Asymmetric allelic introgression across a hybrid zone of the coal tit (Periparus ater) in the central Himalayas
Päckert, Martin et al. (2022), Asymmetric allelic introgression across a hybrid zone of the coal tit (Periparus ater) in the central Himalayas, Dryad, Dataset, https://doi.org/10.5061/dryad.0gb5mkm28
In the Himalayas, a number of secondary contact zones have been described for vicariant vertebrate taxa. However, analyses of genetic divergence and admixture are missing for most of these examples. In this study, we provide a population genetic analysis for the coal tit (Periparus ater) hybrid zone in Nepal. Intermediate phenotypes between the distinctive western ‘spot-winged tit’ (P. a. melanolophus) andastern Himalayan coal tits (P. a. aemodius) occur across a narrow range of less than 100 km in western Nepal. As a peculiarity, another distinctive cinnamon-bellied form is known from a single population so far. Genetic admixture of western and eastern mitochondrial lineages was restricted to the narrow zone of phenotypically intermediate populations. The cline width was estimated 46 km only with a center close to the population of the cinnamon-bellied phenotype. In contrast, allelic introgression of microsatellite loci was asymmetrical from eastern P. a. aemodius into far western populations of phenotypic P. a. melanolophus but not vice versa. Accordingly, the microsatellite cline was about 3.7 times wider than the mitochondrial one.
A 437-bp long fragment of the mitochondrial control region was amplified from DNA extracts inferred from toe-pad samples of 50-year-old museum specimens and sequenced on a 16-column ABI 3130xl capillary sequencer (Applied Biosystems™). For the same samples a set of 10 microsatellite loci was analysed in two separate muliplex sets using the Type‐it® Microsatellite PCR Kit (Qiagen). Fragment-length analysis was performed on the same ABI 3130xl capillary sequencer for total volumes of 10 µl containing 1 µl muliplex PCR products.
Deutscher Akademischer Austauschdienst