Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)


Mathematical Sciences

Committee Chair/Advisor

Dr. Sharon Bewick, Dr. Matthew Macauley

Committee Member

Dr. Keisha Cook

Committee Member

Dr. Peter Kiessler


Functional redundancy is the number of taxa that perform a given function within a given community. In most systems, high levels of functional redundancy are important, because they contribute to ecosystem stability. However, we currently have very little understanding of why functional redundancy varies among communities. One possible factor that could affect functional redundancy is environmental complexity. Many studies show that simplified ecosystems harbor communities with lower taxon diversity. What is less clear is if this simplicity and lower taxon diversity also affects functional redundancy. To answer this question, we use metacommunity models to explore the connection between environmental complexity and functional redundancy, focusing on resource diversity as our measure of environmental complexity. Specifically, we consider two paradigms for local community assembly within a larger metacommunity: environmental filtering and niche partitioning. We then use these paradigms to develop null expectations for how functional redundancy should scale with the number of resources available in a local community. Our model for environmental filtering indicates that functional redundancy of local resources is constant with respect to local resource complexity, while it increases for niche partitioning. These findings suggest that different modes of community assembly yield different relationships between resource complexity and functional redundancy. We explore these findings as they pertain empirical ecosystems and management strategies for maintaining high functional redundancy—a first step towards protecting ecosystem stability and resilience.



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