Population genetic structure of long-tailed pygmy rice rats (Oligoryzomys longicaudatus) from Argentina and Chile based on the mitochondrial control region

$50.00 plus tax (Refund Policy)

Buy Article:

Abstract:

The rodent Oligoryzomys longicaudatus (Bennett, 1832) (Rodentia, Cricetidae) inhabits southern forests of Argentina and Chile, a region severely affected by glaciations during the Pleistocene-Holocene periods. We evaluate here the diversity of the mitochondrial control region to characterize the genetic structure of this species from forests and bushy areas of seven populations from Argentina and four populations from Chile. Statistical analyses showed shallow haplotype trees and mismatch distributions compatible with recent range expansions. The presence of “private” haplotypes indicates that current levels of gene flow among populations of each country would be low to moderate. Significant differences in haplotype frequencies were detected between eastern and western populations, indicating that the Andes mountains would be an effective geographic barrier for gene flow despite the existing valleys that could act as corridors for dispersion. A single clade containing all the haplotypes was recovered in the phylogenetic trees, suggesting postglacial dispersion from a single refugium during the Last Glacial Maximum. The higher effective size and levels of polymorphism in populations from Chile suggest that the refugium was located in this country. The asymmetric gene flow from Chile to Argentina may reflect a recent colonization of the eastern populations.

Le rongeur Oligoryzomys longicaudatus (Bennett, 1832) (Rodentia, Cricetidae) habite les forêts du sud de l’Argentine et du Chili, une région fortement affectée par les glaciations durant les périodes du pléistocène et de l’holocène. Nous évaluons la diversité de la région mitochondriale de contrôle afin de caractériser la structure génétique de cette espèce chez sept populations argentines et quatre populations chiliennes habitant des forêts et des régions arbustives. Les analyses statistiques révèlent des arbres d’haplotypes à branches courtes et des distributions mal assorties compatibles avec les expansions récentes d’aires de répartition. La présence d’haplotypes « privés » indique que les niveaux actuels de flux génique entre les populations des deux pays doivent être bas à modérés. Nous décelons des différences significatives dans les fréquences des haplotypes entre les populations de l’est et de l’ouest, ce qui indique que les Andes semblent former une barrière géographique effective, malgré l’existence de vallées qui pourraient servir de corridors de dispersion. Un clade unique regroupant tous les haplotypes se retrouve dans les arbres phylogénétiques, ce qui laisse croire à une dispersion postglaciaire à partir d’un refuge unique pendant le dernier maximum glaciaire. La taille effective et les degrés de polymorphisme plus élevés au Chili laissent croire que le refuge se situait dans ce pays. Le flux génique asymétrique du Chili vers l’Argentine peut être le reflet d’une colonisation récente de la population orientale.

Document Type: Research Article

Publication date: January 1, 2010

More about this publication?
  • Published since 1929, this monthly journal reports on primary research contributed by respected international scientists in the broad field of zoology, including behaviour, biochemistry and physiology, developmental biology, ecology, genetics, morphology and ultrastructure, parasitology and pathology, and systematics and evolution. It also invites experts to submit review articles on topics of current interest.
  • Information for Authors
  • Submit a Paper
  • Subscribe to this Title
  • Terms & Conditions
  • Sample Issue
  • Reprints & Permissions
  • ingentaconnect is not responsible for the content or availability of external websites

Tools

Favourites

Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more