More photos from Purisima Formation field work, 2

 We were stuck behind these jerks riding three abreast for about 5-6 miles.

 Tule Elk! After many years living in southwestern Montana, I was surprised to learn that elk of this subspecies (Cervus canadensis nannodes) are the largest by body mass in North America; Northern California is also home to the smallest subspecies, the Roosevelt Elk.

 Small individuals of the giant green anemone (Arthropleura xanthogrammica) on an exposure of the Purisima Formation.

 A starved California Sea Lion (Zalophus californianus) yearling on the beach.

 It was very strange to come across a tarantula on a beach, within a couple hour's drive of San Francisco.

 A bunch of harbor seals (Phoca vitulina) basking on what's left of a sandbar in an estuary.

 A beautiful panorama taken by my wife.

 The first time my wife ever saw California Quail (Callipepla californica), hanging out on the road here.

 A crow (Corvus brachyrhynchos) on the beach.

 A western gull (Larus occidentalis) that got really close to my wife (I'm sure food was not involved).

 My wife and Dick Hilton prospecting for fossil marine mammals.

An articulated pinniped skeleton! We collected two pinniped skeletons over the weekend at this locality; one was disarticulated and jumbled together and took 7 hours to collect; this one was a much smaller individual preserved in a much smaller volume of rock, and took about 30 minutes. This is currently being prepared at Sierra College by Dick Hilton.

To finish off this set of photos, here's how my wife spent the day watching the waves go by and us excavating; no bitter feelings, there wasn't enough room for three at the "quarry" any way. Even though it was early October, holy hell was it hot: in the high 80's, and that white rock and sand reflected all the heat from the sun. Unlike all those poor bastard friends of mine baking in 110 degree heat in eastern Montana as I write this, I had the benefit of being able to wade out into the surf every hour or so to cool off.

More photos from Purisima Formation field work, 1

Since I haven't been out in the field much down here in New Zealand during the austral winter, I've decided to occasionally post photos from past field excursions. Here, I'll show some pictures from some fieldwork last fall with Dick Hilton (Sierra College) and buddy Paul Goldsmith.

Paul (right) and I (left) investigating the face (or what's left of it) of a decomposing California Sea Lion on a long walk back from the canoes.


One of the first finds of the weekend: a proximal femur of a large (dusignathine?) walrus from the Purisima Formation, just found right on the beach.

A phocoenid (true porpoise) periotic found on the beach as well, but in a cobble. This was one of about four or five phocoenid earbones found at this locality.

Paul made a friend. This guy was just sitting there near the beach.

A nice shark tooth! A specimen of Carcharodon sp. - the serrations are fine and smaller than in extant Carcharodon carcharias, and this is instead a "transitional" specimen, transitional between Cosmopolitodus/Isurus hastalis and the modern great white. This transition has been documented elsewhere in the Purisima Formation, the Capistrano Formation of Orange County, The Pisco Formation of Peru, and (potentially) the Senhata Formation of Japan. The occurrence of these teeth is chronologically similar across the Pacific basin, and can help constrain the age of a deposit to ~7-5 Ma.

Cetacean bones galore. This little bonebed yielded a bunch of other good fossils. I don't normally collect partial vertebrae like these, although it is possible that the small vertebrae represent a partial odontocete skeleton; the large bone on the right is part of a baleen whale vertebra.

What are these bones? These two were diving into the cliff, and touching when I uncovered them. I excavated these as the tide was coming in and lapping at my backpack and other gear, and after this was wrapped in tin foil, I couldn't leave the cove by walking as the water was too deep, and had to cut hand holds into the cliff. These bones ended up being a left/right pair of mandibles from the small baleen whale Herpetocetus - they are tiny, well preserved, and probably represent a very young individual based on their 'splintery' bone texture.

Paul getting ready to ferry some fossils and tools out of the cove while the tide rises.

A huge chunk of rock we collected, with a walrus skull inside. This was my first (complete) pinniped skull, and damn was I happy to find it. Actually, I take that back; at first I was pissed, because it was in a concretion the size of a refrigerator. We found this specimen in an area with nearly no fossils, and I found it on the end of our second day in the field (out of three). We were in a remote area, and we wanted to collect it - but we had no sledge hammer, and the local hardware store closed at 4. Luckily, we saw signs for a garage sale, and although we didn't find a sledge hammer, we found an old fashioned 5 lb pipe wrench, even with a hammer head on it. Dick Hilton and I spent about twenty minutes carefully sinking chisels into the nodule with the pipe wrench, and popped off the end with the skull. We then lifted the fossil in a cargo net, lowered it into the canoe, and took the specimen out by boat. The skull is now undergoing preparation at Sierra College.

A beautiful sight on our last day of fieldwork at the locality.

