Sunday, August 7, 2011

Recent fieldwork in the Purisima Formation, Part 1: Gigantor whale jaw

If you pay attention to paleo-related news on the intertubes, you may have seen a recent article about a 700 lb dinosaur bone excavated from the Morrison Formation near Fruita, Colorado. Fellow MSU student Krista Brundridge was even interviewed and involved in the excavation. They only state that the bone is from the animal's back, so I can only assume that it's a huge sauropod vertebra. Which means that maybe the kind folks over at SV-POW! will be drooling over the news. If people really wanted to dig up humongously sized plaster jackets, they'd come to California and dig up whales. Why, back in may, Dick Hilton and I prospected a locality in the Purisima that hasn't been collected by paleontologists in over twenty years, and over the course of two days, found dozens of multi-ton blocks just sitting there on the beach. Many of them had vertebrae (which unlike those of sauropods, are much more conservative in their anatomy), ribs, and other odds and ends. However, I counted many that had skulls. One block that was the size of a pickup truck had a complete skull, at least one lower jaw, and apparently part of an articulated vertebral column and ribcage.

Me posing with half of a gigantic whale jaw.

Wait a second, you say. Dinosaur paleontologists scrounge up every scrap of bone, and re-re-describe old fossils (i.e. Dryptosaurus was first described, then re-described, and then re-re-described), and bitch and moan about there not being enough material for new researchers. How would complete skulls of baleen whales just sit on the beach without some intrepid explorer to come along and excavate or collect them? Below, I've got a photo of what used to be a complete baleen whale jaw sitting in a large boulder, ~20 feet above the beach. I climbed up to it, which was pretty hairy – usually the Purisima Formation is sandstone, and easy to carve handholds in, but this was nasty hard fractured mudrock. This jaw must be in a concretion that weighs the same as my small Honda. For baleen whales, jaws are "relatively" diagnostic (see here, here, and Boessenecker 2011), so specimens like this are of interest. Baleen whale skulls are of course diagnostic, and it is unfortunate that they are languishing like this.

It was kind of a pain to get down from there.

One problem, you might say, is that they're big, and in very tough rock. Yes, I spent five years of my life (intermittently) preparing a mysticete skull in a concretion that I collected from the Purisima Formation. Sure, it's a big heavy skull, but surely smaller and less heavy than any ceratopsid skull you can point at. Obviously, blue whales have bigger crania than dinosaurs like Triceratops. Most fossil mysticetes have skulls that are smaller than or roughly the same length as the largest "Torosaurus" skulls, but many museums out there don't hesitate to go dig up more Triceratops skulls. Is it the often concretionary matrix and the time-intensive nature of the preparation that makes whale fossils "unpopular"? I don't think so, because I can't count the number of dinosaur bones (even undiagnostic material like ribs) encased in hard rock being prepared.

Permanently borrowed from SV-POW! Thanks guys, this image is awesome.

Are whales and whale fossils just unpopular within vertebrate paleontology? Maybe. Given how whales captivate the imagination – mind you, not in the gory, Velociraptor-chasing-kids-through-a-kitchen and lawyer-eating sort of way but the holy-shit-its-a-brachiosaurus-on-a-grassy-hill sort of way – I highly doubt that cetaceans lack the cool-factor. They may not have big sharp pointy teeth... oh shit, I forgot that fossil sperm whales are far more impressive than any puny theropod. Sorry, Livyatan beats T. rex. I think the real problem is that we have the Jurassic Park generation in vertebrate paloentology now – and not to sound like a bitchy hipster, although I am of the correct age group – I was into paleontology before Jurassic Park came out.

Nevermind that in the background.

Perhaps this is a problem that is, within the United States, unique to Northern and Central California. Southern California fossil cetaceans are really well taken care of, and get excavated and pampered at places like LACM, the Cooper Center, and the San Diego Natural History Museum. The extremely rich Calvert Cliffs and other Mio-Pliocene units of the Chesapeake Group of the mid Atlantic coastal plain are covered by the Calvert Marine Museum, the Smithsonian, and my dear friend Butch Dooley at the Virginia Museum of Natural History. Florida fossils are generally covered by the FLMNH and the University of Florida. The comparatively rich fossil record in the Oligocene and Miocene of Washington State (and parts of Oregon as well) are covered by the Burke Museum in Seattle. However, all of the UCMP students who collected a ton of material from Northern California in the 1970's and early 1980's moved on elsewhere.

I don't mean to complain – having a surplus of fossils available for my research is nothing to complain about. However, it is depressing if not distressing to see so many fossils I could not collect, prepare, and study alone in five or six lifetimes, just sitting out there on the beach. So: to all of you dinosaur folks who feel perhaps the field is a little too crowded, too much of a circlejerk, or whatever, come join marine mammal paleontology! Trust me, there are is a large hoard of new genera and species out there just waiting for the taxonomically hungry. In five years of serious collecting, I've got enough material to research for another ten years, and this is barely scraping the surface. So, this is a call for action! If you're interested in marine mammal paleontology, go dig up a whale (instead of Apatosaurus #32, or NewGenusOfUninterestingChineseDinoBird #54, or re-re-redescribing something everyone is already familiar with) or find someone who can help you (...or me, for that matter).

