Mussel Dimensions of Biodiversity
This project is examining the extent to which diversity at different levels of biological organization in host and microbiome communities influence functional diversity within ecosystems.This research integrates analyses of (1) intraspecific genetic diversity in a suite of freshwater mussel species, (2) phylogenetic diversity of communities of mussel species as well as their associated microbiomes, and (3) functional diversity of the mussel-microbiome holobiont. Integrating these three dimensions of biodiversity will allow us to comprehend the mechanisms that underpin the role of freshwater mussels in stream ecosystems, and to understand the fundamental ecological and evolutionary processes that structure biodiversity in space and over time.
Overlapping animal hotspots: When and where do fish and mussels overlap?
In stream ecosystems, the strongest bottom-up effects by animals have been attributed to two disparate groups, freshwater mussels and fish. How these animals overlap spatially and interact to influence nutrient cycling and resource heterogeneity is unknown. We are pursuing projects investigating the interactions among mussel and fish assemblages to understand their effects on resource distribution and fluxes across biotic and abiotic gradients. These projects are located in southern Oklahoma and are part of a collaborative effort with researchers from the University of Oklahoma.
Nowhere to swim!
Drought effects on stream fishes and
animal-mediated nutrient cycling
Global climate change is leading to more frequent and extensive stream drying events. A severe drought across the Great Plains provided an opportunity to test how a prairie stream assemblage (Kings Creek, Konza Prairie, KS) might respond to stream drying. Perennial reaches of the stream that are typically maintained by groundwater inputs ceased to flow, trapping aquatic animals in small pools with deteriorating conditions. We tracked changes in pool assemblage composition and biomass and linked these changes to losses of ecosystem function by comparing nutrients excreted by animals to nutrient uptake.
Ecological and morphological variation of darters among stream assemblages
Environmental variation can shape phenotypic variation in organisms, but most evidence for trait differentiation comes from analyses of dichotomous habitat types that differ in only one or a few key environmental factors. In reality, environmental variation is often more subtle, gradual and multifarious. Here, we investigated geographic variation in body shape of two darter species (Etheostoma spectabile and Etheostoma flabellare;Percidae) occurring along ecological gradients. We found body shape variation in both species that was correlated with variation in substrate composition. Combined analysis of both species indicated a small effect of convergence on body shape wherever they occurred sympatrically; however, shared variation was not related to any environmental variables included in the analysis.