What is my least appreciated paper? That’s an easy one:
Mallon, J. C., and Evans, D. C. 2014. Taphonomy and habitat preference of North American pachycephalosaurids (Dinosauria, Ornithischia). Lethaia 47:567–578.
This is a paper that I co-wrote with my good friend and colleague, Dave Evans. It’s been published for nearly three years now, and has garnered only two citations—both of which are from Dave and me! Despite this, the paper effectively debunks a widely held meme that North American pachycephalosaurs were mountain dwellers, à la big-horned sheep. This is an idea that gets a lot of play in both the popular media and textbooks (including some that have come out even after our paper was published).
The idea for the project came to mind shortly after I started my postdoc at the Canadian Museum of Nature in 2013. I was reading some papers by my predecessor here, Charlie Sternberg, and repeatedly came across this notion of his that North American pachycephalosaur skull domes tend to be well worn, “as if they had been rolled down a stream” (C. M. Sternberg. 1970. Comments on dinosaurian preservation in the Cretaceous of Alberta and Wyoming. National Museums of Canada Publications in Palaeontology 4:1–9). For Charlie, the implication was that these pachycephalosaurs must have lifted in upland—even intermontaine—environments, and not in the ancient coastal plain environments where their skull domes are typically found. Others have run with the idea since then.
But was Charlie right? Are these pachycephalosaur domes typically water-worn? No one had done the hard work of looking over the original fossil material to find out. Fortunately, most of the domes that Charlie collected were available for examination at the Canadian Museum of Nature. Dave and I further supplemented our dataset with domes from the Royal Ontario Museum and the Royal Tyrrell Museum of Palaeontology. In all, we had a respectable dataset of 187 domes, which is nothing to sneeze at (particularly if you’re a dinosaur palaeontologist). Without going into the nitty gritty of how we assessed dome wear (you can read the paper for that), suffice it to say that we found that domes were not typically worn. We also found that dome wear does not correlate with distance from their presumed origin in the Rocky Mountains, nor are pachycephalosaur remains relatively more abundant in intermontaine deposits, which we could expect if the critters lived there.
Dave and I took this to mean that pachycephalosaurs must’ve been living where we find their remains: in the low-lying coastal floodplains, alongside the more common hadrosaurids and ceratopsids. It’s an important first step in understanding things like dinosaur community ecology and beta diversity. It’s also a good reminder that taphonomic processes like erosion can actually inform our understanding of the habits of fossil organisms, and are not simply information-destroying by nature.
If anyone wants a copy of the paper (which is behind a paywall), please fire me off an email at jmallon AT mus-nature.ca.