Present address: Metapopulation Research Group, University of Helsinki, Department of Biological and Environmental Sciences, P.O. Box 65, 00014 Helsinki, Finland.
Numts help to reconstruct the demographic history of the ocellated lizard (Lacerta lepida) in a secondary contact zone
Article first published online: 4 JAN 2012
© 2012 Blackwell Publishing Ltd
Volume 21, Issue 4, pages 1005–1018, February 2012
How to Cite
MIRALDO, A., HEWITT, G. M., DEAR, P. H., PAULO, O. S. and EMERSON, B. C. (2012), Numts help to reconstruct the demographic history of the ocellated lizard (Lacerta lepida) in a secondary contact zone. Molecular Ecology, 21: 1005–1018. doi: 10.1111/j.1365-294X.2011.05422.x
- Issue published online: 24 JAN 2012
- Article first published online: 4 JAN 2012
- Received 20 July 2010; revision received 16 November 2011; accepted 23 November 2011
- secondary contact zone
In northwestern Iberia, two largely allopatric Lacerta lepida mitochondrial lineages occur, L5 occurring to the south of Douro River and L3 to the north, with a zone of putative secondary contact in the region of the Douro River valley. Cytochrome b sequence chromatograms with polymorphisms at nucleotide sites diagnostic for the two lineages were detected in individuals in the region of the Douro River and further north within the range of L3. We show that these polymorphisms are caused by the presence of four different numts (I–IV) co-occurring with the L3 genome, together with low levels of heteroplasmy. Two of the numts (I and II) are similar to the mitochondrial genome of L5 but are quite divergent from the mitochondrial genome of L3 where they occur. We show that these numts are derived from the mitochondrial genome of L5 and were incorporated in L3 through hybridization at the time of secondary contact between the lineages. The additional incidence of these numts to the north of the putative contact zone is consistent with an earlier postglacial northward range expansion of L5, preceding that of L3. We show that genetic exchange between the lineages responsible for the origin of these numts in L3 after secondary contact occurred prior to, or coincident with, the northward expansion of L3. This study shows that, in the context of phylogeographic analysis, numts can provide evidence for past demographic events and can be useful tools for the reconstruction of complex evolutionary histories.