10 November 2010

Fossil Vertebrate of the Month: Diplodocus carnegii

Last month's Society of Vertebrate Paleontology meeting was held in Pittsburgh and while animal chosen for the conference logo was the awkwardly-named tetrapod Fedexia, there is another animal that will forever be associated with vertebrate paleontology in that city's Carnegie Museum of Natural History. The museum has existed since 1895, but it was in 1898 that its namesake would spur the discovery of its most famous specimen. It's unclear whether Andrew Carnegie was alerted to the publicity value of sauropod skeletons by a visit to the American Museum of Natural History or by a sensational newspaper headline trumpeting the discovery of "The Most Colossal Animal Ever On Earth." Regardless of the cause, he hired away some of the AMNH's paleontologists and sent them to the badlands of Wyoming to find a giant dinosaur for his museum. His team succeeded spectacularly, and in 1901 the fruits of their labor were described as Diplodocus carnegii. The skeleton, which for decades was the longest - though far from largest - dinosaur known, was a huge hit in Pittsburgh and around the world, as Carnegie presented casts of the skeleton (known affectionately as Dippy) as gifts to museums in capitals across the globe. Dippy even has a couple of connections to paleontology in Oregon: D. carnegii was one of the taxa modeled by UO computer scientist/paleontologist Kent Stevens, and the cast presented by Carnegie to London's Natural History Museum was the first fossil I ever saw and was largely responsible for setting me down the path I'm still traveling today.

18 September 2010

Research Report: Mexico City

Whenever I tell anyone that I'm a paleontology student, one of the questions I inevitably get is 'Where do you do your field work?' When I tell them that I don't really do field work and that I do my research in the basements of museums, they usually say something to the effect of 'Oh, that's too bad.' Actually, it isn't. For one thing, the best science in our field is done indoors in collections, libraries, and labs. For another, I actually enjoy collections work (you can see a lot more fossils in a day in a museum than you ever will in the field). For yet another, it can take you to some of the best parts of the world. So far my collections visits have brought me home to Seattle, across the Cascades to John Day, to the great cities of California, to the university towns of the Rockies and Great Plains, to New York's unsurpassed temple to natural history, and now they've brought me to one of the greatest, most historic, and culturally rich cities on the planet. I'm writing this post from Coyoacan, a colonial town turned urban neighborhood in Mexico City. I've come to visit the collections of the Universidad Nacional Autónoma de México in order to expand the scope of my dissertation to all of North America rather than just the US. While I've made an avowed effort to cut down on travelogue-type entries on this blog, this is the first international research trip I've taken, and as such a few posts from south of the border might be of more general interest than the usual "this is what I did today and this is what I think of it" travel update. I'll do my best to supply a few of these posts on the state of my research and of paleontology and science in Mexico during the duration of my visit this week, so stay tuned.

06 September 2010

Fossil Vertebrate of the Month: Epicyon haydeni

Last month, while measuring teeth in the collections of the University of Montana and Idaho State University, I came across jaws of one of the more impressive carnivores ever to have lived. The picture at left (from UM) may not do the size of the animal justice, but Epicyon haydeni is the most massive known canid; the largest known individuals may have exceeded 200 pounds, putting them well within the size range of modern black bears. Epicyon was a member of a group of canids known as borophagines that were among the most common carnivores of the North American Oligo-Miocene. Borophagines are often described as hyena-like, and many of the larger taxa - including Epicyon - were likely bone-crushing predators. However, the group was very diverse and many of its members, especially in the Oligocene and Early-Mid Miocene, were actually fairly small; at least one species had an almost raccoon-like morphology. In many Late Miocene faunas, two species of Epicyon co-occur: the larger E. haydeni and the smaller (but still very big) E. saevus. Canid experts extraordinaire Xiaoming Wang and Richard Tedford have suggested that this is the result of character displacement, making Epicyon an excellent example of how the fossil record can record ecological and evolutionary patterns.

31 July 2010

Fossil Vertebrate of the Month: Oncorchynchus rastrosus

Salmon are a symbol of the Northwest, and with good reason: not only have they been a staple food for humans for millennia and a hugely important link in regional food chains for much longer, but they have very deep roots here. Go back to the Late Miocene and you would still see salmon in the rivers of Oregon; you would, in fact, see one of the most impressive prehistoric fish ever discovered: Oncorhynchus rastrosus, the sabertooth salmon. The features that gave the fish its common name (and its original genus name, Smilodonichthys) are its enlarged canines which, arresting as they are, are not as unusual as they might seem, as many modern salmon grow large breeding teeth while migrating upstream to spawn. The size of O. rastrosus, though, is unique: at lengths of up to 2 meters, it was a good deal larger than the largest known Chinook salmon and head and shoulders beyond sockeyes, its nearest living relatives. The sabertooth salmon was in the news this last month (both in the paper and on TV) after a team led by the University of Oregon's own Edward Davis performed a CAT-scan on its skull. The result of this research is a series of impressive 3-D reconstructions, which can be viewed in an online exhibit by the U of O Museum of Natural & Cultural History; if you'd rather see the original in person, it will be part of the museum's revamped PaleoLab exhibit opening this month.

