Genetic polymorphism and its ecological background in tephritid populations ( Diptera: Tephritidae).

Abstract

Examined populations of Tephritis conura on Cirsium heterophyllum and C.oleraceum and Urophora cardui on C. arvense. Despite similar life histories and ecology, there were marked differences in the genetic structures of the tephritid populations, probably caused by different host ranges and different dispersal capacities. The morphospecies T. conura appears to consist of 2 sibling species or genetically distinct host races with different periods synchronised with their respective host plant species. U. cardui, however, shows no sign of a speciation process, possibly due to the high degree of specialisation and adaptation to a single host.-P.J. Jarvis