Dissertation Research: Understanding the Functional Ecomorphology of Extinct Canids During the Cat-Gap

University Of Florida, Gainesville FL

Investigators

Abstract

The decline of species diversity is more apparent each decade. This decline is correlated with local and regional climate patterns. Understanding how related groups of animals will adapt in response to newly open community niches is challenging. However, we can look to the past to see how animals adapted to the loss of taxa. This project aims to describe how dogs in general (including foxes, dogs, wolves, etc.) responded in their anatomy and behavior during a 5-million-year time span (21 to 16 million years ago) when there were no cats in North America. This time period is known as the Cat-Gap. Working with 3D scanning techniques, including scans at a tiny scale, and using various 3D software, the researchers will analyze the anatomy of the forelimb of fossil dogs before, during, and after the Cat-Gap. Comparisons will be made with modern dogs and cats of known behavior to make interpretations of the potential behavior of the extinct canids. The primary goal is to learn whether certain canids evolved cat-like adaptations during the 5 million years when North America had no cats. This project will provide undergraduate students with opportunities to learn about research through involvement in all aspects of the research. In addition, parts of the research will be developed into a three-day high school level STEM-integrated module with the help of a local ninth grade science teacher.   The researchers will use 3D imagining techniques (NextEngine 3D scanners, nanoCT imaging) to develop a database of surface images for the humerus, radius, and ulna of extant and extinct felids and canids. These 3D surface images will then be analyzed through 3D landmark morphometrics to compare their morphology to that of fossil canids before, during, and after the early Miocene Cat-Gap (21 to 16 Ma), with an understanding that an individual's morphological adaptations are correlated with its predatory behavior. Preliminary data suggest that canids during the Cat-Gap fall within felids and outside of modern canids in their forelimb morphology. Researchers will examine if this holds true before and after the Cat-Gap, with the hypothesis that the canids were more cat-like in morphology only during the Cat-Gap. The 3D data generated by this project will be uploaded for public access in MorphoSource.