Laws of correlation and the derivation of evolutionary patterns from developmental rules

Cuvier, and his British counterpart, Richard Owen, had an argument against evolution that you don’t hear very often anymore. Cuvier called it the laws of correlation, and it was the idea that organisms were fixed and integrated wholes in which every character had a predetermined value set by all the other characters present.

In a word, the form of the tooth involves that of the condyle; that of the shoulder-blade; that of the claws: just as the equation of a curve involves all its properties. And just as by taking each property separately, and making it the base of a separate equation, we should obtain both the ordinary equation and all other properties whatsoever which it possesses; so, in the same way, the claw, the scapula, the condyle, the femur, and all the other bones taken separately, will give the tooth, or one another; and by commencing with any one, he who had a rational conception of the laws of the organic economy, could reconstruct the whole animal.

Cuvier famously (and incorrectly) argued that he could derive the whole of the form of an animal from a single part, and that this unity of form meant that species were necessarily fixed. An organism was like a complex, multi-part equation that used only a single variable: you plugged a parameter like ‘ocelot’ into the Great Formula, and all the parts and pieces emerged without fail; plug in a different parameter, say ‘elephant’, and all the attributes of an elephant would be expressed. By looking at one element, such as the foot, you could determine whether you were looking at an elephant or an ocelot, and thereby derive the rest of the animal.

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Young master Darwin

Tristero makes a few points that are exactly what I’ve been trying to get across in my introductory biology class this week, where we’re covering Charles Darwin and the evidence for evolution. The first is that we do not rely on Darwin’s authority; there is no cult of personality, no reliance on the master’s word, no simple trust of anything or anyone. The other, though, is that Darwin is still a fascinating and important figure, and it’s not just that he was an old guy with a white beard who lectured the law.

Darwin’s not a stuff-shirted Nigel Bruce pip-pipping his way across the Empire. He is a young kid on a ship who once had the gall to grab a sailor’s dinner from his plate because he (the sailor) was about to eat a very rare ostrich Darwin had been searching for in vain for months. He’s a fellow who, when learning to use the bolas from Argentinian gauchos, managed to lasso his own horse, and he’s willing to write about it. Later, as he worked through his theory, which took him over 20 years to announce, he was tormented by the implications if it was misconstrued (as it was, right from the beginning). He developed a cautious style that is a model of arguing and inferring from the evidence. And, by all accounts, Darwin was a man devoted to his family and friends, deeply considerate and generous.

Yes, Darwin had his faults. But anyone with ten times his faults and one tenth of his talent would easily win a Nobel or Macarthur. That kids don’t have a chance to learn who this guy was – that’s a real crime.

One thing I tried to get across to my students was how much he was like them. He went off to Cambridge when he was about their age, and on graduation, a position they’ll all be in in a few years, had to wheedle his father into letting him go on this exotic sea voyage instead of settling down. Darwin really was a young fellow when he went off on the Beagle, in his early twenties.

Despite his charming youth, though, I still have to explain the list of things he got right and the list of things he got wrong. It’s the evidence and the ideas that matter, not the lovely personality behind them.

The hollow man

Yowza. Vox Day tried to pull his usual ahistorical, illiterate, ignorant schtick, blaming Nazis and Communists on ol’ Chuck Darwin, and Ed Darrell completely eviscerated him. I mean, it’s like all that’s left of Day is a few tattered scraps of skin hanging from a stick, drying in the wind.

Vox Day is a rather cheap and easy target, I know, but still … it’s frightening to see. It’s so thorough.

Down House proposal withdrawn

Darwin’s home was going to be submitted to UNESCO’s World Heritage committee for designation as a World Heritage site, but that application was withdrawn, to be resubmitted in two years after some reworking. Down House has some handicaps compared to other World Heritage sites:

But without natural wonders or spectacular architecture, Darwin at Downe does not tick obvious World Heritage boxes. Although he was surprised to hear of Downe’s difficulties, Geoffrey Belcher, site coordinator for the Maritime Greenwich World Heritage Site in London, thinks that “A site with a limited range of qualities will be at a disadvantage.” The inclusion of the Royal Observatory makes Greenwich one of the few World Heritage Sites to celebrate science, but the site boasts architectural splendour and naval history too.

