Learn about a new prehistoric animal every week with us. It will be a blast!
STL Science Center
23 March 2013
Crushed Skulls and Wonderful Preservation
Borrowed from Oceans of Kansas
The skeleton beside us here is housed in the Sternberg Museum. This picture is a bit old considering that the skeleton is now glass rectangle in the middle of the exhibit floor meaning that it can be seen from four sides; too bad it is not near the upper walkway, then it could be seen from above as well. Regardless, it is a very interesting skeleton. The skull is somewhat crushed. The pelvic and thoracic girdles are complete and the vertebrae, those pesky little fragile bits of the back, are surprisingly well preserved; my indeterminate vertebrae I am working with are a bit crushed and smaller. The skull, though, is well preserved despite its crushed state. In all honesty, as crushed as it is, it is not so destroyed that it is falling to pieces or any such thing. I am glad they have put it in a more viewable case these days so that most every angle of the skeleton is viewable by the public.
RMDRC lists this picture as the "exhibit Dolly"
The skull, when not crushed, looks a lot more like this. Notice the triangular shape of the skull, if the mouth was closed, and the grabbing teeth. These teeth are clearly designed for grasping prey much more than breaking apart prey or cutting the prey into portions. Jaw strength was probably enough to crush some smaller prey, but, if not, I would assume that some neck thrashing, think of a dog with a toy or a crocodile's death roll, would be employed by this animal to subdue prey. The prey could then be positioned and swallowed, probably head first to fold back fins into a naturally relaxed position, at the predators leisure. In those oceans at their own leisure was most likely as fast as possible in order to be alert for other predators and other meals. Interestingly, despite what we have shared about plesiosaur being slow and relaxed swimmers, RMDRC's information concurs with the theory I mentioned as my preference yesterday; that these short necked plesiosaurs were probably fast and agile swimmers. Chasing down fish and eating them on the run must have been an interesting thing to watch and speedy hunters learning to chase prey probably played some fairly interesting games as juveniles.
Our first fleshed out Dolichorhynchops. Again, notice the triangular head shape (I am starting to feel like a tour guide today). Also notice that the jaw does not form a sharp point to that triangle but is blunt at the end. The head is aerodynamic, but the jaws are not made for stabbing at fish; this means that, once again, the snake-like attack popularized in the late 19th century is refuted again by even more evidence and this time not from the flexibility of the neck. Could a blunt faced animal strike like a snake in the water? It could, but think of the loss of aerodynamics in a snake strike with a blunt jaw line. It would be terrible. Anyway, the most likely mode of attack was either in chasing down prey with speed and agility or the pack mentality which would funnel prey into a large school and then darting through the middle to seize prey, again, not striking at them with the neck but using the body and grasping teeth to grab prey "on the wing" so to speak. I would almost equate Dolichorhynchops to penguins in terms of how I see them hunting and swimming in the water; they just have an extra set of flippers to propel their much larger bodies.