DISSERTATION RESEARCH: Genetic Mechanisms of Spatial Eco-Evolutionary Dynamics in Range Expansions

University Of Colorado At Boulder, Boulder CO

Investigators

Abstract

The proposed research will analyze genomic patterns to test evolutionary contributions to experimental range expansion using a model laboratory system. Recent decades have seen large scale changes of species' geographic ranges, as introductions of invasive species and shifting climate patterns displace organisms from ancestral areas and expand into new regions. Many previous models of range movement rely only on ecological processes while ignoring evolution; recent research, however, suggests that evolution at the expanding range edge might play a key role. Range shifts have important conservation and economic implications that will be informed by these studies. The researchers also conduct a workshop course for K-12 teachers and provide curriculum materials to examine range shifts as a teaching tool. Several hypotheses will be tested by quantifying patterns in allele frequencies through space and time using flour beetles stored from an already completed laboratory range expansion experiment. The hypotheses to be tested are that (1) core and edge locations of a species range should grow increasingly genetically distinct through time, (2) they should accumulate different genetic variants, with edges containing variants associated with high colonization ability, and (3) the speed of range expansion should correlate with these evolved genetic patterns. Whole genome sequencing will be used to quantify allele frequencies among beetles sampled at different times and locations during the range expansion. The results will not only provide insights into the role of spatial structure in evolution, but they will also have significance for management of invasive species and species shifting ranges due to climate change.