Beta-Diversity of Caterpillars (Lepidoptera) in Tropical Rainforests: Testing Predictions of Host Specificity

University Of Minnesota-Twin Cities, Minneapolis MN

Investigators

Abstract

Differences in species composition among insect communities at different sites (i.e. species turnover, or beta-diversity) are poorly known in tropical rainforest. This is unfortunate as the patterns of beta-diversity are important for setting conservation priorities, as well as for our understanding ecological and evolutionary factors, which generate extraordinary species diversity, found in tropical ecosystems. This study investigates the beta-diversity of insect herbivores in lowland rainforests as a product of changes in vegetation and changes in insect communities feeding on particular host plants. Beta-diversity will be examined using caterpillars (Lepidoptera) feeding on selected host plants in New Guinea. Herbivores feeding on rare and wide spread plants will be compared to test the significance of host plant distribution and specificity for beta diversity. This project represents one of the most comprehensive studies of insect beta-diversity in the tropics and one of the first attempts to quantify beta-diversity of species-rich rainforest communities on a regional scale. In contrast to previous, largely descriptive studies, it separates and tests the effects of key factors, viz. host plant distribution and host specificity, in generating beta-diversity patterns of tropical herbivores. The project also promotes graduate student training and involves underrepresented Pacific Islanders in scientific research through parataxonomist training. The proposal also builds capacity for New Guinean entomology through training of local students, strengthens a local research station and develops the national insect collection. Furthermore, results can be applied to developing conservation strategies for NG and parataxonomists will have additional impacts through landowner education.