Afield in Oklahoma
June 25, 2018
Clouds over Black Mesa.
Baby spadefoot toad, with my index finger for scale.
Someone was here before us. Even though Black Mesa is best known for its Morrison exposures and giant Jurassic dinosaurs, there are Triassic rocks here, too, which have produced both body fossils and tracks, including these.
Seen but not photographed today:
- a group of pronghorn by the side of the road, with two babies;
- a deer that ran across the road right in front of our vehicle;
- a wild turkey foraging in the ditch next to the road;
- a few jackrabbits, and more cottontails than you can shake a stick at;
- loads of prairie dogs.
Now if you’ll excuse me, I have to go watch a thunderstorm.
Just posting a few images from my impending talk at SVPCA this Thursday.
I’ve written about the recurrent laryngeal nerve before, in Wedel (2012) and in this post. It’s present in all tetrapods, from frogs and salamanders on up. The frog RLN is shown in ventral view above, and in lateral view below, both from Ecker (1889:plate 1, figures 114 and 115). I’ve highlighted the RLN in red in both. Perhaps not a monument of inefficiency, but still recurrent, and therefore dumb.
And in a giraffe – RLN in blue, nerve path to hindfoot phalanges in red. Hollow circles are nerve cell bodies, solid lines are axons.
And in the elasmosaur Hydrotherosaurus, same color scheme plus the nerve path to the tail in purple, base image from Welles (1943).
That’s all for now!
References
- Ecker, A. 1889. The Anatomy of the Frog. 478pp. Clarendon Press, Oxford.
- Wedel, M. J. 2012. A monument of inefficiency: The presumed course of the recurrent laryngeal nerve in sauropod dinosaurs. Acta Palaeontologica Polonica 57 (2): 251–256.
- Welles, S. P. 1943. Elasmosaurid plesiosaurs with descriptions of new material from California and Colorado. Memoirs of the University of California Museum of Paleontology 13: 125-254.