Southern California Research Trip, Part 3: Natural History Museum of Los Angeles County (collections)

The purpose for our trip to visit the LACM collections was to examine a large collection of pinniped fossils housed there. Curator Emeritus Dr. "Larry" Barnes has been studying fossil pinnipeds since his master's thesis in the late 1960's (which he published in 1972, on Allodesmus and other desmatophocid pinnipeds), and has researched a wide variety of fossil pinnipeds including the early diverging and 'primitive' enaliarctines (a paraphyletic group of early pinnipeds), the relatively large and aberrant desmatophocids (an extinct group of phocoids known only from the North Pacific), all manners of fossil walruses, and fossil sea lions and fur seals. Larry has named quite a few fossil pinniped taxa from the northeastern Pacific region (Enaliarctos mitchelli, Pteronarctos goedertae, Pteronarctos piersoni, Pacificotaria hadromma, Desmatophoca brachycephala, Allodesmus gracilis, Proneotherium repenningi, Pelagiarctos thomasi, Gomphotaria pugnax, and Proterozetes ulysses), and there are a whole slew of holotype specimens to look at at the LACM - including a number of other important finds, including crania and jaws of the walrus Imagotaria downsi and the even earlier Neotherium mirum (but not quite as old as Proneotherium...). Our goal was to photograph all of these skulls and jaws, and take all sorts of measurements of them for our research. Between Morgan and I, we took about 5 gigabytes of photographs of these fossils. At the moment, we have two concurrent research projects which will soon be culminating in submittable manuscripts: a phylogenetic analysis of fossil and modern sea lions and fur seals (Otariidae; Morgan gave a talk on this at SVP this last fall), and another project describing some new material of the extinct "killer" walrus Pelagiarctos, originally described by Larry Barnes from the Sharktooth Hill Bonebed, and discovered by LACM head preparator and all around fun guy Howell Thomas. At bare minimum, we needed to examine, photograph, and measure the holotype "chin" and the referred teeth. Anything else we got done was a bonus - and our bonus included looking at dozens and dozens of skulls, jaws, and teeth of various other pinnipeds.

The hollywood hills can be seen very well from the prep lab, which is several floors up. You can just make out the hollywood sign below the top of the mountains.

The holotype "chin" of Pelagiarctos thomasi.

A referred lower left third or fourth premolar of Pelagiarctos, published by Barnes (1988).

My wife borrowed some of the clay we used for propping oddly shaped specimens up during photography and made a walrus and a manatee; the manatee even has
motorboat propeller scars (just for J. Velez-Juarbe!)

A referred lower jaw of Neotherium mirum from the Sharktooth Hill Bonebed, published by Barnes (1988); this is the only other early walrus from the middle Miocene bonebed.

My wife happened to find a book of 3D cat photos with 3D glasses. Don't ask.

Three different jaws of Allodesmus from the Round Mountain silt; but how many species? According to Barnes, there are three species: the topmost is the holotype of Allodesmus kelloggi, the middle is the holotype of Allodesmus kernensis, and the bottom one is Allodesmus gracilis. Others would lump all these in to Allodesmus kernensis (which would have taxonomic priority).

Three different early walruses! From left to right, they are Proneotherium repenningi from the Astoria Formation of Oregon (early Middle Miocene), Neotherium mirum from the Sharktooth Hill Bonebed of California (late Middle Miocene), and Imagotaria downsi from the Santa Margarita Sandstone (early Late Miocene) of Santa Cruz County, California.

The beautifully preserved holotype skull of Pacificotaria hadromma from the Astoria Formation of Oregon. According to Berta (1994), this may be a junior synonym of Pteronarctos.

Morgan and I conducting research amid a chaotic mess of fossil pinnipeds and other paleontological debris.

Downtown Los Angeles from the window in the prep lab. The US Bank tower can be seen in the middle. If you recall, it was blown to smithereens in Independence Day.

The rostrum and upper dentition of a referred snout of Desmatophoca oregonensis.

Morgan photographing the obscenely gigantic jaw of the bizarre double tusked behemoth of a walrus Gomphotaria pugnax. Seriously, that thing is offensively large.

The holotype skull of Allodesmus kelloggi, described by Ed Mitchell in the mid 1960's from the Sharktooth Hill Bonebed.

An undescribed late Pleistocene jaw of a California sea lion, Zalophus sp., from the Newport Bay mesa.

Last, but not least, another shot of those three walruses -
Proneotherium, Neotherium, and Imagotaria.

What's up next? One or two more posts on the southern CA trip including the Page Museum as well as the Santa Barbara Museum of Natural History, and eventually, I should probably try and cover some recent marine mammal research, I still have to cover a paper I got published on our wedding day, Kolponomos, and a bazillion other things.

