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Monday, November 03, 2008

In Search of Spandrels

While looking for postings on the Maynard Smith fumble (Maynard Smith on Stephen Jay Gould) I came across this one, posted on on Aug. 20, 1998. I had forgotten about my second search for the Spandrels paper.

This is a paper that every student of evolution should read. I can't think of a paper by Maynard Smith that falls into that category.
I recently found myself in the catacombs of the library archive far away from the stress of students writing their summer exams. It was very peaceful. It was also a place where creationists never go.

I must confess that my primary motivation for being there was work avoidance - I hate marking exams - but there was another reason as well. My secondary mission was to retrieve a pristine copy of the "Spandrels" paper so I could hand it out to my students. (My own copy had some embarassing margin notes that weren't fit for young eyes.)

There were many bound volumes of the Proceedings of the Royal Society of London (Series B). Did you know that this journal goes back over one hundred years? (That's even before I was born.) Did you know that you have to look in the stacks under "R", for "Royal", and not "P", for "Proceedings"? Did you ever wonder why librarians do that? My own theory is that they really don't want us to take out their books so they make it as difficult as possible to find something.

I was looking for volume 205 (1979). As usual, it was on the bottom shelf; way down at the level of my shoes. I had to get down on one knee and that's a lot of work. But at least volume 205 wasn't missing. With trembling hands I flipped the pages looking for the sacred text. Would it be there or would the pages have been cut out with a razor blade? Chances were good - pre-med students don't read about evolution.

Yes! There it was: "The Spandrels of San Marco and the Panglossian paradigm: a critique of the adaptionist programme" by S.J. Gould and R.C. Lewontin. They even spelled "programme" correctly! Off I went to the photocopy machine. Off I went to buy a new photocopy card. Back I came to the photocopy machine. Let's see now ... how much magnification will I need to fill an 8x11 page so I don't have to close the damn lid every time I copy a page? 125% should do it. Wrrrrr .... flash .... swish .... splat.

Maybe 120% would work ...

At last, page 598 was perfect. (Anyone want extra copies of the references from this paper?) I worked my way forward to page 581 fending off the librarian who insisted that I had to close the lid or I would ruin the photocopier - and my eyes (I'm not sure which was more important to her).

I was lucky there were three or four students to distract her. Behind my back I heard some mumblings about "eccentric" and "stubborn" but unfortunately I couldn't see exactly what was going on.

Hope I didn't miss anything interesting.

I knew that Gould had presented the paper at a meeting in London in December, 1978. Lewontin wasn't there because you have to fly to get to England and Lewontin thinks that if humans were made to fly then we would have evolved wings. So, who else was at the meeting? Did they publish papers in the same issue of the journal? Let's see ...

My thoughts were interrupted by some shouting in the line behind me. Guess I'd better get away from the photocopier. The machine seems to be making people angry.

Off I went to find a desk to sit down at. Found one. Off I went to the photocopier to retrieve my photocopy card. Back I came to the desk.

Someone was there. Found another desk. It had a banana peel on it.

Cool. All the papers are here. The meeting was called "The Evolution of Adaptation by Natural Selection" and it was organized by John Maynard Smith and R. Holliday. Orgel has a paper on evolution in vitro. The Charlesworths write about sex in plants. There's a paper by Maynard Smith on game theory and the evolution of behaviour. George Williams was present (more about him later). And guess who else? - Richard Dawkins!

