Testing hypotheses for genealogical discordance in a rainforest lizard
Date
2012
Authors
Singhal, Sonal
Moritz, Craig
Journal Title
Journal ISSN
Volume Title
Publisher
Blackwell Publishing Ltd
Abstract
Genealogical discordance, or when different genes tell distinct stories although they evolved under a shared history, often emerges from either coalescent stochasticity or introgression. In this study, we present a strong case of mito-nuclear genealogical discordance in the Australian rainforest lizard species complex of Saproscincus basiliscus and S. lewisi. One of the lineages that comprises this complex, the Southern S. basiliscus lineage, is deeply divergent at the mitochondrial genome but shows markedly less divergence at the nuclear genome. By placing our results in a comparative context and reconstructing the lineages' demography via multilocus and coalescent-based approximate Bayesian computation methods, we test hypotheses for how coalescent variance and introgression contribute to this pattern. These analyses suggest that the observed genealogical discordance likely results from introgression. Further, to generate such strong discordance, introgression probably acted in concert with other factors promoting asymmetric gene flow between the mitochondrial and nuclear genomes, such as selection or sex-biased dispersal. This study offers a framework for testing sources of genealogical discordance and suggests that historical introgression can be an important force shaping the genetic diversity of species and their populations.
Description
Keywords
Keywords: mitochondrial DNA; animal; article; Australia; Bayes theorem; biological model; cell nucleus; gene flow; genetics; lizard; mitochondrial genome; molecular genetics; multilocus sequence typing; nucleotide sequence; phylogeny; phylogeography; Animals; Austr approximate Bayesian computation; cytonuclear discordance; demographic reconstruction; introgression; phylogeography; Saproscincus basiliscus
Citation
Collections
Source
Molecular Ecology
Type
Journal article
Book Title
Entity type
Access Statement
License Rights
Restricted until
2037-12-31
Downloads
File
Description