Levels of genetic variability and gene flow among three populations of Metepeira ventura o n Santa Catalina Island, California, were evaluated based on variation at 10 gene loci . Mean heterozygosity (observed) per population was 10 .4% and mean polymorphism was 36 .7%, consistent with levels of variabilit y in other arthropods. Values of FST for the five polymorphic loci (mean FST = 0 .009) suggest that gene flow prevents the genetic differentiation of these populations . The average number of migrants per generation (Nm) among these populations is estimated to be 28 .6 . The lack of inter-population genetic differentiation may resul t from aerial dispersal and/or crawling along vegetation by M. ventura . Such similarity may also be due to the more widespread vegetative cover of Santa Catalina prior to overgrazing, which may have physically unite d these populations in the recent past, allowing for gene flow among them .
Ramirez, M. G. & L. B. Fandino. (1996) Genetic variability and gene flow in Metepeira ventura (Araneae, Araneidae). Journal of Arachnology 24: 1-8.