Field Report: Field Camp 2010

As many of you may know, I was the TA for the paleontology portion of the U of O's field camp this year. Since I got back earlier this week, several people have asked me what we did and what we found. I may not be a great blogger, but even I know the first rule of journalism, so in the interest of giving the people what they want, here's a brief summary of what went on (You'll notice that I'm not giving names or locations of any of the work we did; we were at two sites, both of which are publicly owned, and since illegal collection on federal land is a recurring problem in eastern Oregon, I don't want to provide any information that an unscrupulous fossil poacher might be able to use; for those of you who are wondering, yes, we did have the appropriate permits).
The first site we visited (let's call it Site 1, since imagination is precious and should be conserved) was an exposure of the famous John Day Formation, which has yielded one of the largest and best-preserved Oligocene faunas in the world. Since the primary purpose of our trip was to teach basic paleontological field methods, the bulk of our time was devoted to creating stratigraphic sections for the outcrop. There was, however, time for fossil prospecting as well, and it was very - almost ludicrously - productive. Among the things we uncovered were rodents (particularly squirrels and aplodontids), hypertragulids (mouse deer), canids, nimravids (sabertoothed, cat-like carnivores), horses, entelodonts (bearlike relatives of pigs), and rhinos. Perhaps the most impressive specimens we unearthed were four skulls of oreodonts, pig- and/or sheep-like ungulates that were abundant in the late Oligocene of Oregon (we found ample oreodont postcrania as well, some of which are pictured above).
Our second site (being creative once again, let's call it Site 2) was less fossiliferous but scientifically much more interesting. Instead of just getting a handle on the local stratigraphy as we'd done at Site 1, we were also interested in pinning down the age and paleoenvironment of Site 2, both of which were big question marks going in to field camp. Fortunately, the fossils we found were exactly the ones we'd hoped for to be able to assign an age to the fauna: jaws of the canids Tephrocyon and Cynarctoides, teeth of the horses Archaeohippus and Merychippus, the beaver Monosaulax, and a smattering of camels and paleomerycids (antelope-like ungulates). For those of you who know your North American biostratigraphy, that places you unequivocally in the mid-Miocene (~16 Ma), which in this part of Oregon means you're in the Mascall Formation. Pinning down the paleoenvironment was made easy by the discovery of a bird (probably some kind of waterfowl) and by several shell fragments of pond turtles (I won't insult your intelligence by telling you exactly what the students concluded about the site's paleoecology, but if you can't figure out what environment is likely to be represented by waterfowl and pond turtles, I question whether this is the blog for you).
So there you have it: for a trip whose primary motivation was teaching, we had a remarkably successful couple of weeks in the field (and not just in terms of finding fossils; we were very lucky weather-wise as well, though the last couple of days did manage to break the 100° mark). We and our specimens are now all safely back in Eugene, with the latter awaiting curation and, eventually, a trip back east, where they will be reposited in the collections of John Day Fossil Beds National Monument.

30 June 2010

Fossil Vertebrate of the Month: Bradysaurus

In honor of this year's World Cup host, July's fossil vertebrate is South African. Bradysaurus (literally "Slow Lizard," represented here by a skeleton from Berlin's Museum für Naturkunde) was a pareiasaur, a group of large, armored herbivores that may be distantly related to turtles. Though pareiasaurs have been found in late Permian sites throughout the Old World, Bradysaurus is unique to the Karoo Basin north and east of Cape Town. While pareiasaurs were among the largest members of the South African ecosystem, the fauna was dominated by therapsids, or "mammal-like reptiles," including the now-iconic, predatory gorgonopsians and burrowing dicynodonts. The Karoo has been the focus of many research projects in recent years because it is one of the few regions with a terrestrial fossil record of the Permian Extinction, the largest mass extinction in the history of life. Pareiasaurs were among the groups that would not survive the end of the Permian; if you want to see one today, I recommend Oregon's very own Prehistoric Gardens.