It is a rather different site—it’s not famous for some major chunk of tangible real estate, something that visitors could touch and take photos of, but for being a place where one of the major thinkers of the 19th century did his research and writing and correspondence, a kind of locus of thought. It’s definitely an important place in the history of science.

Ian Robinson finds one unfortunate comment in the article—a comparison with religious sites. Bleh.

“I can’t think of anything more important to do for the history of nineteenth-century science than to protect the whole environment Darwin inhabited and exploited,” says James Moore, a Darwin scholar at the Open University in Milton Keynes and one of the first historians to explore the importance of this rural refuge to Darwin. “Muslims go to Mecca, Christians go to Jerusalem, Darwinians go to Downe,” he says.

That’s putting the wrong spin on it. Another World Heritage site is Independence Hall in Philadelphia; we don’t go there because we worship the declaration of independence, or because we think the founding fathers were gods (OK, some people do, but they’re insane). Another is the Olympic National Park—again, it’s not a holy place, it’s a natural wonder. I like both, but that doesn’t make me an Independencehallian or an Olympian…although the latter does have a nice ring to it.

Nicholls H (2007) Darwin down but not out. Nature, 20 June 2007, doi:10.1038/447896a

They were only athier, we’re the athiest!

Historical perspective certainly does change one’s views of our current little struggle with theism. Kieran Healy identifies the original atheists—those horrible people who were defying cultural mores and denying the traditional deities.

It was those uppity Christians.

Matters were very different with the Christians, who had ex hypothesi abandoned their ancestral religions … The Christians asserted openly either that the pagan gods did not exist at all or that they were malevolent demons. Not only did they themselves refuse to take part in pagan religious rites: they would not even recognize that others ought to do so. As a result … the mass of pagans were naturally apprehensive that the gods would vent their wrath at this dishonour not upon the Christians alone but on the whole community; and when disasters did occur they were only too likely to fasten the blame on to the Christians.

So, if they had a poll around 250AD, the most untrustworthy group in the Empire would have been those Christians? At least this is a historical example that shows the atheists can take over! Let’s just be sure we don’t make the mistake the Christians did.

Part of Ste. Croix’s larger argument is that pretty soon the boot was on the other foot, the persecuted became enthusiastic persecutors.

Bad history does not mean bad science

An article titled “Darwin misconceptions in textbooks slammed in biology journal” sure sounds like it ought to be a hard-hitting criticism—we ought to look into that. Larry Moran did, and wow, what a bust. It’s pathetic. It’s a list of seven “errors” made in discussions of Darwin’s biography in textbooks, which is little more than a lot of nit-picking over details that are not so important to a biologist, but are more a matter of historical accuracy. Some of them are trivial matters of emphasis—saying that Darwin published the Origin after he returned to England is quite correct, and unless they’re discussing what he did afterwards, saying that he waited 23 years to publish is irrelevant in the context of a biology textbook—and others, such as the statement that Wallace and Darwin presented their work together when both were presented in absentia are plain wrong, but again, do not affect the substance of the science. I agree that if they’re going to present that material, they ought to get it right…but I also wouldn’t object to stripping out all mention of Darwin’s name (except in the bibliography), and focusing on the evidence and experiment and theory. It’s not that I think the history is unimportant, but we’re already tightly strapped for time to cover the essentials in introductory biology; let’s set it aside in class, and instead tell the students to go read Janet Browne or Desmond and Moore in their copious free time.

I can sympathize with an expert insisting on holding textbooks to a better standard, and in that sense this is a reasonable work. However, it’s being pushed by hack journalist Denyse O’Leary and the British propaganda site “Truth in Science” as if it is a challenge to the science. It isn’t. It’s a criticism of lazy text book publishers, and that’s about it. Except when creationists distort a criticism of historical reporting into another reason to cast doubt on a science.