Comparative analysis of host-shift speciation in the redheaded pine sawfly, Neodiprion lecontei (Hymenoptera: Diprionidae)

University Of Kentucky Research Foundation, Lexington KY

Investigators

Abstract

The proposed research aims to understand how plant-feeding insects adapt to their host plants and the extent to which this process leads to the formation of new species in nature. Whereas most pine sawflies feed only on a single type of pine, the redheaded pine sawfly (RHPS) is a major pest of multiple pine species throughout eastern North America. Using a combination of fieldwork, laboratory experiments, and DNA sequencing, the proposed project will determine whether: (1) RHPS are adapted to different pine species, (2) RHPS from different pines are genetically distinct, and (3) RHPS from different pines can produce offspring together, which will indicate whether these are distinct, unrecognized species. Comprising ~25% of all species, plant-feeding insects are among the most diverse organisms on Earth. By describing how insects adapt to host plants and determining the link between adaptation and species formation, the proposed research will help explain the origin of a sizeable fraction of biodiversity. At an applied level, determining whether RHPS is comprised of multiple unrecognized species will have direct implications for managing outbreaks of this destructive pest. Additionally, this project's integrative nature provides an ideal training environment for undergraduate and graduate students. Finally, because host plant adaptation is an intuitive process and RHPS is part of the local fauna, this research can be used to convey basic evolutionary principles to Biology students. To this end, a related teaching module (lesson plans, presentations, activities, and assignments) will be developed and assessed in high schools in eastern Kentucky.