Southern California Research Trip, Part 1: San Diego Museum of Natural History

After a ten day visit with my wife's family for Christmas in Billings, Montana, my wife and I flew back to California, and had two days to get ready for a research trip to southern California with our friend and colleague Morgan Churchill. Except that we both got sick with a nasty two day cold - we got back on a thursday night around midnight, and were supposed to leave on sunday morning (which also happened to be January 1st). Needless to say, neither of us really were able to get ready for the trip on account of how crappy we both felt, and miraculously, waking up on sunday morning for the trip, I finally felt okay to drive, and the trip was a go (only we still had to pack, and didn't get out of town until close to 1pm). It's an 8 hour drive from San Francisco to San Diego (without traffic), so we were looking at a pretty late arrival. That being said, we had just driven up to Montana a couple weeks prior, and 8 hours seemed miniscule compared to two 10 hour days across the American west. We got to Los Angeles around 7pm, and stopped in for a couple hours to visit our best friend, Lee Hall, and his awesome girlfriend Ashley Fragomeni, which was refreshing (and far too brief). We finally pulled into east San Diego to pick up Morgan at about 12:30am (after driving through the densest coastal fog I've ever seen - and that's coming from a San Francisco native!). We pulled up to the house of our gracious host (and my coauthor) Joe El Adli, who also hosted me during the SATLW meeting in June at SDSU.

Morgan measuring a skull of Valenictus chulavistensis, the "toothless" walrus from the Pliocene San Diego Formation.

We had several goals for our visit - Morgan and I are studying a new specimen of the middle Miocene walrus Pelagiarctos, which Larry Barnes descibed in 1988 from the "chin" end of a pair of mandibles and some teeth, and suggested some interesting hypotheses regarding its paleoecology. At San Diego in particular, Morgan needed to spend some time photographing and measuring every pinniped skull and jaw he could (and it took up nearly the entire time of our visit). When not helping Morgan with measurements, I was chatting with Tom Demere (paleontology curator at the SDNHM) and Joe El Adli (lead preparator of the paleo department at SDNHM) about the fossil mysticete Herpetocetus, as well as photographing some earbones and crania of balaenopterids that occur in both the Purisima and San Diego Formations.

A mounted skeleton of Allodesmus (kernensis? gracilis? depends on who you talk to) at the SDNHM, while the tail and claspers of a giant Carcharocles megalodon loom ominously above.

A closeup of the business end of Allodesmus.

A skull of Desmatophoca oregonensis, a smaller and earlier relative of Allodesmus from the Astoria Formation of coastal Oregon. This specimen was collected by Douglas Emlong, and described by Tom Demere and Annalisa Berta in 2002.

Two pinniped skulls in particular that we definitely needed to see are on display in a huge cabinet out in the Fossil Mysteries hall. During my 2007 visit, I had been let into the cetacean display case to examine and photograph a porpoise skull, but that case actually had an entire door and you could walk around in it; this display case with the walruses had a 150 pound sheet of glass that required four of us (Morgan, Joe, myself, and the SDNHM collections manager, Kesler Randall) to use large suction cups to lift the ~7 foot tall sheet off of the case (which required Joe and Kesler to go up on ladders on either side). It was quite the performance, all done prior to the museum opening.

Joe (left) and Kesler (right) brainstorming about removing the sheet of glass from the walrus exhibit.

Joe placing the suction cups on the glass. The two walrus skulls in
question - Dusignathus seftoni on the left, and Valenictus chulavistensis on the
right - can be seen at the bottom of the case.

We needed to see two specimens in particular - one is the nearly complete and well preserved paratype skull of Valenictus chulavistensis, and the other is a referred skull of the dusignathine "double tusked" walrus Dusignathus seftoni. I had really ought to blog about each of these taxa, as they are truly wonderful and bizarre creatures. The new skull of Dusignathus was collected about 6 or 7 years after Tom Demere described and named the species in 1994, and is in much better shape than the holotype specimen, which is substantially smaller, and is missing the palate (although this new larger male specimen is missing the top of the skull). Although I've seen this display several times before, I must admit I was very surpised with 1) how small the Valenictus paratype is in comparison to other skulls, 2) how light the paratype is (Tom stated that it was very poorly mineralized and held together primarily with consolidant), and 3) how damn huge the Dusignathus skull is in comparison to other skulls in collections.

Joe (in brown) and Kesler (left) set the walrus crania down onto foam, while Morgan (right) and I (gray) watch.

While Morgan was taking photos, I decided to get a different angle on some of the fossils while I had a ladder available. Here I am shooting the Allodesmus photos seen above.

Here's a nice shot I got from the ladder of a new species of balaenopterid mysticete from the Pliocene San Diego Formation (this taxon is being studied by SDSU student Jessica Martin). So far as I can tell, I've not yet seen this animal from the Purisima Formation.

A neat mount of a fossilized wing of an albatross, Diomedea sp. (but should probably be identified as Phoebastria sp.). Albatrosses are definitely huge birds - but the partial humerus of Pelagornis sp. I recently published, which was only 1/2 complete, was the same length as the complete humerus of this specimen.

My wife always makes friends on research trips.

By the end of the San Diego visit, we had each taken several gigabytes of photos, and dozens of measurements for our research. My wife had spent a fair amount of time next door at the San Diego Zoo, and at the Museum of Man. We spent wednesday morning at the SDNHM to wrap up everything before driving to LA, where we would spend our first afternoon of research at the Natural History Museum of Los Angeles County (NHMLAC), but known to paleontologists simply as "LACM" - which will be the subject of the next post.