About

 

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Sarah visiting the Denver Museum of Nature and Science

I am a Research Affiliate in the Department of Biological Sciences at St. Cloud State University in Saint Cloud, Minnesota. I received my B.S. in Geology from Southern Utah University (Cedar City, Utah), M.S. in Geology from the University of Kansas (Lawrence, KS), and recently received my Ph.D. in Geology with an emphasis in Vertebrate Paleontology from the University of Kansas. I currently serve as an editor for the PLOS Paleontology Community, where I cover research published in PLOS ONE and other open access journals, promote paleontological research, create online events (e.g., AMAs and contests) and social events at conferences (e.g., Society of Vertebrate Paleontology annual meeting), and provide a venue for resources and other tools for members of the online paleontological community.

I have previously worked at several museums and institutions. I worked for two years as a preparation lab and collections manager at the St. George Dinosaur Discovery Site at Johnson Farm, where I prepared Triassic fossil fishes and monitored work by volunteers from the Utah Friends of Paleontology. At the The University of Kansas Natural History Museum and Biodiversity Institute, I worked as a graduate curatorial assistant maintaining the herpetology and entomology collections, as well as supervised fossil preparation work being done by volunteers in the vertebrate paleontology lab. I was also employed at The Field Museum as a contracted fossil preparator working on dinosaurs from the Jurassic of Antarctica (under the supervision of Peter Makovicky) and Permian tetrapods from Brazil (under the supervision of Kenneth Angielczyk).

My research is focused on investigating the evolutionary history of ray-finned fishes during the Early Mesozoic (~230–195 Ma), with a focus on the biodiversity of ray-finned fishes from the Upper Triassic Chinle Formation of southeastern Utah. I study the anatomy of extinct fishes, within a phylogenetic framework, to formulate hypotheses of evolutionary relationships and address evolutionary questions. Much of my research is focused on several groups of ray-finned fishes occurring in the Chinle Formation, many of which remain undescribed and poorly understood, both in their morphology and their evolutionary history and relationships to other ray-finned fishes. I named and described the morphology of a new genus of semionotid fish, Lophionotus, with two new species occurring in the Chinle Formation. Though the Semionotiformes (Actinopterygii, Holostei) have been the center of a few recent publications examining interrelationships within Holostei, the taxa occurring in North America have not been well-represented in these studies, particularly the taxa occurring in the Chinle Formation. My efforts to incorporate these taxa into a phylogenetic analysis have produced one of the most comprehensive hypotheses of evolutionary relationships of holostean fishes to date, and provides clear evidence that Lophionotus was closely related to the genus Semionotus within the family Semionotidae. I continue to examine new species of semionotid fishes from other sites within the Chinle Formation, as well as from the Triassic Dockum Group of New Mexico.

My current and ongoing research has focused on the †Redfieldiiformes (Actinopterygii, †Palaeoniscimorpha) and their evolutionary relationships, both within the order †Redfieldiiformes and to other palaeoniscimorph fishes. I am examining their morphology within a phylogenetic context, with the ultimate goal of assessing the role they play in their ecosystems, as well as their diet, behavior, and life history.

My research program also examines the evolution of specialized jaw and dentition morphology across several fish lineages, in order to better understand trophic niche evolution across ray-finned fishes in the Early Mesozoic. This research includes the discovery of the earliest evidence of a herbivorous ray-finned fish, Hemicalypterus weiri, from the Upper Triassic with a multidenticulate tooth morphology that is associated with herbivory by benthic scraping, which was published in 2015.

My work is a part of a collaborative effort with colleagues at the University of Utah and the St. George Dinosaur Discovery Site to explore and survey new localities and collect fossil material from the Upper Triassic Chinle Formation in San Juan County, Utah, with the intention of assessing the biodiversity found in these deposits. My work on the evolutionary history, relationships, and ecological niches of lower actinopterygian (ray-finned) fishes during the Early Mesozoic lends insight into a unique time in Earth’s history, a time that witnessed the evolution of diverse and fascinating biota (e.g., dinosaurs and archosaurian reptiles). This period in time saw major changes to the planet’s geography and several mass extinction events, both of which influenced episodes of faunal turnover and the opening of novel niches for both aquatic and terrestrial organisms.