Today, a new paper describing new fossils of an early dolphin, Albertocetus, was published in PLOS ONE. This animal was named several years back, and the fossils presented in the work fill in many aspects of the critter’s anatomy and biology. I caught up with the lead author, Bobby Boessenecker of the College of Charleston, and asked him a few questions about the study.
How does an Albertocetus compare to today’s dolphins?
Externally, Albertocetus would be approximately similar to modern dolphins with a few notable exceptions. Albertocetus had a blowhole positioned relatively far in front of the eyes, and a melon placed quite far forward as well. Additionally, Albertocetus appears to have lacked a narrow caudal peduncle–this is the region in front of the flukes, which is very narrow in all modern whales and dolphins.
What do you think is the most exciting result from this paper?
Two takeaway points are quite interesting. The first is that the absence of a narrow caudal peduncle [editor’s note: the part of the tail just ahead of the fluke] in Albertocetus implies that this feature evolved independently within baleen whales and echolocating whales. Albertocetus is also the odontocete with the highest EQ (encephalization quotient) during the early Oligocene, highlighting a rapid increase in brain size across the Eocene-Oligocene boundary. Another critical point, albeit more abstract and less anatomical, is that this study emphasizes the importance of using larger sample sizes–most paleocetological studies unfortunately, and unhealthily, focus on ‘singleton’ specimens.
How did this project get started? Was there a single “a-ha!” moment that kicked it off, or was it more of a slow burn?
I was quite intimidated by archaic odontocetes after completing my Ph.D. on baleen whales, and this study was my first foray into studying xenorophids. As an undergrad/masters student I studied fossil crown mysticetes; during my Ph.D. I moved down the tree and studied stem mysticetes; and with this study, I’ve started up the base of the odontocete tree. Because Albertocetus meffordorum was already named, and this beautiful skeleton had numerous interesting additions to knowledge about Albertocetus (brain size, olfaction, earbone anatomy, locomotion), it was kind of a no-brainer to pick this as an introductory research project at CCNHM [Mace Brown Museum of Natural History, Charleston, South Carolina].
What didn’t you put in the paper that you wish you could have?
We jammed as much as I could into this paper, so not really! However, there are additional specimens of Albertocetus from the overlying Chandler Bridge Formation that are a bit more completely preserved, which would have doubled the length of the paper. I’ll take care of those later, or let somebody else worry about it. We decided to keep this paper “short” by focusing only on new specimens from the Ashley Formation.
Some of the most critical specimens in this study came from the Mace Brown Museum of Natural History, a place that might not be on the radar of many paleontologists or museum fans. Big museums often get all of the attention (and funding), though. How do you think that smaller institutions fit into the museum ecosystem? How does this paper illustrate the importance of small museums?
The Mace Brown Museum of Natural History (CCNHM) is small and one of a number of museums in historic Charleston – and perhaps one of the only free local museums, offering a free educational experience to all South Carolinians (and visitors from beyond). Despite our small size, CCNHM simultaneously possesses one of the largest collections of Oligocene cetaceans in the world (surpassed only by Charleston Museum a few blocks away) as well as the most active research program of any natural history museum in South Carolina. What small museums may lack in terms of international prestige they make up for in flexibility and intimate ties with the community.
Thank you for your time, Bobby! Congratulations to you and your co-authors!
Boessenecker RW, Ahmed E, Geisler JH (2017) New records of the dolphin Albertocetus meffordorum (Odontoceti: Xenorophidae) from the lower Oligocene of South Carolina: Encephalization, sensory anatomy, postcranial morphology, and ontogeny of early odontocetes. PLoS ONE 12(11): e0186476. https://doi.org/10.1371/journal.pone.0186476
Post header image depicts ribs of Albertocetus, from Boessenecker et al. 2017.