zhejiangopterus
Online home of Henry Thomas, paleontologist and overall natural history geek
Research
I'm interested in a wide variety of paleontological and biological topics, and I'm particularly fascinated by how lineages of tetrapods evolve morphologies, behaviors, and ecologies in response to differing environmental pressures. Here are some quick summations of the research projects I have been a part of.
Luangwa Basin geikiids
For my Master's degree, I am focusing on geikiid dicynodonts. A collection of dicynodont specimens, which are currently held at the Field Museum of Natural History, hail from the Late Permian Upper Madumabisa Mudstone Formation, Luangwa Basin, Zambia, have been preliminarily compared to Aulacephalodon and Geikia. I will be describing and taxonomically assessing these specimens, determining the species-level diversity represented in the assemblage and whether any of the variation visible across these skulls represents sexual dimorphism or ontogenetic change. I will also be looking at broader patterns in phylogenetics and sexual dimorphism in Permian dicynodonts.
This research is done as part of the Peecook Lab at Idaho State University.
Azhdarchoid evolution and diversity
Since the beginning of my undergraduate degree, I've been looking into the evolution of pterosaurs. I'm particularly interested in the evolution of the toothless azhdarchoid pterosaurs. I built a phylogenetic dataset focused on azhdarchoid pterosaurs from scratch, which has recovered hitherto-unrecognized azhdarchoid clades and several newly-recognized ecological implications for the clade. I'm also in the process of describing a new azhdarchid taxon, and reassessing the diversity of Maastrichtian azhdarchids.
Pennsylvanian swamp forest paleoecology
During the Carboniferous period, roughly 310 million years ago, humid, swampy forests covered the global tropics. These forests harbored a great diversity of strange and unusual plants, including arborescent lycopods, sphenopsids, and cordaitales. During this time, icehouse conditions led to periodic changes in sea level, which are recorded in the rock record as cyclothems. When these plants died, their remains fell into the anoxic swamps, and over millions of years of fossilization these peat swamps were compressed and transformed into coal deposits. However, limestone nodules ("coal balls") often formed in this peat, and these preserve remains of plant tissues in exquisite detail.
The Phillips Coal Ball Collection is a massive dataset of plant occurrences recorded in these coal balls, collected by Tom L. Phillips and his grad students. I helped with the digitization of this dataset, which has allowed paleoecological analysis on an unprecedented scale. With the newly-digitized dataset, I helped run analyses of shifts in community composition of the floras in this dataset across space and time. A manuscript on this project is currently in preparation.
This research is done as part of the Looy Lab at the University of California Berkeley, and was sponsored by a Chemical Society of America PRF Grant and a UC Berkeley URAP Summer Research Award.