The Dawkins' paper is titled "Arms races between and within species" (R. Dawkins and J.R. Krebs). It goes on and on about the adaptive significance of arms races and the optimization of animals. I bet the Gould talk was not well received by Dawkins in 1978. :-)

The Williams paper is very interesting ("The question of adaptive sex ratio in outcrossed vertebrates"). He examines two popular theories of the adaptive control of sex ratio (why there are 50% males and 50% females). After looking at the detailed models and the available data he concludes,
Evidence from vertebrates is unfavourable to either theory and supports, instead, a non-adaptive model, the purely random (Mendelian) determination of sex.
Good for him. I wish I could have been at the meeting. Maybe there was a discussion. Flipping to the back of the book I find a petulant summary of the meeting written by A.J. Cain. You can tell he's really annoyed at something that went on in the meeting,
Ever since natural selection appeared on the scene, there have been those who voiced an a priori and dogmatic dislike of it. One classic example is George Bernard Shaw ... I suspect from my own work that natural selection may have been very much more important than anyone has realized up to now. If so, can these emotional and other rejections of it, or, more generally, the tendency of the human race to take a non-objective view of evolution and kindred topics, be explained by natural selection?

There is a possible evolutionary explanation, as yet untested, and no other scientific one that I know of.
Whew! The discussion must have been exciting. Let's see, it should be right at the end. Ah, here it is,
[It has not been possible to include the general discussion in this publication.]

Gotta go, the banana peel is making me ill - it looks like it's been here since the day before yesterday. Is that a fruit fly? Off I go.

Back again. (Forgot my pen.) See ya.

Larry Moran


John S. Wilkins said...

You missed a perfectly good opportunity to do some fruit fly research. Are you sure you're a real scientist?

Anonymous said...

Lewontin has attended at least one meeting in Britain, so he might sometimes get into an aeroplane - or get there by ship.
Actual successful studies of natural selection were still rare in 1979, despite all talk about it. Today, more good examples exist (Kingsolver has a list), though loose talk about 'adaptation' is still prevalent, especially in molecular evolution. Why is a surfeit of non-synonymous substitutions any indication of selection, and even worse, adaptation?

derele said...

What about the Mayrs reponse"How to carry out the adaptationist program?"? I like it...

Anonymous said...

Maynard Smith is on a short list of biologists who p*** me off (along with Leda Cosmides. Incidentally, fo all our differences, R. Dawkins isn't on that list because he can control his anger.

Anonymous said...

In 1978, nobody in the US had published a well documented study of natural selection in the wild, if any study of selection in the wild at all. British researchers, amongst them Arthur Cain, had studied the mechanisms of selection in detail on wild organisms in relation to their ecology. Neither Gould nor Lewontin had studied natural selection. Lewontin had written in 1974:“… the British school (of evolutionists) carries on the genteel upper-middle-class tradition of fascination with snails and butterflies” , a remark he has not been thanked for by the British school.
So when in 1979 Gould presented a paper by him and Lewontin, in Britain, warning not to speak too easily about adaptation and selection, at least part of his audience knew much more about how to study natural selection and adaptation than Gould did. Any such warning was not necessary to that audience: that audience perfectly well knew the point. Cain might well have been not very pleased to be told about good research practice, on the implied understanding it was not being followed, while he had done the actual work, and Gould and Lewontin had not even tried.

Perhaps Larry Moran might explain to younger people who A.J. Cain is?

Larry Moran said...

Heleen says,

So when in 1979 Gould presented a paper by him and Lewontin, in Britain, warning not to speak too easily about adaptation and selection, at least part of his audience knew much more about how to study natural selection and adaptation than Gould did. Any such warning was not necessary to that audience: that audience perfectly well knew the point.

I'm sorry but that's just not correct. Most of the audience carried on as adaptationists as though they had never even read (or heard) the Spandrels paper. Richard Dawkins and John Maynard Smith are perfect examples.

Heleen, nobody ever said that natural selection isn't a potent force in evolution. That's not the point. The point—or more correctly one of the points—is that there are other mechanisms of evolution that weren't discovered by field biologists looking for adaptations.

Lewontin had published evidence for the prevalence of random genetic drift and Gould had published evidence that the fossil record wasn't consistent with slow gradual change. The talk was supposed to be a wake up call to the traditional British field biologists (snails and butterflies) that there was more to evolution than they realized.

Unfortunately, not so many woke up. And that's still true today.

Heleen, do you agree that the dominant mechanism of evolution is random genetic drift? Do you agree that it should be the default option in all field work?