Genetic analysis of a contact zone between two lineages of the ocellated lizard (Lacerta lepida Daudin 1802) in south-eastern Iberia reveal a steep and narrow hybrid zone

Measuring the diffusion of genes between diverging taxa through zones of secondary contact is an essential step to understand the extent and nature ofthe reproductive isolation that has been achieved. Previous studies have shown that the ocellated lizard (Lacerta lepidaDaudin, 1802) has enduredrepeated range fragmentation associated with the climatic oscillations of the Plio-Pleistocene that promoted diversification of many different evolution-ary units within the species. However, the oldest divergence within the group is estimated to have occurred much earlier, during the Miocene, around9 Ma and corresponds to the split between the subspeciesLacerta lepida nevadensisBuchholz (1963) andLacerta lepida lepidaDaudin (1802).Although these two evolutionary units have documented genetic and morphological differentiation, most probably accumulated during periods of allop-atry, little is known about patterns of geneflow between them. In this study, we performed a population genetic analysis of a putative area of second-ary contact between these two taxa, using mtDNA and microsatellite data. We assessed levels of geneflow across the contact zone to clarify to whatextent geneflow may be occurring. Hybridization between the subspecies was observed by the presence of genetically introgressed individuals. How-ever, the overall coincidence of mitochondrial and multilocus nuclear clines and generally steep clines support the idea that this contact zone is actingas a barrier to geneflow. Taken together, these results suggest thatL. l. lepidaandL. l. nevadensisare in independent evolutionary trajectories andshould be considered as two different species.

Bibliographic Details

Main Authors:	Miraldo, Andreia, Faria, Cristina, Hewitt, Godfrey M, Paulo, Octavio S., Emerson, Brent C.
Other Authors:	Fundação para a Ciência e a Tecnologia (Portugal)
Format:	artículo biblioteca
Language:	English
Published:	Blackwell Publishing 2012-10-22
Subjects:	Hybrid Zone, Lacerta Lepida, Speciation, Geneflow,
Online Access:	http://hdl.handle.net/10261/178546 http://dx.doi.org/10.13039/501100001871 http://dx.doi.org/10.13039/501100011011
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