Coming soon: Oregon coast road trip with Kirk Johnson and Ray Troll

Later today, my wife and I will depart on a four day road trip along the Oregon coastline. We were invited several months ago for this trip by the dynamic duo, shortly after meeting them in person back in October. Kirk and Ray are putting together a new book as a sequel to Cruisin' the Fossil Freeway. The new book project is titled "Cruisin' the Eternal Coastline: the best of the fossil west from Baja to Barrow". The new book will cover all sorts of paleontological sites along the west coast, including Alaskan dinosaurs, the La Brea tar pits, Californian marine reptiles, the John Day fossil beds, and due in part to the coastal focus of their new project – the extremely rich and diverse marine mammal assemblage from the west coast.Kirk Johnson and I checking out a slab of the Concretionary Bed of the Purisima Formation near Santa Cruz, California. Photo courtesy Ray Troll.

An articulated baleen whale vertebral column sits in a multiton block in the foreground, with Kirk and I looking for smaller fossils in the distance. Photo courtesy Ray Troll.

Here I've spotted a baleen whale skull to show Kirk - I first spotted this specimen in 2002, and it's still there. It's in a 400 lb block, so it is likely not going to go anywhere for a while unless some heavy machinery is involved. Photo courtesy Ray Troll.

One of the most notable series of fossil localities are exposures of various strata in the Newport Embayment (a geological basin), including the Alsea Formation, Yaquina Formation, Nye Mudstone, and Astoria Formation. The eccentric, extraordinarily gifted, and tragic figure Douglas R. Emlong amassed an incredible collection of marine mammal fossils from this area and elsewhere in the Pacific Northwest during the 1960's and 1970's, prior to his premature death in 1980. One of the purposes of our trip is to visit several of Emlong's famed fossil localities as a pilgrimage of sorts, and pay homage to the great collector.

Douglas R. Emlong, with the partially prepared skull of USNM 215068, a male skull of the early walrus Proneotherium repenningi. Presumably this is during preparation in the Paleobiology Department at the Smithsonian Institution, during one of his visits to the east coast museum. From "The Ore Bin".

Previously, in October, I met up with Ray and Kirk when they were in California for a week. We took a day trip down to Santa Cruz where I showed them some fossil localities, and all in all had a rather nice day – although I didn't find a damn thing (thanks to there being little erosion over the prior 20 months). As it turns out, Ray and Kirk have increasingly been picking my brain for details on fossil marine mammals from the eastern North Pacific, and I am pleased and excited to help them with their project; most popular books on paleontology deal with dinosaurs, and very few have ever really touched the subject of marine mammals (Neptune's Ark by David Rains Wallace is an exception). Needless to say, I am very excited for their project to take off.

I found out that if the first fossil locality you go to is kind of ugly and has few fossils (but used to have a lot...), Ray Troll will make you pose with the crappiest fossil you find and a bunch of garbage he finds laying about. Included is a toothbrush, a cardboard mayan calendar, a random photo album (yes, we looked through it) and some other odds and ends; I'm pointing to a rather unassuming scrap of sea cow (Dusisiren jordani) bone. True story.

SVP 2010: barnacle and sea lion taphonomy

Hey Folks, I know it's been a while (I feel like I say this a lot...), but I've been really, really busy. The semester has been really busy - I've been working on four different papers since I got back to school - but postings will be much more frequent for the remainder of fall. The entire month of September was spent writing a new manuscript, and getting revisions done for a manuscript that is most likely accepted for publication in the Journal of Vertebrate Paleontology. The last week of September and first week of October were spent coding characters for a poster I had with my good buddy Morgan Churchill and his advisor Mark Clementz (on pinniped phylogeny), my own poster, and two art projects I was involved with for two of the Romer Prize Presentations at SVP (by MOR/MSU students Denver Fowler and John Scannella, who between the two of them requested 9 or 10 drawings of ceratopsid skulls).Barnacles!!! (not that you've actually read about them yet). Isn't that cool?!

Six days before SVP started, I finally got the chance to work on my own poster, titled "Barnacle colonization of Middle Pleistocene Sea Lion (Carnivora:Pinnipedia) bones elucidate the biostratinomy of a fossil marine mammal". And no.... this is still not part of my thesis, although it is very similar to what I am doing. And actually, getting the poster done and now recapping on it have really helped me get reinvigorated about my thesis; I consider any time spent thinking about taphonomy is more or less time spent toward my thesis. Because this week I am starting to devote 100% of my research time to my thesis, more of my future posts this fall will be taphonomy related (and specifically marine vertebrate taphonomy, one of the most understudied and underpublished aspects of taphonomy).
But enough about my thesis. It's time for barnacle-on-bone action.

My poster from SVP (locality information is blocked out).

