Populations found at the edge of a species range often have decreased genetic diversity, which together with high gene flow may reduce the ability of a species to adapt to local environmental conditions. The Dead Sea Sparrow Passer moabiticus occupies a disjointed range, where the Israeli populations are considered peripheral and fragmented. The species is also thought to have undergone a recent range expansion. We aimed to describe the genetic and morphological variation of the Israeli populations and to determine the extent of gene flow among them. We expected that because of the small latitudinal gradient across Israel and the recent range expansion of the species that Dead Sea Sparrow populations would show no significant morphological adaptation to local environmental conditions, and that considerable gene flow would be taking place among populations. Our findings indicate the existence of gene flow, suggesting high connectivity among populations, but recovered no support for a recent range expansion, possibly due to insufficient time since expansion for mutations to have accumulated. However, despite recurrent gene flow among populations, latitudinal variation in wing length (male and female) and body mass (male) was indicative of local adaptation across Israel, in accordance with Bergmann's rule.
|Number of pages||13|
|State||Published - 1 Jul 2019|
Bibliographical noteFunding Information:
The authors would like to thank S. Ben Cohen for field assistance and comments on the manuscript; The Natural History Museum at Tring, especially acting senior curator M. Adams; The American Museum of Natural History in New York, for enabling access to invaluable specimens; and Y. Kiat from the The Israeli Bird Ringing Centre (IBRC) of the Society for the Protection of Nature in Israel (SPNI). We thank Yang Liu, Rauri Bowie and three anonymous reviewers for their constructive comments. We thank N. Paz for help with English editing. This research was partially supported by the Israel Nature and Parks Authority. This research received support from the SYNTHESYS Project (http://www.synthesys.info/), which is financed by European Community Research Infrastructure Action under the FP7 ?Capacities? Programme and a Collection Study Grant (American Museum of Natural History).
© 2018 British Ornithologists' Union
- gene flow
- genetic diversity
- peripheral populations
- phenotypic variation
- population structure
- range expansion