COMPARATIVE ANALYSES OF EFFECTIVE POPULATION SIZE WITHIN AND AMONG SPECIES: RANID FROGS AS A CASE STUDY

It has recently become practicable to estimate the effective sizes (N e ) of multiple populations within species. Such efforts are valuable for estimating N e in evolutionary modeling and conservation planning. We used microsatellite loci to estimate N e of 90 populations of four ranid frog species (20-26 populations per species, mean n per population = 29). Our objectives were to determine typical values of N e for populations of each species, compare N e estimates among the species, and test for correlations between several geographic variables and N e within species. We used single-sample linkage disequilibrium (LD), approximate Bayesian computation (ABC), and sibship assignment (SA) methods to estimate contemporary N e for each population. Three of the species—Rana pretiosa. R. luteiventris, and R. cascadae—have consistently small effective population sizes (