There’s been a lot of controversy among people who worry about these things as to what exactly killed off the dinosaurs 65 million years ago. Was the Cretaceous-Tertiary (K-T) extinction caused by that whopping great asteroid strike in the Gulf of Mexico, or was it a result of increased volcanic activity? Both could have caused the ‘nuclear winter’ conditions that led to the demise of the big guys, and just about most else.
In true scientific fashion, the wrangling has rumbled on, but now the answer seems to have been determined. Not too oddly, the answer seems to be both.
Paul Renne and his fellow pointyheads at the University of California examined ancient lava flows in an area called the Deccan Traps in northern India. These flows are from a range of supervolcanoes, and if you take a gander at the map you’ll see that some of the flows exceed 1500 km. I imagine that would make things rather noisy, and very hot.
A bit of a close look reveals that the asteroid strike seems to have affected the subterranean plumbing and the Traps went mental. This huge amount of volcanic activity, and the crap thrown up by the asteroid strike itself, worked together. ‘It becomes somewhat artificial to distinguish between them as killing mechanisms…. It is impossible to ascribe actual atmospheric effects to one or the other.’ He then helpfully decoded his message. ‘They both happened at the same time.’ That’s useful to know, eh?
Back in the 70s there was a really wildhaired theory that gained quite a bit of traction. Whatever happened didn’t kill the dinosaurs, but it had a radical effect on the climate, and this had a disproportionate effect on the group of plants known as cycads. These were the dinos’ staple diet, but the big guys didn’t starve. Oh no. Cycads are very oily, and some idiot suggested that the dinosaurs died of chronic constipation when the oil supply failed.
Now that’s what I call a scientific theory.