Genetic diversity and relative abundance of Didelphis marsupialis and Didelphis virginiana in Chiapas, Mexico

Abstract

In wide distribution species, as D. marsupialis and D. virginiana, large population sizes, high diversity andlittle genetic differentiation are predicted. In this study, the relative abundance of D. marsupialis and D. virginianaby capturing organisms in the Highlands and the Central Depression regions, in Chiapas, was estimated. Also thediversity and structure genetic from 7 microsatellite loci were estimated. The relative abundance was low (between0.008-0.06 individuals traps nights) and the highest incidence of opossums was observed in the Central Depression.The sex ratio was significantly adjusted to the relation 1:1 in both species. The greater genetic diversity was recordedin the Central Depression in D. virginiana (He= 0.58), with high levels of inbreeding. Genetic differentiation moderatewas observed between species (Frt= 0.13) and minimum among populations of each species (Fsr= 0.01). Although thevalues of genetic diversity were moderate, D. marsupialis and D. virginiana have low abundances with high levelsof inbreeding, which may have negative consequences in the future on the genetic variability of these species in thestudied populations.