Looking at the nervous system of extinct animals is something that has been fairly common in palaeontology. We are frequently interested in looking at the endocranium (the part of the skull where the brain sits) in order to reconstruct the brain of extinct animals, which can tell us much about how that animal behaved. It's fairly well documented that the endocranium preserves the shape of different parts of the brain, and can therefore be reconstructed with some kind of accuracy.
But what about the rest of the nervous system? The other major part of the nervous system, of course, is the spinal cord, which transmits all that information that is important to the rest of your body to and from the brain. Plus, there's a complicated network of nerves as well. While most focus in palaeontology is on the brain, is there anything we can say about the spinal cord?
|Spinal columns of an alligator and human showing the relationship between the spinal cord, nerves, plexus location, and vertebrae. From Giffin 1995a.|
|From Giffin 1995b|
|Bird standardised spinal cord area. Columba and Turdus are both flying birds, while Struthio is an ostrich (Giffin 1995b)|
|Lizard standardised spinal cord area (Giffin 1995b)|
Unfortunately, trying to do this in fossils is more difficult. As fossils are so often found incomplete, fragmentary, and poorly preserved, this can be hard to study. Buchholtz did try to do this with some dinosaurs (Allosaurus and Saurornitholestes), but as you can see from the graph below, it's a lot noisier and not as clear as the modern animals. She also tried it with some fossil crocodilians, which seemed to work a bit better, indicating that Leidyosuchus may have used the back legs substantially.
|Dinosaur standardised neural canal area. From Giffin 1995b|
|Crocodilian standardised neural canal area. From Giffin 1995b|
I'm very interested in people's thoughts on these methods and approaches. It hasn't been used or worked on since the 1990's, and I don't know if that's because it fell out of favour for particular reasons, was not received well in the scientific community, or just that no one bothered to look at it more. I've seen it referred to in books, and never negatively, but I find it odd that no one has tried to use it again.
Giffin, E.B. 1995a. Functional interpretation of spinal anatomy in living and fossil amniotes. In: Thomason, J. (ed.) Functional morphology in vertebrate paleontology. Cambridge University Press. pp. 235-248.
Giffin, E.B. 1995b. Postcranial paleoneurology of the Diapsida. Journal of Zoology 235: 389-410.