’t made a corrected model because they can’t. Because they don’t really know what’s wrong with Haldane’s model.

Because nothing’s wrong with it.