Meeting Abstract
Climate change is inducing unprecedented effects on species distributions, and even causing extirpation events. One way to assess the impacts of climate change includes understanding the evolutionary history of species climatic niches. Specifically, we would like to know whether species niches are conserved or divergent across evolutionary timescales. In turn, we can leverage this information to predict whether species will be able to track habitats or even expand into new habitats as conditions change. To date the ways in which micro- and macro-geographic patterns of niche evolution relate, if at all, remain largely unknown. Resolving these patterns would greatly enrich our ability to predict species’ responses to global climate change. Here we present research comparing micro- and macroclimate niche evolution in 18 species of plethodontid salamanders. We tested for niche lability using phylogenetic signal, which indicates whether variation among species in climatic traits is correlated with relatedness (higher signal) or evolves independently of relatedness (lower signal). The results showed that patterns of niche conservatism are impacted by the geographic scale of the analysis. Microclimatic variables exhibit stronger phylogenetic signal, indicating that relatedness and phylogenetic inertia shape niche evolution at the microgeographic scale. In contrast, patterns of macroclimatic variation exhibited no phylogenetic signal, indicating high niche lability and no impact of relatedness on variation. Importantly, we discovered that patterns of niche evolution are inverted at distinct geographic scales. As such, it is important for microclimatic measurements to be included in studies of niche evolution and the impacts of climate change.
