The combined effects of forest fragmentation and elevation on species richness, behavior, and ecology of social Hymenoptera in Costa Rica

Forest fragmentation and elevation affect the ecology and distribution of organisms. Temperature and vegetation both change as elevation either increases or decreases. Similarly, forest fragmentation does not occur equally among elevations due to differing anthropogenic pressures at different elevations. This differential fragmentation creates highly unnaturally heterogeneous habitats that may alter patterns of species richness and community ecology. In tropical areas, in particular those areas that encompass a dynamic elevational range, directional climate change is a threat to organisms that exist among several elevations. Social insects are used as test subjects for this dissertation. Social insects in tropical areas have a high species richness that is well catalogued. They are also highly ecologically successful and fairly easy to locate. Social insects are physiologically sensitive to climate change by being prone to desiccation and therefore may not be able to migrate within and among elevations. Contained within this dissertation are three separate chapters. Chapter 1 is titled: Elevation and forest clearing effects on foraging differ between surface and subterranean army ants (Formicidae: Ecitoninae. Chapter 2 is titled: Fragmentation and elevation effects on bird-army ant interactions in neotropical montane forest of Costa Rica. Chapter 3 is titled: Elevational patterns of diversity and abundance of eusocial paper wasps (Vespidae) in Costa Rica. Contained within the chapters is evidence of elevational patterns that are affected by forest fragmentation.