CAREER: Integrating Neoecological and Paleoecological Approaches to Exploring the Effects of Climate Change on Arthropod Diversity and Community Structure

Changing temperature and precipitation patterns are affecting the structure and function of ecological systems worldwide. Most studies to date have focused on individual species responses to environmental change, but evidence for the direction and magnitude of whole-community responses, over long temporal windows, remain mostly unknown. This research will integrate paleoecology and modern ecology to study the long-term dynamics of arthropod communities across changes in precipitation, the major environmental driver structuring desert systems. This research will focus on plant and animal remains preserved in fossil and contemporary rodent middens (debris piles at nest sites) in the Atacama Desert in Chile. Rodent middens in arid environments preserve detailed information on soil arthropod communities and environmental conditions over the last 50,000 years. The integration of paleoecology and modern ecology will broaden our understanding of mechanisms shaping past and present biodiversity. Past and contemporary mechanisms underlying biodiversity change will then be used to predict the effects of future precipitation change on arid land soil communities. In addition, the project will provide many research and training opportunities for undergraduate and graduate students, as well as a postdoctoral fellow. US undergraduates will also have the opportunity to participate in a field-based Desert Ecology course in Chile.

This research project will use a unique and underutilized paleobiological archive to provide insights about the resistance and resilience of arthropod soil communities to changing environmental conditions. By integrating paleo and modern ecological data from rodent middens with isotope geochemistry, this project will test hypotheses focused on: (i) disentangling soil arthropod diversity patterns across temporal and spatial scales; (ii) mechanisms underlying community-level responses to changes in precipitation; and (iii) the magnitude and direction of biases in the paleoecological record. The latter is a crucial prerequisite for understanding past, present, and future community-environment relationships. The integration of data within and across temporal scales (contemporary, historical, and paleo), and using this data to predict changes in ecological communities, requires development of clear protocols and metrics. Hence, this project also aims to create a toolbox for ecological analyses in middens that mitigates some current limitations of midden data (e.g., temporal discontinuity and mixing, taphonomy). This toolbox will be applicable to a broad range of geographical questions and transferable to other midden reconstructions, such as those in the Sonoran Desert. Understanding long-term variation in biodiversity patterns and ecological communities along environmental gradients may allow responses of complex systems to changes in climate across spatial and temporal scales to be predicted.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.