Sewanee Graduate Co-authors Comparative Biology Manuscript

David Spears, C’15, parlayed the results from laboratory independent study and a 2015 summer research internship in the laboratory of Sewanee professor Brandon Moore into a peer-reviewed journal publication. The manuscript, Morphological Characteristics Regulating Phallic Glans Engorgement in the American Alligator,will be featured in the upcoming October special issue of Integrative and Comparative Biology entitled The Morphological Diversity of Intromittent Organs.


Sexual selection pressures drive copulatory organs into a myriad of species-specific shapes, each putatively working to optimize male reproductive fitness.  Across many species, little is known about the functional morphology of this diversity of copulatory organs, including the American alligator.  David employed histological tissue sectioning and histochemical staining of alligator tissues to visualize structural elements that impart rigidity and elasticity characteristics. 


Understanding these extracellular matrix architectures provides insights about phallic material properties that result in tissue strength and flexibility in response to copulatory forces. Knowing how shape and function influences individual reproductive fitness not only aids basic biological understanding, but also better informs threatened species conservation breeding programs.