Dissertation Research: Ecological and Evolutionary Effects of Land Use Changes on Butterflies

University Of California-Santa Barbara, Santa Barbara CA

Investigators

Abstract

Habitat loss and conversion are major contributors to biodiversity loss. This dissertation research project addresses how land use conversions may contribute to morphological changes in butterflies, ultimately changing dispersal capabilities and influencing evolutionary pathways. The objectives of the project are: 1) To evaluate the effectiveness of dispersal proxies for butterflies; 2) To determine the effects of urban growth patterns and habitat fragmentation on butterfly dispersal; and 3) To evaluate whether dispersal morphology in selected California butterfly species has changed in response to landscape changes. Butterflies exhibit a range of dispersal behavior from sedentary to mobile. These behavior differences contribute to a species' success in spatially structured populations. Within a population there also exists a range of dispersal capabilities that are influenced by selective pressures from the environment. Thus, changes in the distribution of habitat can alter dispersal capability through selection, ultimately reflected in morphology. This project will use an urban growth model to analyze different landscape patterns using measures of connectivity for different disperser types. Museum specimens will be used to investigate morphological changes over time in six butterfly species. The results of this research will enhance our understanding of how land use changes and landscape patterns influence population processes that may lead to evolutionary changes or species extinctions.