Invasive species and postglacial colonization: their effects on the genetic diversity of a Patagonian fish

Vera-Escalona I.; Habit E.; Ruzzante D.E.

Abstract

The present distribution of Patagonian species is the result of a complex history involving Quaternary refugial populations, Holocene range expansions and demographic changes occurring during the Anthropocene. Invasive salmonids were introduced in Patagonia during the last century, occupying most rivers and lakes, preying on and competing with native species, including the fish Galaxias platei. Here, we used G. platei as a case study to understand how long-term (i.e. population differentiation during the Holocene) and short-term historical processes (salmonid introductions) affect genetic diversity. Using a suite of microsatellite markers, we found that the number of alleles is negatively correlated with the presence of salmonids (short-term processes), with G. platei populations from lakes with salmonids exhibiting significantly lower genetic diversity than populations from lakes without salmonids. Simulations (100 years backwards) showed that this difference in genetic diversity can be explained by a 99% reduction in population size. Allelic richness and observed heterozygosities were also negatively correlated with the presence of salmonids, but also positively correlated with long-term processes linked to Quaternary glaciations. Our results show how different genetic parameters can help identify processes taking place at different scales and their importance in terms of conservation.

Más información

Título según WOS: Invasive species and postglacial colonization: their effects on the genetic diversity of a Patagonian fish
Título según SCOPUS: Invasive species and postglacial colonization: Their effects on the genetic diversity of a Patagonian fish
Título de la Revista: PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES
Volumen: 286
Número: 1897
Editorial: ROYAL SOC
Fecha de publicación: 2019
Idioma: English
DOI:

10.1098/rspb.2018.2567

Notas: ISI, SCOPUS