RoL: FELS EAGER: Environmental drivers of intraspecific variation in animal behavior and consequences for ecosystem functions

Ohio State University, The, Columbus OH

Investigators

Abstract

Differences in traits among species are widely understood to influence key processes that occur in ecosystems, such as the cycling of nutrients and transfer of energy within food webs. However, substantial variation in traits, such as behavior, also occurs among individuals within a single species. It is an important scientific challenge to understand whether variation in traits within species is also important for ecosystem processes. Behavioral traits are often the first to respond to changes in the environment, and it is now widely appreciated that many species exhibit critical behavioral differences both within and among populations. This project will test the novel hypothesis that within-population differences in the behavior of two widely distributed freshwater crayfish affect energy transfer and nutrient cycling. In addition, the project will evaluate whether behavioral traits that vary among crayfish populations are related to environmental characteristics, to predict how environmental change may influence the ecological impacts of these species. Crayfish often play a central role in stream ecosystems, and there is substantial variation in feeding behavior among crayfish populations, which is likely to influence their ecological impacts. This project is potentially transformative in considering whether behavioral variation within species is essential for predicting ecological processes. In addition, it will enhance the ability of researchers to predict the ecological consequences of human-induced changes to species' traits. The project will also provide outreach to educators and scientific training for multiple graduate and undergraduate students. The objectives of this project are to determine whether behavioral variation within crayfish species: (1) affects stream ecosystem functions and (2) is predictably associated with differences in local and regional environmental characteristics. This project will be accomplished using two crayfish species that inhabit streams across a latitudinal gradient from Wisconsin through Alabama and Tennessee. Specifically, in streams across each species' range, researchers will quantify stream metabolism (photosynthesis and respiration) in different habitats and measure local (resource availability, predation) and regional (climate) environmental variables. Researchers will also examine within-species differences in the behavior of crayfish collected from these streams using laboratory behavioral assays. Finally, researchers will use larger, semi-natural experiments to examine the effects of crayfish populations that differ in behavior on critical ecosystem functions including leaf litter decomposition, nutrient cycling, and ecosystem metabolism. This high-risk project spans levels of biological organization by connecting organismal behavior to larger, ecosystem-scale dynamics. 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.