Tuesday, April 7, 2009

Spring Break, Part 4

One of the main reasons for our road trip to California was that my friend Lee needed to visit the UC Berkeley Museum of Paleontology (UCMP) to meet with Dr. Mark Goodwin on collaborative research on Ethiopian dinosaur teeth (Hall and Goodwin, 2007).

While Lee and Ash Poust visited UCMP, I went upstairs to take a look at the UC Museum of Vertebrate Zoology, which has a pretty decent osteological collection of marine mammals.

I had a long laundry list of material to photograph; above are a group of phocoenid crania. There is an abundance of phocoenid material from the late Neogene record of California and Mexico, including the Purisima Formation.

But, opportunistic photos of other critters, such as this bottlenose dolphin (Tursiops truncatus), were definitely not turned down.

MVZ also had a beautiful skull of the terrifying Hydrurga leptonyx, the Leopard Seal. The postcanine teeth are what really amaze me.

I was also there to look at modern Pilot Whale (Globicephala macrorhynchus) crania. Fortunately, there were several, but none from the Long Finned Pilot Whale (G. melas). I'm currently studying a Pliocene skull that is a dead-ringer for Globicephala.

Here's a real gnarly one to part you with. This was an extremely pathologic Steller's Sea Lion (Eumetopias jubatus) cranium; the entire anterior portion of the skull is deformed and offset to the left. In dorsal aspect, the skull literally takes a left-hand-turn. Crania of this species are gnarly looking enough, and this specimen takes it to the next level.

The next spring break post will have photos of specimens collected over spring break, so it may have to wait a while, as I've been too busy to prepare much of the material. So the next few posts will be unrelated, and I think I'll do a mystery fossil next.

Hall, L. and M. Goodwin. 2007. A preliminary analysis of dinosaur teeth from the Mugher Mudstone of Ethiopia. Journal of Vertebrate Paleontology 27(3):86A.


Neil said...

Nice shots! I missed that warped Sea Lion. Did you notice the large Tursiops with extremely worn teeth? Looked like he'd been eating rocks.

Robert Boessenecker said...

No, I must have missed that skull; maybe it was an extremely old individual.

That sea lion skull was by far the most pathological pinniped skull I've ever seen. The only other one that came close was this Northern Fur Seal specimen at CAS where the mandibular symphysis had inflated into a big knob of spongy bone, and the smaller teeth had fallen out, and the larger teeth (canines, premolars) went haywire in haphazard orientations, which resulted in very odd wear facets on the upper dentition.