|Discovery of the "grand animal", Mosasaurus hofmani, at Maastricht. Engraving by G. R. Levillaire, from Wikimedia Commons.|
|A cladogram showing the relationship between selected diapsid groups. As you can see, mosasaurs are not dinosaurs.|
|A life restoration of Tylosaurus, by Charles R. Knight, from Wikimedia Commons.|
|An updated life restoration of Platecarpus, using the skeletal reconstruction of LACM 128319 as a reference. Created by Dmitry Bogdanov, from Wikimedia Commons.|
As if that weren't cool enough, just last Friday, another paper was published in PLos One on mosasaurs. This time, the mosasaur being discussed was Prognathadon, but no one was really concerned with its tail. The authors were interested in its proteins. That's right, I said proteins. Lindgren was at it again, this time using synchroton radiation-based infared microspectroscopy (a way to study and identify the chemicals in something) on a 70 million year old mosasaur bone (2011). The authors of the paper found that type I collagen, the most abundant protein in bone, managed to survive over the millennia, proving once again that primary soft tissues and biomolecules can be preserved, and in marine sediments at that! Amazing.
|A Mosasaurus skeleton on display at the Maastricht Natural History Museum in the Netherlands. Photo by Wilson44691, from Wikimedia Commons.|
So basically, mosasaurs were fast, terrifying, Cretaceous "sea monsters" that came in a multitude of shapes and sizes and had a global distribution. They were the dominant marine predators in an underwater world that was full of other nasty critters, be they marine reptiles, bony fish, or elasmobranchs. Whether out in the open ocean, or close to the shoreline, your chances of running into one were pretty good, but your chances of it being a pleasant encounter, were certainly not. The more fossils that we uncover, and the more research that is done on this fascinating group of animals, the more we learn about them. But of all the important things to remember about mosasaurs, this one is key: they are not dinosaurs.
(For more on mosasaurs or the other critters from the Late Cretaceous Western Interior Sea, I highly recommend the Oceans of Kansas Paleontology website, or the book Oceans of Kansas, both by Michael J. Everheart.)
Lindgren, J., jagt, J.W., & Caldwell, M.W. 2007. A fishy mosasaur: the axial skeleton of Plotosaurus (Reptilia, Squamata) reassessed. Lethaia, 40: 153-160. doi: 10.1111/j.1502-3931.2007.00009.x
Lindgren, J., Caldwell, M.W., Konishi, T., & Chiappe, L.M. 2010. Convergent Evolution in Aquatic Tetrapods: Insights from an Exceptional Fossil Mosasaur. PLoS One 5(8): e11998. doi:10.1371/journal.pone.0011998
Lindgren, J., Uvdal, P., Engdahl, A., Lee, A.H., Alwmark, C. et al. 2011. Microspectrospic Evidence of Cretaceous Bone Proteins. PLos One 6(4): e19445. doi: 10.1371/journal.pone.0119445