Unfortunately, the sad reality is that that jaw I posted above will probably not be collected. I don't have the funding, resources, or the connections (read: friends with heavy machinery) to collect stuff like that now. To be honest, it isn't complete enough for it to be worth it anyway. But that's besides the point: it was at one point, and another one will come along that will be worth collecting. Will we be up to the challenge?

Sorry for the rambling here, the rest of these posts will be about fieldwork I did with Dick Hilton in May, I promise!


Doug said...

While i do still hold an interest in dinosaurs, that was well said. I think the great appeal of dinosaurs is that they are so different from anything living today, whereas mammals are so much like what we have today. To me, though, that makes them more interesting; they put a weird spin on the animals we are very familiar with (ie midget whales, giant sharks, camels in North America). But for some reason every scrap of dino bone is collected while mammal fossils sit out to rot. Like my sea cow. No one was interested in it. I bet if it was the rib cage of a hadrosaur or ceratopsian no one would have hesitated to dig it out. Back when i thought it was a whale, Kathleen Springer of the San Bernardino County Museum called it an "AFW": Another Freaking Whale. She went on to gripe about how whale post crania is often too big to dig out, prep, and store and are too common while not being diagnostic enough to be worth the effort.

I do agree that interest in dinosaurs (and mesozoic critters in general) is somewhat disproportionate. I'm sure Jurassic Park had a hand in that. Even though i'm more of a Cenozoic guy, i still want to go look for dinosaurs, albeit in less conventional localities (Two Medicine formation in Montana and Kirtland formation in New Mexico). But if i can ever get my museum off the ground mammals would be on equal footing. In fact i dream of creating a hall for marine mammals. Marine reptiles always get these spectacular displays, but i have seen few with fossil marine mammals. I mean look at the Bearpaw Sea exhibit at the Royal Tyrrell Museum: . Imagine the same thing but instead of plesiosaurs and mosaurs it has whales, walruses, and sea cows.

I hope that my museum can look for marine fossils at Avila, Sharktooth Hill, and maybe even the Purisima formation. I know my museum is nothing but a fleeting dream and may never be anything more than a bunch of spare time amateurs, and i know that the market is so thin that you have to take jobs where you can get them, and even though someone of your caliber wouldn't waste their time with a chickenshit outfit like ours, there will always be a place for you and your marine mammas at my museum.

Alton Dooley said...

I once had to leave a whale to weather away on the Potomac River. It was intriguing, because it was in the Eastover Formation, which doesn't produce a lot of whales, and it was big (balaenopterids are known from the Eastover). But it was 70 feet up a 140-foot cliff. With what it would have cost me to get that whale out, I could have excavated at Carmel Church for years. That's assuming it would have been possible at all.

It's painful to have to leave those things behind, but that's the way it goes sometimes.

I'll say, though, if you manage to drag a few of those Herpetocetus-skull-bearing concretions up the cliff, VMNH will be happy to accept them!

Mere said...

Nice post, Bobby. Couldn't agree more. I think "AFW" is a Larry Barnes term, and it's been adopted by paleo mitigation in southern California too. I cringe at the early Miocene Vaqueros stuff that wasn't collected because it was an AFW and probably not diagnostic... until it turned out some of those little mysticetes had teeth.
The problem is, we can't possibly figure out if it's important and should be collected until we know what we already have. I have 365 unopened jackets here, many with whales in them, that are needing people to do the work. And even most of the open ones haven't been described yet. We joke of having a "Save the dead whales" campaign.

Alton Dooley said...

Yep, I have that same problem...approximately 80 unopened jackets from Carmel Church alone...and I just brought back 3 more last month.

ReBecca Hunt-Foster said...

When you live 10 minuets from the Morrison Formation, and the museum you work for is based on local paleontology, you tend to dig there. I agree, Apatosaurus is well known. But if no one had ever bothered to dig at the Mygatt-Moore Quarry we would not have Mymoorapelta, a animal that was new to science. So while the Morrison Formation is boring and all "done" to some people, there are a few of us who are lucky enough to live near it and know that there is still valid and important work to be done here.

I think many students in paleontology forget there is a nice exciting world of fossils outside of the Mesozoic. Enjoy your whales. I am off to work on a Morrison egg site tomorrow :)

Anonymous said...

Hello. I often read your articles and that one is pretty damn right.

People are embarassing to all the time focusing on dinosaurs.$

But I guess the problem is that most of the ancients whales are small by today's standards so more or less "forgettable" for the average joe, and some specimens possibly lack of media coverage.

Regarding Livyatan, it's obvious it beats T. rex, but after all a number of marine reptiles and crocodiles beat T. rex as well in terms of gigantic macro-hunters !

That being said, do you think Livyatan represents the most powerful macro-hunter we know in history ? I admit I've been fascinated by its discovery but I was disappointed that we only have a range of its size and no more remains indicating possibly larger or smaller estimates...