PICS and NSF Grant #1624776
Gene frequency, Population genetics -- Mathematical models, Eclogical genetics, Gene flow
There are many causes for the genetic patterns that arise among populations across a landscape. Effective population size, natal site preference, geographic distance, or barriers to gene flow associated with landscape composition may work in opposition or in concert resulting in varying degrees of population differentiation. Here, we simulate 40 populations under 3 different ecological hypotheses of individual dispersal with random mating for 1500 generations, with scenarios: 1) dispersal and mating is dependent on habitat between populations, 2) dispersal and mating is dependent on individuals finding habitat similar to their natal habitat, and 3) dispersal and mating is dependent on habitat between populations but population size is dependent on surrounding habitat quality. We estimate the efficacy of generalized linear mixed-effect models (GLMMs) and gravity models to identify each of the 3 scenarios. Additionally, we tested the ability of 5 different genetic metrics (Dps, Fst, PCA, Nei’s D, and Cavalli-Sforza Dkf) to identify gene flow across ecological drivers, landscape composition, and time. We predict that more heterogeneous landscapes will influence genetic structure more quickly than more homogeneous landscapes and will be detected sooner by allele frequency approaches. Management of organisms in fragmented habitats, particularly those at risk, requires a knowledge of habitat effect and population genetic structure that can be informed by these types of simulations.
Alexander, Nathan B.; Gantz, Crysta; Remfert, Jane L.; and Murphy, Melanie A., "Performance of Genetic Distance Metrics in Gravity and General Mixed Effects Models" (2019). Environmental Science and Management Faculty Publications and Presentations. 275.