Doctor of Philosophy (PhD)
Patterns of community structure may be examined using phylogenetic and morphological data; these patterns can then be used to infer the processes that gave rise to these patterns. Communities made up of similar species may be structured by habitat filtering, wherein only species with traits necessary to survive in a particular location are found there. Communities made up of dissimilar species may have been structured by competition, which reduces overlap in resource use. I examined the sensitivity of phylogenetic community structure (PCS) metrics to changes in phylogeny and community delimitation method, investigated patterns of PCS and correlation to environmental variables at multiple spatial and taxonomic scales, and assessed whether morphological data gave results similar to phylogenetic data using North American desert bats as a model system. I found that PCS metrics were robust to moderate changes to phylogeny and that these metrics also trend in the same direction regardless of delimitation method. Bat communities tended to be made up of species that were significantly more closely related than expected by chance, or phylogenetically clustered, at large spatial and taxonomic scales; this tendency towards clustering decreases with decreasing scale. Phylogenetically clustered communities also tended to occur in harsher environmental conditions than more overdispersed communities, or those made up of species not closely related. From a morphological perspective, communities were made up of species that were morphologically clustered or not significantly different from random. Morphological community structure was positively correlated with PCS, indicating that these different datasets gave similar results. These results indicate that North American desert bat communities are made up of phylogenetically and morphologically similar species and that environmental variables such as temperature and seasonality may influence community structure. This suggests that habitat filtering is playing a predominant role in structuring these communities.
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Release the entire work immediately for access worldwide.
Patrick, Lorelei Elizabeth, "Phylogenetic and Morphological Community Structure of North American Desert Bats" (2014). LSU Doctoral Dissertations. 601.