Population differentiation and genetic diversity of a population of Basilichthys microlepidotus inhabiting an artificial water body in the Maipo basin
Date:
Human activities, especially since the industrial revolution, have caused major alterations to the environment, producing diverse effects on natural populations. For example, changes and fragmentation of freshwater flows, which in turn produces changes in the genetic diversity of populations, observing in many cases a decrease in this, which increases the probability of extinction of the population in the short term and in the long term decreases its capacity for evolutionary adaptation. In Chile, one of the basins most intervened by humans is the Maipo River basin. Previous studies carried out in the basin determined the population structuring of the silverside endemic to Chile Basilichthys microlepidotus. Recently a new group of silversides was detected in the Laguna Esmeralda, Melipilla (33°38´50”S, 71°16´0”W), a body of water that was created artificially in 1992 as an indirect action of the construction of the Autopista del Sol. The objective of this work was to characterize the new group of silversides found in the Laguna Esmeralda, determining its genetic diversity, allelic richness and number of alleles and if they constitute or not a new population with respect to those already characterized previously. For this, 8 microsatellite markers were used, which showed that the group inhabiting the Laguna Esmeralda corresponds to an independent population and that it presents the lowest or one of the lowest values of genetic diversity, allelic richness and number of alleles compared to the other five populations of the basin. These results suggest a possible founder effect in the population of silversides inhabiting the Laguna Esmeralda.
JORGE CORTÉS-MIRANDA, DAVID VELIZ, MICHEL SALLABERRY, CAREN VEGA-RETTER
Acknowledgments: FONDECYT 11150213 Sponsorship: Professor Irma Vila