Famous First Words #11: Dinosaur Extinction -- Luis Alverez et al.

Famous First Words is a recurring LabKitty feature in which we have a gander at the opening line of an historic scientific article. I then take the liberty of "punching it up," as we say in the blogging biz.

What killed the dinosaurs?

That simple question created one of the most acrimonious debates science ever witnessed. I shan't get into the sordid details here (a wonderful telling can be found in Bill Bryson's A Short History of Nearly Everything, which you should buy and read immediately, for the dino story and everything else) but here's the short version: It had been long known that dinosaurs -- after dominating the planet for millions of years -- disappeared suddenly.

Many explanations were proposed -- volcanic activity, overpopulation, cigarette smoking -- but none fit the available data, the most perplexing of which was a thin layer of iridium-rich sediment in the rock strata where dino fossils ended. Iridium is not found much on Earth, but it is found lots in asteroids. Earth gets hit by asteroids all the time; usually they're smallish (go outside at night, look up, and wait) but sometimes they're anything but. It's not divine retribution, it's gravity. It's what big floaty rocks do. And they're out there in the millions.

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Alverez, a physicist, and his son Walter, a geologist, get to thinking about the iridium, and the rocks, and with a little serendipity (and some help from chemists Frank Asaro and Helen Vaughn Michel) identified an impact site sufficiently large and correctly ancient that supported their explanation: Dinos were hanging out, doing dino stuff, when a BFR came down and clobbered the bejezus out of them (it hit off the coast of Yucatan, where LabKitty once snorkeled, but could not partake in the unlicensed scuba on the down low because of childhood ear tubes). The impact threw up smoke and ash across the globe, and much else besides. Big stompy animals like dinosaurs didn't fare well in the new normal, whereas little scurrying critters did.

Long story short: evolve, evolve, evolve, Bob's your uncle, and a few million years later some Homo Sapiens pieced together the whole chain of events and wrote a paper about it. Here's how that paper began:

Extraterrestrial cause for the Cretaceous–Tertiary extinction
Science, 208:1095-1108 (1980)

Platinum metals are depleted in the earth's crust relative to their cosmic abundance; concentrations of these elements in deep-sea sediments may thus indicate influxes of extraterrestrial material.

Factual enough, I suppose, but not really an opening that gets your fur puffy. If it were me, I would have started off a bit more dramatically. Here, try this:

Extraterrestrial cause for the Cretaceous–Tertiary extinction
Science, 208:1095-1108 (1980)

A screaming comes across the sky, a gaping hole slashed in the firmament by an iridium-rich harbinger of doom on its way to a rendezvous with destiny that will instantly vaporize everything within a thousand kilometers of the Yucatan. Far away on the effluvial plains of North America, a Tyrannosaurus is munching on some tasty trilobites, awkwardly scooping them from a vestigial pond using his comically-small arms. The ground shakes, the brackish water rocks and sloshes. A youngling peers out from under his massive form. "Papa, qu'est ce que c'est?" it asks. The reigning king of the beasts looks to the south and studies the churning darkness approaching fast on the horizon. "Je ne sais pas, mon cher," he answers. "Je ne sais pas."

See? Really sucks in the reader. Why dinosaurs are speaking French is an issue I really don't want to get into right now.