Open AccessGenetic and Karyotypic Structure of a Hybrid Zone Between the Chromosomal Races Cordon and Valais in the Common Shrew, Sorex Araneus
Author(s) -
Brüunner Harald,
Hausser Jacques
Publication year - 1996
Publication title -
hereditas
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.819
H-Index - 50
eISSN - 1601-5223
pISSN - 0018-0661
DOI - 10.1111/j.1601-5223.1996.00147.x
Subject(s) - sorex , biology , hybrid zone , assortative mating , evolutionary biology , araneus , hybrid , genetics , population , shrew , zoology , mating , genetic variation , gene flow , gene , botany , demography , sociology
Hybrid zones between genetically differentiated populations provide material to study evolutionary processes. Since the discovery of chromosomal races in Sorex aruneus , contact zones have attracted attention of scientists. So far, studies on genetic markers in Sorex hybrid zones are missing. The acrocentric chromosomal race Cordon and the highly metacentric race Valais meet and hybridize at Les Houches in the Western Alps. On a transect through the hybrid zone, 273 shrews were caught at 15 localities over 4 years. Karyotype as well as the nuclear protein loci Alb and Pg were analyzed. F st and F is values were calculated by F ‐statistics. An analysis on pooled samples revealed the genetical differences between the hybridizing races as the only cause of population structuring. Genetical markers show clines with very strong frequency shifts at a mountain torrent, but behave differently through the zone. The performance of the torrent in maintaining the hybrid zone, selection against hybrids, possible assortative mating and linkage of the Valais Pg allele to a diagnostic chromosome arm, are discussed.