Wednesday, April 29, 2009

4th Annual Earth Sciences Colloquium

More on Puijila later on this week - don't worry, I know its a hot topic, and I love seals, but I'll post on that later.

Last weekend I participated in the 4th annual Earth Sciences Colloquium, a student research conference done in our department for students and organized completely by students (go us!). In any event, I helped out quite a bit with it, and (gasp) was the technical chair for the conference - I communicated with all the presenters, organized the technical program, and moderated the oral sessions. It was nearly enough work so that I almost didn't present my talk, the subject of this post; the title page is below. I've included a bunch of slides I thought looked neat. On the title page are the logos of various institutions loosely involved with this research (and planned research projects/collaborations): J. Geisler (Georgia Southern U.), Rachel Racicot (Yale U.), and Frank Perry (Santa Cruz Museum).

Shockingly enough, I talked about cetaceans. Since it was for a more general audience, I spent a while talking about how awesome the whale fossil record is:

Here's a very general cladogram of whale phylogeny.

One of the really apparent morphological transformations is the posterior migration of the nares. In reality, I could have added a dozen or more transitional fossils in here.

And of course there's the whole hindlimb thing. I love how the pelvic girdle of Dorudon and other basilosaurids just kinda 'floats' in soft tissue.

On to actual data... I won't elaborate on this much, as this is the subject of my SVP abstract that I co-authored with Jonathan Geisler (Georgia Southern U.), and Frank Perry (Santa Cruz Museum of NH). Above is a partial skull of a late Pliocene pilot whale superimposed over a modern Globicephala macrorhynchus.

This is a recently collected gem - an articulated petrotympanic of a new genus of porpoise or basal delphinoid. This is associated with a partial skull that has yet to be completely prepared.

Lastly, here is a pie chart I made for fun, of all the different periotic morphotypes represented in the Purisima Formation (N = 120). I can probably get N up to 150 if I need to. In other news, my Master's thesis proposal has received its informal stamp of approval from my committee, so kickass.

Edit: I really need to use the spellcheck feature more judiciously; I typed up this post pretty fast, so the typos were pretty obvious. I apologize for all the grammer nazis. Just typos, not a sign of my incompetence.


J. Velez-Juarbe said...

Neat slides!! So, in the periotic slide, the ones called Phocoenid 1-5, are these new taxa waiting to be described, or is it that id beyond family-level is not possible?
Anyways, it seems that phocoenids were quite abundant during Purísima time!
BTW congrats on your approved proposal!!

Robert Boessenecker said...

Hey Jorge,
Phocoenids 1-3 are all *potentially* new genera (#2 shows some similarities with Haborophocoena from Japan). Phocoenid 1 is the 'skimmer porpoise' that Rachel Racicot is studying, and presented on at SVP in 2007 (Racicot et al. 2007). 4 and 5 are known only from periotics (except for a partial skull I collected over spring break). Phocoenid diversity is incredibly high during the late Neogene in the Northern Pacific - there are several other fossil taxa not represented in the Purisima, that are elsewhere (i.e. San Diego Formation).