A1.5 Caterpillar ensembles in a montane forest


PI(s) for this project:



Abstract:

Caterpillar ensembles on shrubs in the montane forest zone - diversity, specificity, and co-evolution

Description:

Host specificity and niche overlap among tropical herbivorous insects remain poorly understood, even though both are important for a general understanding of mechanisms underlying the extreme species diversity of tropical forests. Here, caterpillar ensembles on shrubs will serve as models to test hypotheses with regard to the diversity and function of herbivore assemblages. Target plants will be shrubs (genus Piper inside forest, various Asteraceae genera in disturbed habitats) from which caterpillar ensembles will be sampled via beating branches. On the moth side, Geometridae (the most commonly encountered and very speciose family) will be the focus, but other taxa will be evaluated as well. The geometrid genus Eois will be intensively studied, since it is very speciose in the area (about 100 species known so far) and appears to have a specific relationship to Piper. Caterpillar identification will be aided by the development of DNA barcodes that can be cross-referenced to the unique taxonomic knowledge our group has built up for the Ecuadorian moth fauna. Specific hypotheses to be tested include (a) differences in host-plant specificity between forest and disturbed habitats, (b) decrease of host specificity with elevation, (c) a positive relationship between diet breadth and elevational niche width, and (d) a higher impact of parasitoids on predictable caterpillars (i.e. those with narrow host range and/or which are common).