Thursday, March 22, 2007

Rough reconstruction of jaw muscles in T. rex



So this is yet another one of my reconstructions, but this time, it's on jaw muscles, yeah!
The skull is redrawn from a photo I took of Stan the T. rex displayed at the Oxford Univesity Museum of Natural History. It's just a cast replica, but the quality is amazing. You can actually determine muscle scars on the surface!
So I've simply reconstructed four major groups of jaw adductor muscles; the Musculus adductor mandibulae externus (MAME), the M. adductor posterior (MAMP), M. pterygoideus anterior (MPTA), and M. pterygoideus posterior (MPTP). I included the M. pseudotemporalis as part of the MAME just for simplicity.
Muscle attachement areas were determined (pretty roughly) from visible muscle scarrings on the casts, cross-referenced with muscle attachments of modern birds and alligator (through dissections).
It's pretty interesting how, even though details differ, that all reptiles possess the same five major adductor groups. The homology is confirmed, so I'm happy to extend my comparisons to non-archosaurs, especially Sphenodon for its similarity in cranial geometry to theropods.

Monday, March 19, 2007

Testing: Deinonychus skull

This is a reconstruction of a Deinonychus skull I've attempted some time ago. All I did was scan in Ostrom's figures of the individual skull elements, scaled them to an arbitrary size (which I thought may be reasonable) and reassembled and coloured on Photoshop.

The main reason I did this was because I was not really happy with the reconstructions that are out there now. Most are based on Ostrom's initial reconstruction in his monograph which I think doesn't really look right. On the other hand, many museum displays will have reconstructions with a very pointy snout which frankly I don't really know how that came to be either. These reconstructions don't resemble close relatives such as Velociraptor or Dromaeosaurus at all. The best one I've seen so far is by Greg Paul.

And on top of that, I thought that these previous reconstructions (excluding Paul's) didn't really look like the actual fossils themselves figured in Ostrom's monograph. So, I was curious to see what Deinonychus would look like if I just assembled all the skull elements together. And above is the result. Of course I did not look at the original specimen personally so I take no credit to its accuracy. This is purely just for my personal curiosity. This one's just really a rough trial so if I get around to it, I'll do a better one using Illustrator or something.
Posted by Picasa