Date of Award
Ph.D. in Biological Science
Brice P. Noonan
I characterize the endogenous (gut) microbiome of Squamate reptiles, with a particular focus on the suborder Serpentes, and investigate the influence of the microbiome on host evolution and community assembly using samples I collected across three continents in the New and Old World. I developed novel methods for sampling the microbiomes of reptiles and summarized the current literature on non-mammalian gut microbiomes. In addition to establishing a standardized method of collecting and characterizing reptile microbiomes I made novel contributions to the future direction of the burgeoning field of host-associated microbiome research. Through persistent and rigorous fieldwork I amassed the largest dataset of non-mammalian vertebrate microbiomes in existence. By incorporating emergent next generation sequencing technologies and combining cross-disciplinary methods from the fields of phylogenetics and community ecology, I show that the core reptile gut microbiome is comprised of members of the Proteobacteria, Firmicutes and Bacteroidetes; and that reptile gut bacterial communities are more similar to those of birds than mammals—a previously untested hypothesis. I show that the reptile gut microbiome is strongly influenced by host phylogeny and several ecological traits including parity and foraging mode. My analyses reveal that the composition of the reptile gut microbiome is influenced by who (phylogeny), where (geographic locality) a host organism is and how she lives. Broadly, this work reflects that the microbiome of reptiles is both a phylogenetic and ecological trait that is influenced by selection and that host-associated microbiomes harbor a wealth of natural history information waiting to be explored.
Colston, Timothy Colston, "The Reptile Gut Microbiome: Its Role In Host Evolution And Community Assembly" (2017). Electronic Theses and Dissertations. 387.