The evolution of a highly speciose group in a changing environment: are we witnessing speciation in the Ibera wetlands?

Maria Jimena Gomez Fernandez*, Oscar E. Gaggiotti, Patricia Mirol

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

11 Citations (Scopus)

Abstract

Delimiting species is very conflicting in the case of very young taxa that are in the process of diversification, and even more difficult if the species inhabit a heterogeneous environment. In this case, even population delimitation is controversial. The South American genus of subterranean rodents Ctenomys is highly speciose, with 62 species that appeared in the lapse of 3 Myr. Within the genus, the perrensi group, formed by three named species and a group of forms of unknown taxonomic status, inhabits the Ibera wetland, in northern Argentina. Almost every locality shows a particular chromosomal complement. To understand the relationships and the evolutionary process among species and populations, we examined mitochondrial DNA sequences and microsatellite genotypes. We found an isolation-by-distance pattern with evidence of cluster-like behaviour of the system. The mitochondrial DNA network revealed two different groups, separated by one of the main rivers of the region. Clustering methods delimited 12 different populations and five metapopulation lineages that seem to be evolving independently. We found evidence of ancient migration among localities at the centre of the distribution but no signals of current migration among the 12 delimited clusters. Some of the genetic clusters found included localities with different chromosomal numbers, which points to the existence of gene flow despite chromosomal variation. The evolutionary future of these five lineages is controlled by the dynamics of their habitat: if stable, they may become distinct species; otherwise, they may collapse into a hybrid swarm, forming a single evolving metapopulation.

Original languageEnglish
Pages (from-to)3266-3282
Number of pages17
JournalMolecular Ecology
Volume21
Issue number13
DOIs
Publication statusPublished - Jul 2012

Keywords

  • DIVERSIFICATION
  • SEQUENCES
  • ESTEROS DEL IBERA
  • SUBTERRANEAN RODENT CTENOMYS
  • fragmented habitat
  • Ctenomys
  • OCTODONTIDAE
  • MULTILOCUS GENOTYPE DATA
  • POPULATION-STRUCTURE
  • speciation
  • BANDED KARYOTYPES
  • TUCOS GENUS CTENOMYS
  • metapopulation lineages
  • MITOCHONDRIAL

Fingerprint

Dive into the research topics of 'The evolution of a highly speciose group in a changing environment: are we witnessing speciation in the Ibera wetlands?'. Together they form a unique fingerprint.

Cite this