dying in agony

Ever wonder why so many fossilized animals, particularly dinosaurs, look so twisted about when they're found? For much of my life the explanations been that ligament drying caused those seemingly agonized positions. That long held theory has recently been revisited by Cynthia Marshall Faux, a veterinarian and paleontologist from Museum of the Rockies, and her co-author Kevin Padian, a professor of integrative biology at the University of California, Berkeley.

In the March issue of the quarterly journal Paleobiology the article so fetchingly titled "Agonized Death Throes Probable Cause Of Open-mouthed, Head-back Pose Of Many Dinosaur Fossils" explores the problems with the ligament drying theory. Rather, they postulate, the agonized looking positions are exactly what they seem. The result of an agonizing death. Hmmm. Common sense wins out in the end!

Witness the Archaeopteryx over there on the left. Just by looking at the position of the bones you get the distinct impression of a long painful death. The authors of the paper mentioned previously hypothesize that the dinosaurs died in this posture as a result of damage to the central nervous system. In fact, the posture is well known to neurologists as opisthotonus and is due to damage to the cerebellum, a part of the brain. In humans, cerebellar damage can result from suffocation, meningitis, tetanus or poisoning, and typically accompanies a long, slow death.

I found reading this report very interesting because it illuminated some peculiar ways of thinking that I think are common in people. On the one hand, I always enjoyed explaining to others that while the dinosaur fossils looked like the animal was in agony, it was really just an artifact of how the tendons, muscles, and ligaments dried. That is, I liked having specialized knowledge that others didn't have. Now that this report comes out bursting that whole theory, I still find an enjoyment in the new paradigm. This time because a "common sense" theory blows a more convoluted one out of the water.

It's amusing to me to find both quite different reactions within me to the differing interpretation of one set of fossils over time. The mind is a peculiar place.

Brian Switek, over at Laelaps, wrote an excellent essay on this death throes paper--focusing on the opisthotonus aspect but giving a lot more history. I hadn't read his post before I wrote this one--and now I'm feeling woefully inadequate. If you're interested in science, Laelaps is a well written and very interesting blog.