30 April 2010

Fossil Vertebrate of the Month: Platanistoid Dolphin

Modern dolphins are by many measures the most successful group of cetaceans: they are diverse, intelligent, and in many cases have proven more resistant to anthropogenic change than their larger relatives. Some dolphins have even colonized freshwater environments. These 'river dolphins' are often referred to as platanistoids, a name based on the modern genus Platanista that inhabits the Ganges and Indus Rivers (other genera inhabit the Amazon, La Plata, and - until recently - Yangtze Rivers), but there has been much debate about whether or not all river dolphins are actually related, as was originally thought. If the world's living and extinct river dolphins really are the product of separate colonizations of freshwater habitats, then they represent a striking example of convergent evolution: platanistoids share many morphological characteristics, perhaps the most striking being a long, pointed rostrum (or snout; this feature makes them similar in form to many other fish-eating vertebrates, such as ichthyosaurs and swordfish). The specimen at left, an as-yet unnamed platanistoid from the mid-Miocene of Oregon, exhibits this characteristic rostrum. However, it was uncovered from the Astoria Formation, a marine unit from the Oregon Coast, making it a saltwater freshwater dolphin. This implies that at least one lineage of river dolphins evolved its unusual morphology before migrating inland. To see this specimen, drop by the U of O's Museum of Natural & Cultural History's Paleolab exhibit, where it will be on display until this summer; if you're in Seattle, some very nice skulls of the similar (but unrelated) Eurhinodelphis are on display at the Burke Museum's Cruisin' the Fossil Freeway exhibit until the end of May.

27 March 2010

Exhibit Review: San Diego Natural History Museum

I've been thinking for a while that it might be fun to try my hand at reviewing new (or at least relatively new) books, exhibits, papers, and the like from the world of paleontology, and this is my first attempt at doing so. Any thoughts on the format or the utility of this sort of post would be much appreciated.

Museum: San Diego Natural History Museum, San Diego, California
Theme: Paleontology
Grade: A+

This exhibit isn't new per se, but it is new to me and it's recent enough that I feel justified in reviewing it. Part of my impression of the San Diego museum may be colored by my time doing research in the collections, and it's worth noting that the facilities there are excellent, from the well-appointed prep lab to the well-organized cabinets of fossils to the offices with views over Balboa Park. That said, the exhibits there are among the best I've seen anywhere. The focus of Fossil Mysteries is deceptively constrained, displaying only fossils from the San Diego area. This is the sort of seemingly narrow focus that could lead to an exhibit consisting primarily of fossils on shelves: interesting, perhaps, to scientists, but with little value for anyone else. However, when put in the correct context, local fossils from sites familiar to museumgoers can be used as springboards to present broader concepts, and Fossil Mysteries does this to great effect. As the name of the exhibit suggests, this is done by presenting visitors with a series of questions. Some of these are rhetorical and answered fairly quickly (e.g. 'How can you tell different groups of carnivorous mammals apart?). Others (e.g. 'Why are there no more mammoths in Southern California?') are intentionally left unanswered, though visitors are provided with evidence they can use to draw their own conclusions. Of course, relying on museumgoers to actually read all an exhibit's signage is a bad bet, and several interactive displays are in place to appeal to younger visitors (my favorite was a series of self-powered displays on animal locomotion, all of which fed into the larger theme of adaptation). Models of some of the more impressive fossils are much in evidence (some of which are half skeletal, half fleshed-out); the full-sized Carcharodon megalodon and a prowling Panthera atrox are particularly impressive. A walk-through diorama of an Eocene jungle serves as an introduction to paleoecology. Many of the displays are augmented by vibrant murals by William Stout, which, taken as a whole, constitute one of the more impressive paleoartistic undertakings since Rudolph Zallinger's Age of Reptiles mural at Yale. One of the only drawbacks to Fossil Mysteries is the placement of these murals directly behind specimens, making them difficult to see and detracting from their full effect.
Many of my paleontological friends are likely reading this and despairing over another fossil exhibit based primarily on interactive displays. I would respond by saying that, first of all, we, as a discipline, should get past the delusion that fossils and fossils alone are enough to draw - and more importantly, to educate - a general audience, and second of all that, at least in this case, there's no cause for concern. One of the great strengths of Fossil Mysteries is its balance of interactive and specimen-based displays, and some of the specimens chosen for exhibit are impressive indeed. There's the San Diego ankylosaur (complete with encrusted oysters), bird tracks from the Oligocene Otay Formation, the Chula Vista walrus, a complete fossil gray whale, and several large mammals from Rancho La Brea, as well as several other smaller fossils too numerous to detail. It's hard to imagine Fossil Mysteries not having some appeal to anyone with even the remotest interest in paleontology or science in general, and because of that it stands head and shoulders above most recent paleo exhibits.

