Population genetics of the common opossum, Didelphis marsupialis (Marsupialia: Didelphimorphia: Didelphidae), in southeastern Mexico

ABSTRACT

In this study, we examined whether the genetic diversity of Didelphis marsupialis is structured or their populations maintain high gene flow as expected in common species. Forty-eight Tomahawk traps were set for four consecutive nights in The Highlands and the Central Depression, State of Chiapas, Mexico. Eight microsatellites were amplified to examine genetic diversity. Genetic structure was evaluated in terms of the null allele-corrected pairwise global F_st estimates, according to the ENA and INA methods. An Analysis of Molecular Variance and a Bayesian analysis were carried out classifying the opossums by region and population. We found a moderate genetic diversity (He = 0.57–0.62) and an intermediate genetic differentiation between population (Fst = 0.11, P = 0.009). Genetic distances showed a closer relationship between individuals from populations that had a similar disturbance level. The Bayesian analysis showed a marked structure both between regions and between populations. Our results show in the common opossum moderate levels of gene flow, limited possibly by the habitat fragmentation due to anthropogenic disturbance. Further genetics studies and conservation efforts on this marsupial are recommended. Our findings are relevant for the conservation of common marsupial species in Mexico.

KEYWORDS:

• Common marsupial
• conservation
• genetic structure
• land-use changes
• microsatellites

Acknowledgments

We thank Alfonso Ortiz Moreno, Jorge Luis Cruz Burguete, Wenceslao Bonifaz, and Trinidad Alejandro Guillén Díaz for their support with field work. We also thank Maricela García Bautista for her help with laboratory analyses.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This study is part of BCS doctoral dissertation at El Colegio de la Frontera Sur (CONACyT scholarship 175336).