I recently began an NSF Postdoctoral Research Fellowship in Biology at the Field Museum of Natural History, investigating trabecular bone architecture in the vertebrae of mammals with reinforced lumbar spines, mentored by Drs. Ken Angielczyk, Lawrence Heaney, and Julian Kerbis Peterhans. Extra bony reinforcements have evolved in the spine of anteaters, armadillo, and several shrews, but it is unclear if these reinforcements serve similar functions because their extreme and unusual shapes make them difficult to compare.
For this project, I am using specialized imaging techniques to analyze the internal structure of the vertebrae in shrews, anteaters, and armadillos. Internal bone structure is indicative of adaptation in response to forces applied to a bone, so my analyses will determine possible functional similarities between these vertebrae that are difficult to detect using external bone structure.
NSF Postdoctoral Research Fellowship in Biology FY 2018: Abstract.
Mammalian FauNAL dynamics
I worked with collaborators (both geochronologists and paleontologists) to understand fine details of the mammalian biotic recovery following the Cretaceous-Paleogene mass extinction event in northeastern Montana.
species discrimination in the fossil record
Using geometric morphometrics and linear measurements, I worked with my advisor to elucidate the morphological differences among members of a Cretaceous-Paleogene multituberculate species complex (Mesodma), and make the best of a fossil record made mostly of isolated teeth.
Mammalian dental ecomorphology
I used µCT scans of mammalian teeth to relate dental surface morphology in earliest Paleocene mammals to dietary preference, via quantitative comparison with the teeth of modern mammals with known diet.
Inferring diel activity pattern from bony orbit dimensions
In summer 2011, I received an NSF Research Experiences for Undergraduates (REU) fellowship to work with Ken Angielczyk (Field Museum of Natural History) to study the relationship between bony orbit dimensions and diel activity pattern (DAP) in sciurid rodents, with the eventual goal of using orbit dimensions to infer activity pattern in non-mammalian synapsids. We collaborated with Lars Schmitz (Claremont-McKenna) and Steve Wang (Swarthmore) to investigate the possibility of predicting DAP in sciurids using orbit measurements and other cranial dimensions, using a variety of quantitative methods, including phylogenetic flexible discriminant analysis, classification trees, and logistic regression. We found that although there are some interfering phylogenetic factors, nocturnal and non-nocturnal sciurids can be differentiated from one another with over 80% accuracy using all the methods we investigated. Our results indicate that these analyses offer several viable options for predicting DAP in the fossil record, but such analyses should be conducted in a phylogenetic context whenever possible.
Smith, S. M., Angielczyk, K.D., Schmitz, L., Wang, S.C. In press. “Do bony orbit dimensions predict diel activity pattern in sciurid rodents?” The Anatomical Record.
Other mammalogy activities and fieldwork
Phyllostomid Bats in La Selva, Costa Rica
During two field seasons, I assisted with collection of tissue and fecal samples, ectoparasites, echolocation call data, and behavioral data on a variety of phyllostomid bats in La Selva, Costa Rica. Leith Leiser-Miller and Dr. Sharlene Santana were kind enough to allow me to assist with their work on the coevolution of the phyllostomid genus Carollia and volatile organic compounds (VOCs) in the plant genus Piper. Learn more about that project here.
Extant Mammalogy Prep work
I was a volunteer in the Burke Museum's mammalogy collections for four years. My work as a volunteer consisted of extant specimen prep, including construction of museum taxidermy skins, tissue and fecal pellet collection, skinning and cleaning small to large zoo specimens (tree shrew through gorilla), and joining the mammalogy team for specimen salvage in the field. I have also learned techniques for skeletal mounts and live mount taxidermy of small- to medium-sized taxa..