I had my poster presentation on Monday, day two of SVP, which was comforting because marine mammal talks and posters are usually the very last day of SVP, and during the afternoon at that (late afternoon/evening if you give a poster!). Anyway, a couple of years ago (June 2008) I was prospecting a marine Pleistocene locality in Oregon and found a couple of bones in concretions - no big whoop. Because of that, I didn't do anything with the bones for about two months, until I set 'em down in my parent's driveway and sprayed them down with a garden hose. As the soft outer rind of sediment began to wash away, I saw little white things I quickly identified as minuscule barnacles. Due to the library of papers on marine vertebrate taphonomy I've amassed for my thesis, I did a quick mental search, and quickly realized that these had never been reported as encrusting bone before. This made me really excited.

A beautiful sea lion femur with barnacles only encrusting one side.

A less cursory glance at the literature shows that these associations have indeed been recorded before in the literature, but never figured. Two examples have been figured, but either the photos are so god-awful or the item in question probably isn't even a barnacle. Otherwise, it's been mentioned as a sentence (or a part of one) before here and there. There are plenty of examples of modern barnacles encrusting old bones: I see that almost on a daily basis in the intertidal zone in Santa Cruz. To clarify, these are fossil barnacles.

The specimen where I first saw the barnacles.

So, into the nitty gritty. There are 1400+ barnacles distributed over three ones (the femur had ~200, and one of the two vertebrae is hogging 700+ to itself). They appear to be of two size classes: big ones (4-7mm with a few outliers) and small ones (~1-2mm). The big ones do not occur on any articular surfaces or in the neural canal, and predominantly only on the neural arch (i.e. few on the centra). The small ones occur pretty much everywhere, and in many cases are growing on the bigger ones. This indicates at least two colonization events. Dr. R. Van Syoc at California Academy of Sciences was gracious enough to identify the barnacles for me over the summer; they appear to be cf. Hesperibalanus hesperius. It is a species that is still extant, and is a prolific fouler of shells.

Closeup of the neural arch (left) and transverse process of the vertebrae (right).

Another interesting tidbit is the presence of barnacle attachment scars: here they are on the bone as oval-polygonal shaped traces, that are only excavated along the periphery. This has been reported before for rocks and invertebrate shells, but not bone.

So, what else can we infer? Because we know the ontogeny of modern Hesperibalanus hesperius, we can reasonably infer a gross estimation of minimum time averaging (i.e exposure time on the seafloor), given the barnacle size (basal plate diameter). The modern species only has a lifespan of 7 months, and seeing as none of these are full grown, they probably only represent 2-4 months. This is, however, assuming that barnacle basal plate diameter is constant: it is well documented that crowded barnacles only achieve a certain diameter until their basal plates are all touching and cramped (such as many on these specimens). So, it is possible that some of these were full grown, and so a time of ~ 2-7 months or so, ballpark.

The lack of any barnacles on some surfaces suggest that the surface was uninhabitable due to being smothered in sediment, or by the adherance of tissue. The femur lacks barnacles on the distal condyles, strongly suggesting the retention of articular cartilage there. Also, the femur only has barnacles on its posterior side, suggesting that the anterior side lay in the substrate and was never flipped. On the contrary, the vertebrae have barnacles more evenly distributed, so that it would be difficult not to smother barnacles at any position the bone was situated at. This suggests that the fossil was rolled around on the seafloor frequently enough to keep individual barnacles from smothering, very similar to the balanulith concept recently published in Palaios and Palaeontology. Anyway, there's much more to type about, but you'll have to wait for the paper, lest I retype everything on here.

On another note, I just got a paper on taphonomy (unrelated to this, but slightly related to my thesis) accepted in publication for Palaios, so you may be able to hear about that sometime early next year, perhaps.

Summer Adventures Part 6: Fieldwork with Richard Hilton - the "North Coast Project" continued

So now comes part 6 of a 435 part series, better know a... sorry, I thought of Colbert when typing this first sentence. NO, I assure you, my summer wasn't that long. Shortly after I returned home for the summer, my family and I retired to Lake Tahoe for the 4th of July weekend. From there I took a beautiful drive up through the eastern side of the northern Sierras, skirting Mt. Lassen and Mt. Shasta, took I-5 up to Grants Pass, and then down to Crescent City, and further on up the coast from there to meet Richard Hilton, a paleontologist at Sierra College in Rocklin, and the writer of the lavishly illustrated Dinosaurs and other mesozoic reptiles of California (If I recall correctly, Richard is doing some fieldwork with fellow blogger/faithful visitor Neil Kelley, who is researching Triassic marine reptiles). Richard also brought along his close friend Paul Goldsmith, a cinematographer.

The beach here is safe enough to drive a regular 4x4 on, without modified low pressure tires.

Hilton typically goes prospecting for mesozoic marine tetrapods and dinosaurs in California, and Neogene mammal bearing localities in Nevada. However, he did some fieldwork in the Purisima Formation at Point Reyes in the 1960's, and thus he has a soft spot for marine mammal remains.

