Master's Theses



Degree Name

Master of Science (MS)


Avian fossil records from across the Caribbean (Greater and Lesser Antilles) demonstrate higher avian diversity prior to extinction events due to climate change at the end of the Pleistocene and human impact across the Caribbean throughout the Holocene. Amazon parrots (Amazona) are a diverse genus of New World parrots found throughout Central and South America, as well as the Caribbean. Their phylogeny and evolutionary history, specifically for Caribbean species, has been debated in terms of source areas in Central and South America and the timing of and number of colonization events to different islands that preceded diversification into island-endemic forms. Taking a geospatial approach using GIS to study dispersal and biogeography of Caribbean amazon parrots, this study uses modified bathymetric data to model sea level fluctuations during the Late Pliocene (3.6 Ma – 2.58 Ma), the Pleistocene (2.58 Ma – 12 ka), and the Last Glacial Maximum (LGM) (~12 ka) to model potential paths of dispersal to islands of the Caribbean from inferred source regions on the mainland. Network Analyst and Euclidean raster data analysis in ArcGIS Pro 3.0 are utilized to create an optimal series of network pathways and inferred flight regions of the Caribbean at each time interval, based on an estimated maximum flying distance for amazon parrots. Previous phylogenetic information (for mainland and island forms) and Amazona fossil records are utilized as supplementary information to contemporary Amazona distributions in the Caribbean in this study. Network route, Euclidean distance, and fossil distribution mapping results added geographic context to the dispersion patterns of Greater Antillean amazons and offered a hypothesis for the diversification of Lesser Antillean amazons in spite of their paraphyletic status and poorly known evolutionary history.


Dr. Richard Lisichenko

Date of Award

Spring 2023

Document Type



© The Author(s)


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