Genomic data reveal a loss of diversity in two species of tucotucos (genus Ctenomys) following a volcanic eruption

HSU, JEREMY L.; CRAWFORD, JEREMY C.; TAMMONE, MAURO N.; RAMAKRISHNAN, UMA; LACEY, EILEEN A.; HADLY, ELIZABETH A.

Scientific Reports

Nature Publishing Group

Lugar: Londres; Año: 2017

2045-2322

Marked reductions in population size can trigger corresponding declines in genetic variation.Understanding the precise genetic consequences of such reductions, however, is often challenging dueto the absence of robust pre- and post-reduction datasets. Here, we use heterochronous genomic datafrom samples obtained before and immediately after the 2011 eruption of the Puyehue-Cordón Caullevolcanic complex in Patagonia to explore the genetic impacts of this event on two parapatric speciesof rodents, the colonial tuco-tuco (Ctenomys sociabilis) and Patagonian tuco-tuco (C. haigi). Previousanalyses using microsatellites revealed no post-eruption changes in genetic variation in C. haigi, butan unexpected increase in variation in C. sociabilis. To explore this outcome further, we used targetedgene capture to sequence over 2,000 putatively neutral regions for both species. Our data revealedthat, contrary to the microsatellite analyses, the eruption was associated with a small but significantdecrease in genetic variation in both species. We suggest that genome-level analyses provide greaterpower than traditional molecular markers to detect the genetic consequences of population sizechanges, particularly changes that are recent, short-term, or modest in size. Consequently, genomicanalyses promise to generate important new insights into the effects of specific environmental eventson demography and genetic variation.