Parasite life cycle complexity, which encompasses both host species and number of hosts in the life cycle, is one of the most fundamental and intriguing components of parasite ecology and evolution. However, because there remains a significant amount of undescribed parasite biodiversity, little is known about the evolutionary patterns or consequences of changes in life cycle complexity. This study aims to use morphological and molecular data to discover new species in the trematode (fluke) genus Alloglossidium. What makes this genus fascinating is that among known species there is variation in the number of hosts needed to complete the life cycle (2 or 3) and variation in the use of final host species (crayfishes, catfishes, leeches). Thus, this project will also use the genus Alloglossidium as an exemplary model to test evolutionary hypotheses about the origins of different life cycles and test for relationships between life cycle changes and morphological changes.
This project is scientifically important because it will contribute to a better understanding of the evolution of life cycle complexity in parasites of animals. Such knowledge is necessary to provide key insights into infectious disease transmission and the potential for parasites to infect new host species. Broader impacts include research and educational opportunities for graduate and undergraduate students in important areas such as parasitology, taxonomy, and molecular phylogenetics. Undergraduates will be recruited from the Texas A&M Regents Scholars (low income, first generation students) program and Louis Stokes Alliance for Minority Participation. To facilitate outreach to a broader audience such as K-12 educators, a web-based field guide will provide free educational resources and natural history facts on the parasites and host organisms in this study.
