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.