Tuesday, September 16, 2003

Coelurus

Those of you who know me are familiar with my longstanding research project. This is the one that I've been working on for years and have yet to actually write up a single paper on. Mostly this is because the direction of the research project keeps expanding and changing direction. Right now, one of the primary directions that I'm following is to accumulate a mass of diagrams of the skulls of theropod dinosaurs and then use those to do a morphometric analysis of the temporal fenestrae and possibly also the attachment sites for the pterygoidius muscles. I will then use this data to do phylogenetically independent analysis of the trends in dinosaur evolution to see if there are any trends worth noting. I will hopefully be able to describe the mechanism by which the birds inherited a brain tremendously larger for their body size than their dinosaurian ancestors. Much of this has to do with rapid variation in body size. The smallest theropod dinosaurs known are at least ten times larger than the largest of the first birds. To do this analysis correctly, it is necessary to survey a wide variety of size ranges. In my searches, I happened to come upon reports of a dinosaur name coelurus and several other closely related coelurosaurians which appear to have very complete skulls. The problem with this is that there are no diagrams of these skulls in the literature. One would think that a diagram of a dinosaur skull would be a sure fire way to get one's article into a scientific journal, yet nobody seems to have jumped at this opportunity. Thus, unless I go to Yale and to Thanksgiving Point, Utah with my digital camera, it seems unlikely that I'm going to get the images that I need. This dilemma is particularly irksome because the coelurosaurs are some of the most birdlike of the Jurassic dinosaurs. Since the birds had already evolved in the mid Jurassic, as much as 120 million years ago, that's 50 million years before velociraptor and deinonychus, the dinosaurs popular culture labels as the ancestors of the birds. Unfortunately the selection of Triassic dinosaurs seems feebly limited, with only a few varieties of coelophysis, eoraptor, herrerosaurus and a few others (all of which display very few bird-like characteristics) to represent true bird ancestors.

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