Abbey Paulson: Community Phylogenetics
I am a Ph.D student in the EBIO department here at 欧美口爆视频 and I am researching the community phylogenetics and trophic interactions in invaded and native aquatic communities in a Mojave Desert spring system.
My research focuses primarily on the following three areas:
- Phylogenetics of invaded freshwater communities
- Landscape genetics for invasive species management
- Metapopulation connectivity in antropogenically fragmented landscapes
Phylogenetics of invaded freshwater communities
Invasive species are a major driver of biodiversity loss, pruning the phylogenetic tree of native communities through predation, competition, and habitat destruction. Understanding patterns of community reassemblage caused by biological invaders may allow for more effective restoration and management practices in invaded ecosystems. I am researching the community phylogenetics and trophic interactions in invaded and native aquatic communities in a Mojave Desert spring system (Ash Meadows, Nevada). High-throughput sequencing of aquatic environmental samples and gut contents of invasive species, using DNA barcoding genes, allows for inference of community phylogenies as well as the targets of predation by invasive species.
Landscape genetics for invasive species management
Landscape genetics is a tool that uses the genetic signature of individuals and populations across a landscape, in conjunction with landscape connectivity metrics, to infer ecological processes such as colonization and dispersal. We used this method to study invasive red swamp crayfish (Procambarus clarkii) in Ash Meadows National Wildlife Refuge, Nevada. Restoration projects in Ash Meadows seek to eradicate aquatic invaders from springs that harbor endangered populations of endemic fish, such as the Warm Springs pupfish (Cyprinodon nevadensis pectoralis), and other sensitive species. Our research used microsatellite data and mitochondrial DNA to reveal the history of the crayfish invasion in Ash Meadows - most importantly, the frequency of dispersal and location of movement routes used by crayfish during rare flooding events. This information will direct the placement of barriers in Ash Meadows to prevent re-invasion of distal springs after they have been restored.
Metapopulation connectivity in antropogenically fragmented landscapes
Rapid rates of landscape fragmentation and associated habitat loss pose a serious threat to biodiversity and the persistence of environmentally sensitive species. Understanding the impacts of land-use conversion and increased habitat isolation on ecological processes such as dispersal and gene flow may inform conservation planning and land-use management practices at the interface of urban and rural landscapes. I am studying the functional connectivity of butterfly metapopulations on 欧美口爆视频鈥檚 Front Range, which is a patchwork landscape of agriculture, open space, housing developments, and urban centers. Fine-scale genetic data generated from restriction associated DNA (RAD) tags, and GIS modeling of landscape connectivity in Circuitscape highlight corridors for butterfly movement that allow gene flow between habitat patches - an essential component in the persistence of isolated populations. This research contributes to our understanding of variable landscape permeability, and can be used locally to designate areas of habitat conservation concern.