STL Science Center

STL Science Center

20 February 2013

Gastrointestinal Wonders

Tylosaurus, as a genus not any individual species, seems to have had a habit of dining and dying. Quite a few specimens, and this is in part thanks to the preservative nature of the ocean sediments as well, have been unearthed with lunch intact or in various stages of digestion. Items found in the stomach area (sadly no stomachs have been discovered preserved as yet) include fish, sharks (most mentions seem to be of digested teeth), mosasaurs (ex. Clidastes), diving birds (such as Hesperornis), and plesiosaurs. The diversity of diet gives us a glimpse into the diversity of habitats that Tylosaurs inhabited. They have been unearthed in Alabama, Kansas, and other western states. The locations in which they are found represent both near-shore deposits deep ocean areas. Assuming that Tylosaurs wanted to live in these areas and were not driven to near-shore environments in search of food, or to deep ocean environments in desperate searches for food, we can use this as evidence that Tylosaurus was indeed an apex predator that had free reign over much, if not all, of the Western Interior Seaway at the height of its development. The wealth of remains has helped in suggesting and supporting this hypothesis, but the remains were unfortunately mired in controversy when they first appeared.

Due to our ever popular topic of the Marsh/Cope feud, Tylosaurus was known by far too many names when it was originally discovered. Cope proposed the name Macrosaurus only to change his description of the material's placement within the English mosasaur genus Liodon. Then Marsh proposed the name Rhinosaurus from another specimen. Cope decided he liked Rhamposaurus because Rhinosaurus was an occupied name, as Marsh discovered. Rhamposaurus, too, was taken, and Marsh, therefore, changed the name once again to Tylosaurus. Thankfully, that has stayed the name of the genus for about 141 years now. Hopefully it will remain the name for at least another 141 years!
Smithsonian Tylosaurus, which was found with plesiosaur stomach contents (not pictured), and a Hesperornis following it.

No comments:

Post a Comment