Variation in complex mating signals in an "island" hybrid zone between Stenobothrus grasshopper species.

ABSTRACT: Two grasshopper species Stenobothrus rubicundus and S. clavatus were previously shown to meet in a narrow hybrid zone on Mount Tomaros in northern Greece. The species are remarkable for their complex courtship songs accompanied by conspicuous movements of antennae and wings. We analyzed variations in forewing morphology, antenna shape, and courtship song across the hybrid zone using a geographic information system, and we documented three contact zones on Mount Tomaros. All male traits and female wings show abrupt transitions across the contact zones, suggesting that these traits are driven by selection rather than by drift. Male clines in antennae are displaced toward S. clavatus, whereas all clines in wings are displaced toward S. rubicundus. We explain cline discordance as depending on

SUBMITTER: Sradnick J 

PROVIDER: S-EPMC4979727 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature