Heliophage


David Raup, RIP
July 16, 2015, 5:15 pm
Filed under: By, Eating the Sun | Excerpts, etc, with or from EtS

The great palaeontologist Dave Raup has died: here’s the NYT obit:

An audacious theorist widely viewed as among the most singular thinkers in his field — Stephen Jay Gould once referred to him as “the world’s most brilliant paleontologist” — he made his mark in the computer laboratory and in published works rather than in the literal dust of history.

He never dug up a dinosaur and was the first president of the Paleontological Society, an international professional association founded more than a century ago, never to have formally described a new species in the scientific literature. His ideas, however, helped transform the study of the history of life on earth.

I met him pretty early on in my career, and found him fascinating and generous with his time. He’s in part responsible for my subsequent fascination with asteroid impacts. There’s an account of my first encounter with him in Eating the Sun: I’ll paste it below.

But first a little detail that I found fascinating. To me in the 1980s, Raup was immensely forward looking, breaking the bounds of what palaeontology could be. But he was also, in his time, stubbornly resistant to change. I remember him telling me that he rejected plate tectonics well into the 1970s, shocking students by showing them the famous Bullard Fit — a recreation of the Earth without the Atlantic, showing how well Africa and South America fit together — and then showing them a fit of his own devising that looked just as good — but had Africa upside down.

I don’t know the details of his dubiousness about  plate tectonics; I wish I did. They would have been highly unusual, I think, for a palaeontologist; as Naomi Oreskes’ brilliant “The Rejection of Continental Drift” points out, palaeontologists were well disposed towards believing in continental drift pre plate tectonics. The fact that, as had been the case with Kelvin and the age of the Earth, the people looking at fossils had been right and the physicists (whose arguments weighed most heavily in the pre-plate-tectonic rejection of continental drift) had been wrong has since then been one that palaeontologists have been happy to crow about whenever they are accused of being “mere stamp collectors”.

But while not understanding its basis, the very fact of Raup’s doubt in the matter seems to me to speak well of him. He was not just sceptical about the status quo. He was sceptical about the most successful overthrowing of a status quo in the history of his science. If he had just been someone who enjoyed seeing orthodoxy stood on its head he would have embraced plate tectonics straight away; coming of scientific age, as he did, in the 1960s, if he had been a mere contrarian, or a young man in a hurry, nothing would have been more natural than to have joined the storming of the barricades. But he was somehow unconvinced. And so he lined up with the conservatives and refuseniks.

More simply: he could be right big time; he could be wrong big time.

Anyway, my condolences to his wife, his colleagues, and his pupils. Continue below the break for the extract from Eating the Sun.

Chapter Five: Fossils

The rock garden held her attention for some time. She tried to watch the rocks grow, and failed as always, but did not mind failing in such a beautiful place . — Spider Robinson, “Night of Power”

Towards the end of 1988, in a slightly dilapidated Mini, Bob Spicer, Andy Knoll and I inched our way through the snarled traffic of a southeast London Saturday to Down House, the home of Charles Darwin. Andy, then and now a Harvard professor, had never visited it, and wanted to make a pilgrimage. Bob, then teaching at Goldsmith’s College in nearby Deptford, but later to be in charge of a large amount of the earth and planetary science research at Britain’s Open University, was being obliging. I, who had met them both at a meeting on extinctions in the fossil record held at the Royal Society over the previous week, had opportunistically wangled an invitation to come along.

That meeting at the Royal Society, Britain’s oldest scientific organisation, had been an education for me. It had mostly consisted of Britain’s older generation of palaeontologists being rude to an eminent American during the presentations, while in the coffee breaks their younger colleagues reassured him that not all Britons were blinkered and boorish. The eminent American was David Raup of the University of Chicago, who had in the mid 1980s suggested that the mass extinctions which had punctuated the fossil record ever since complex animals first appeared—which is to say, for a bit more than half a billion years—could have been caused by comets.

The starting point of Raup’s argument was increasingly strong, if contested, evidence that the mass extinction which killed off the dinosaurs at the end of the Cretaceous, 65 million years ago, had been caused by the impact of a comet or asteroid. Luis Alvarez, the man who had come ashen faced into one of Andy Benson’s physics lectures to proclaim the news of nuclear fission, and his son Walter, a palaeontologist, had discovered high levels of iridium in sediments laid down right at the relevant time. Since iridium is rare on earth the Alavareses suggested these deposits were fallout from a massive comet or asteroid impact which had thrown up enough dust to shut down photosynthesis all around the world; half the earth’s species then starved in the dark.

Raup and his colleague Jack Sepkoski had taken the idea further, suggesting all mass extinctions were caused by such collisions, and that they come about on a regular basis because of a supply of impacting comets regulated by a slow astronomical cycle. This was all too much for the upper echelons of British palaeontology. They had been schooled to believe that geological explanations should always be gradualist, not catastrophic. The one great paradigm shift they had lived through—the advent of plate tectonics—had reinforced this view. Even as it provoked a sudden shift in the way the world was seen, plate tectonics denied the need for sudden shifts in the way the world behaved. Continents moving around the globe slowly and sedately since time immemorial could explain pretty much everything. What’s more, I realised as the meeting went on, this establishment was suspicious of grand theory in all its forms. It suspected that such theorising involved a lot of input from other sciences—which it seemed somewhat dubious of—and insufficient time spent doing fieldwork in often rainy conditions, an activity which should clearly be the core of the discipline. Thus the hostility to Raup, spiced with such barbs as “This slide, I should explain for our American colleagues, shows what we call a rock”.

For me, and for many, the first of the supposed flaws in Raup’s approach was a large part of its attraction. When he looked at the shell of an ammonite, he saw more than the details of where it was collected and the ways in which it differed from the shells of other ammonites. He was willing to put the study of fossils, often seen as a form of mere stamp collecting, into the widest of contexts, linking events separated by hundreds of millions of years, tying the deaths of invertebrates on muddy seafloors to cometary encounters on the edge of the solar system. He was convinced that there could be grand truths and over-arching patterns to the history of the world, truths that cut across the narrow lines of academic disciplines. And he was convinced that fossils, looked at properly, might reveal them.

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