Sea lion femur in calcareous nodule.

After a few hours of looking, I finally spotted a concretion that looked like a fossil. Sure enough, there was some bone poking out of the sides. After a split second I was able to identify it as a sea lion (Eumetopias) femur. I got this puppy prepared just before SVP, and it is covered in fossil barnacles.

Richard Hilton fifty feet up a cliff of predominantly unconsolidated sand (read: not sandstone). This photo was taken nearly straight down.

Here I triumphantly show off the gigantic mysticete scapula fragment.

Later in the day, I found a huge chunk of bone (as float) about 80 feet up a cliff. However, after spending an hour and a half looking, the three of us couldn't find the rest of the bone - we found two more pieces which attach well, but nothing else in the loose talus, or in the exposure. Perhaps it was the last remnant of something big that had eroded out of the cliff, and the rest of it had already continued down to the river below. It is a very small chunk of a very large scapula (best guess); it is difficult to say exactly what it is because of its incompleteness. However, there are two important aspects to this fossil: 1) Mysticete bones are extremely rare at this outcrop, and rare from Pleistocene deposits in general (at least in North America); 2) there are two very large shark tooth bite marks on this bone, which are subparallel (which means that tooth spacing can be determined) ; one of these marks is nearly 5 inches long! That'll make a good short paper some day.

Richard Hilton ascends the cliff, looking for more fragments of the mysticete scapula.

Very strange trace fossils from this unit.

Closeup of the strange trace fossils.

One prominent feature of this unit I found on my first visit here over a year ago were the presence of bizarre, spiky trace fossils. I've seen cross-sections of these in the Purisima Formation, but this is the only other unit I've seen these in (which also happens to be a marine, Neogene, blue sandstone deposited in the lower shoreface). F.A. Perry hypothesized in his UCSC senior thesis that these were larval chambers for some invertebrate, potentially calianassid shrimp, and that the little spikes were larval escape structures. Here at this Oregon locality they are preserved in 3D, so study of them from this locality may prove much easier than in the Purisima.

Richard searching tirelessly for bones.

Displaying the mysticete scapula fragment at the end of the day.

Wisps of dust from the overlying late Pleistocene terrace pour down as veils over the shelly early Pleistocene deposits.

Other stops on our trip were the Miocene St. George Formation near Crescent City, the Pleistocene Moonstone Beach Formation, and the Plio-Pleistocene Centerville Beach section of the Wildcat Group. We returned empty handed from these other localities.

Summer Adventures Part 4: Paleo-themed tourist traps

Towards the tail-end of the summer my girlfriend flew out to California, and we took a road trip through the Pacific Northwest. Of course, we saw the typical roadside attractions in Northern California such as the "Legend of Bigfoot", "Confusion Hill" (home of the "Chipalope" - Oh yes, half chipmunk, half antelope[fixed really stupid typo!]), "One log house", "Tree House", and the big grand daddy of them all, the "Trees of mystery" - home of a 70' tall Paul Bunyan statue.

In Oregon, we stopped at a weird place called "Prehistoric Gardens" - basically, a bunch of outdated extinct reptile sculptures in the forest. Well, let's just say that it was only worth our money because of how funky some of the models looked and how bad/off the wall/totally insane some of the information was.

The tyrant king himself welcomes weary drivers in from the road.

The second weirdest depiction of Triceratops I've ever seen.

Pretty standard Ankylosaurus model.

Oh, no! A killer Elasmosaurus (w/ lens flare!) in the middle of the... forest?

This one really screwed with me. OK, I've heard this (obviously) for Oviraptor, but ornithomimids?

My brave companion facing the evil Pteranodon.

Cold blooded? Cretaceaus?

I don't want to know how an Ichthyosaurus made its way into the forest.

In Newport, Oregon, we found the trashiest tourist souvenir shops I've ever seen, which says a lot because I've been to Disneyland, Pier 39, and Fisherman's Wharf. What's worse, these were built right next to the Oregon Coast Aquarium, and named "Aquarium Square Shops" - completely misleading. Anyway, this was literally the first thing we saw when we made it to Newport - a big blue pliosaur.

They didn't even try with this one. They call it "Nessie", the "Yaquina Bay Sea Monster", and "Kronosaurus" all within 4 feet. What?! First off, Nessie is the Loch Ness Monster. Second, I've never heard of a Yaquina Bay Sea Monster (wouldn't be a bay monster?), and it is obviously a sick marketing ploy just like Tahoe Tessie (rhymes with nessie, but at least they bothered to put a 'T' on the beginning). They didn't even bother coming up with an original name (seriously, it doesn't take more than half a second to think of a name other than one used by an already established fake sea monster), AND they go ahead and call it Kronosaurus at the same time.