Thursday, March 6, 2008

Good Gracious, My Meal is a Theropod! (Part 1 of 3)

Even if you despise science, and hate palaeontology with special fervour, you have probably noticed that these days, pretty much everyone accepts that birds descended from dinosaurs. You may have also noticed that a large number of theropods are now regularly depicted with feathers. You probably looked at your calendar realized that it wasn’t April Fools Day, and wondered what was going on. How did this epiphany come about?

Our story starts very close to Darwin, as these stories have a nasty habit of doing. It starts with Thomas Huxley, Darwin’s famous “Bulldog,” who, after a long day of puzzling over a strange dinosaur bone (located under the tibia), went home to a dinner of tender, delectable quail.

Take a moment to imagine his shock when he noticed that his repast had the same, strange bone underneath the tibia as the dinosaur he’d been studying, which turned out to be the anklebone. Huxley then theorized that birds descended from dinosaurs.

It is a great story, but like most great stories, it probably isn’t true. Archaeopteryx, the famous “first bird,” was discovered in 1861, and was immediately suspected to be a link between birds and dinosaurs. However, it was purchased in 1862 by the British Museum of Natural History. Richard Owen, superintendent of the museum, and fervent opponent of evolution, was keen to get his hands on it and put his own, anti-Darwinist spin on the find. He concluded it was simply an “ancient, long-tailed bird.”

Thomas Huxley, however, wasn’t convinced. Between 1862 and 1867, he researched living birds, and published, in 1867, a complete reclassification of birds, which alleged a reptile-bird link (On the Classification of Birds; and on the Taxonomic Value of the Modifications of Certain of the Cranial Bones Observable in That Class). We don’t know when (or if) the “quail” incident actually happened. But, it’s nice to think that the lowly quail had at least something to do with it.

What is clear is that, later on in 1867, Huxley was shown the misidentified hip bone of a Megalosaurus, and, upon correctly placing it, was struck by its similarities with living birds that he had studied. Any doubt about the tenuous connections he had drawn in On the Classification of Birds was washed away.

In 1868 Huxley gave a lecture at the Royal Institution about archaeopteryx. In a single talk, he demonstrated the link between dinosaurs and birds, and tore Richard Owen’s “ancient bird” theory to shreds.

It should be noted that Huxley was not alone in supporting this theory. Othniel Marsh, of Bone Wars fame, was also an early proponent of the dinosaur-bird connection. Marsh also was one of the earliest American intellectuals to adopt the theory of evolution. In fact, Marsh and Huxley were quite close and in writing an obituary of Huxley, Marsh described him as “a guide, philosopher, and friend.” Another supporter was Franz Nopcsa von Felső-Szilvás, an Albanian Baron and palaeontologist.

This is part one of a three part series on the history of research into the link between birds and theropod dinosaurs. Look for parts two and three, to be posted tomorrow and the day after.

Sources:

Wikipedia: Franz Nopcsa - http://en.wikipedia.org/wiki/Franz_Nopcsa_von_Fels%C5%91-Szilv%C3%A1s
Wikipedia: Origin of Birds -
http://en.wikipedia.org/wiki/Origin_of_birds
Huxley’s Bibliography -
http://aleph0.clarku.edu/huxley/bib1.html
Dinosaurs and Birds -
http://www.abc.net.au/science/slab/dinobird/story.htm
Dino-Birds - The Evolution of Birds from Dinosaurs -
http://www.surfbirds.com/mb/Features/dinosaurs/dino-birds-arch.html
Wikipedia: Thomas Huxley -
http://www.surfbirds.com/mb/Features/dinosaurs/dino-birds-arch.html
Wikipedia: Othniel Marsh -
http://en.wikipedia.org/wiki/Othniel_Marsh

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