24 March 2010

Notes From a Golden Age

Apologies for the text color issues with this post; Blogger is either acting up today or I'm being an idiot. Either way, as an unredeemable perfectionist, I find it even more annoying than you do.
I spent last week visiting Oregon's southern neighbor, primarily the Los Angeles and San Diego areas, and while native Northwesterners are inherently distrustful of Southern California (LA is the Mordor to the Northwest's Rohan, with the Bay Area playing the role of Gondor in this cumbersome and hopelessly nerdy analogy), speaking purely as a paleontologist, I have to admit it's an exciting place to be right now. In fact, as the collections manager of one of the museums I visited opined, this really could be considered the golden age of Southern California paleontology.
Many people don't appreciate the wealth of the fossil record around LA and San Diego, but it really is remarkable. Everyone is familiar with the carnivores, birds, ground sloths, and ungulates of Rancho La Brea, of course, but it's far from the only Pleistocene site in the region (perhaps even more remarkable are the pygmy mammoths of the Channel Islands, the most unusual members of a unique fauna). Go back to the Pliocene and beyond and you find several remarkable marine mammals, including early baleen whales, walruses, desmostylians, and giant sea cows. Of particular interest to me are the land mammals of the Miocene, which are found in almost unbelievable abundance in the Barstow Basin and in the canyons of the Coast and Peninsular Ranges. San Diego County has its own (though, it must be said, somewhat less spectacular) answer to the Oligocene faunas of Oregon and South Dakota as well as one of the continent's better-preserved Eocene ecosystems. There are even some dinosaurs and Cretaceous marine reptiles, the tip of Baja California's iceberg.
And these fossils have plenty of people around to collect them. The Natural History Museum of Los Angeles County has one of the best vertebrate fossil collections in the country, and the San Diego Natural History Museum, San Bernardino County Museum, and Raymond Alf Museum (associated, unusually, with a high school) are none too shabby either (the San Diego museum has one of the nicest collections facilities I've seen, and I've visited a great many museums over the course of my dissertation research). Remarkably, all four of these museums either have opened or will soon be opening new paleontology exhibits (again, San Diego really excels here; more on this in a later post, if I get around to it). Several universities in the area are among the leaders of North American paleontology; UCLA and USC are probably the most prominent, but several smaller universities in the area have active research programs as well. The only loser in the world of Southern Californian paleontology at the moment is Santa Barbara, who's National Center for Ecological Analysis and Synthesis recently lost John Alroy to Australia and who's natural history museum, while housing some excellent Channel Islands specimens, has no active paleontology program of which I'm aware (though it's worth noting that UCSB is one of the regional departments with a paleo program).
I'm not in the habit of heaping praise on Southern California (so much so that I feel compelled to point out that the collections of Berkeley's UC Museum of Paleontology are still the best on the West Coast). That said, this is an economic climate in which science, along with everybody else, has had to make many cutbacks, some of them very regrettable, and to see paleontology not only surviving, but thriving somewhere in the country is encouraging. May we all soon be following their example.

13 February 2010

Fossil Vertebrate of the Month: Cophocetus

This month's fossil vertebrate - and those for all the months between February and May - is a whale. This cetacean theme is in honor of the UO Museum of Natural and Cultural History's current exhibit, Whales of Deep Time. It's the first part of the three-part exhibit Paleolab-Oregon's Past Revealed (tune in this summer to find out about Part 2). This is, to a certain extent, shameless self-promotion, as I played a small part in putting the show together (I wrote some of the labels; drop by to see if you can guess which ones!). It's also the first time in decades that we've been able to put so many of the UO's more spectacular fossils on display, so if you have any interest in Northwest paleontology, it's well worth a visit.
February's whale is Cophocetus oregonensis, a species that, as the name suggests, is unique to the Oregon coast: the type specimen was unearthed near the Yaquina Bay Lighthouse in Newport. Bones that may be attributable to another species of Cophocetus have been uncovered near San Mateo, California. The Newport specimen - currently on display in Paleolab - consists of an incomplete skeleton including a vestigial pelvis, a relic from its distant, land-dwelling ancestors. Cophocetus was a member of the Pelocetidae, an extinct family of whales found worldwide during the Miocene. Pelocetids were early balaenopteroids, making them not-too-distant relatives of modern rorquals, including humpback and blue whales.