Research Projects

I am a vertebrate paleontologist and Ph.D. candidate at the University of Florida whose research integrates museum collections, morphology, paleobiology, and evolutionary history to investigate patterns of mammalian diversity and adaptation through the Cenozoic. My work focuses on fossil mammals and the use of quantitative approaches, including geometric morphometrics, Bayesian phylogenetics, and AI to address questions in evolution, ecology, and functional morphology. In parallel, I develop and coordinate programs that connect scientists, educators, students, and communities through authentic STEM experiences — expanding access to Earth and environmental sciences across Florida.

Fossil Horse Macroevolution

Investigating macroevolutionary transitions in Neogene Equidae using phenomics and machine learning

Fossil horses (Family Equidae) provide one of the most complete records of mammalian evolution in the fossil record, spanning over 55 million years in North America. My dissertation research focuses on macroevolutionary transitions in Neogene fossil horses, leveraging phenomics — the large-scale, quantitative measurement of phenotypic variation — alongside machine learning to detect patterns of evolutionary change across time and space. By integrating museum collections from across North America with computational approaches, I aim to reveal how populations of fossil horses changed morphologically across major climatic and environmental transitions.

Geological range and North American Land Mammal Ages of latest Hemphillian equid faunas
Figure 2. Geological range and North American Land Mammal Ages (NALMAs) of latest Hemphillian, Hh4 interval equid faunas in North America, including the four widespread and two endemic species (Killingsworth and MacFadden, 2023).

A central component of this work involves applying interpretable deep learning models to images of fossil horse teeth, which preserve detailed morphological information about diet, ecology, and phylogenetic relationships. This approach allows me to quantify subtle variation across large sample sizes that would be impractical to measure manually, opening new windows into paleopopulation structure and evolutionary dynamics. This work was recognized with a Romer Prize Session presentation at the 2026 Society of Vertebrate Paleontology meeting.

I also investigate species occurrence patterns of Late Miocene horses from Florida, examining whether gaps in the fossil record reflect genuine ecological absences, sampling biases, or both — an important methodological question for interpreting evolutionary and biogeographic patterns from museum collections.

Publications

Killingsworth et. al. ( )
MacFadden et. al. ( , )

Acknowledgements

This research was supported by:

American Museum of Natural History, UC Museum of Paleontology, Smithsonian Institution, Florida Museum of Natural History