Open AccessGenetic analysis of a contact zone between two lineages of the ocellated lizard ( Lacerta lepida Daudin 1802) in south‐eastern I beria reveal a steep and narrow hybrid zone
Author(s) -
Miraldo Andreia,
Faria Christiana,
Hewitt Godfrey M.,
Paulo Octavio S.,
Emerson Brent C.
Publication year - 2013
Publication title -
journal of zoological systematics and evolutionary research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.769
H-Index - 50
eISSN - 1439-0469
pISSN - 0947-5745
DOI - 10.1111/jzs.12005
Subject(s) - biology , hybrid zone , subspecies , gene flow , reproductive isolation , allopatric speciation , lizard , zoology , range (aeronautics) , contact zone , population , evolutionary biology , ecology , genetic variation , gene , genetics , history , ethnology , demography , materials science , sociology , composite material
Measuring the diffusion of genes between diverging taxa through zones of secondary contact is an essential step to understand the extent and nature of the reproductive isolation that has been achieved. Previous studies have shown that the ocellated lizard ( L acerta lepida D audin, 1802) has endured repeated range fragmentation associated with the climatic oscillations of the P lio‐ P leistocene that promoted diversification of many different evolutionary units within the species. However, the oldest divergence within the group is estimated to have occurred much earlier, during the M iocene, around 9 Ma and corresponds to the split between the subspecies L acerta lepida nevadensis B uchholz (1963) and L acerta lepida lepida D audin (1802). Although these two evolutionary units have documented genetic and morphological differentiation, most probably accumulated during periods of allopatry, little is known about patterns of gene flow between them. In this study, we performed a population genetic analysis of a putative area of secondary contact between these two taxa, using mt DNA and microsatellite data. We assessed levels of gene flow across the contact zone to clarify to what extent gene flow may be occurring. Hybridization between the subspecies was observed by the presence of genetically introgressed individuals. However, the overall coincidence of mitochondrial and multilocus nuclear clines and generally steep clines support the idea that this contact zone is acting as a barrier to gene flow. Taken together, these results suggest that L . l. lepida and L . l. nevadensis are in independent evolutionary trajectories and should be considered as two different species.