tailieunhanh - Báo cáo khoa học: Genetic properties of North African Drosophila melanogaster and comparison with European and Afrotropical populations

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Genetic properties of North African Drosophila melanogaster and comparison with European and Afrotropical populations | Génét. Sél. Evol. 1983 15 2 185-200 Genetic properties of North African Drosophila melanogaster and comparison with European and Afrotropical populations p. CAPY . DAVID R. ALLEMAND p. HYYTIA and J. ROUAULT . Laboratoire de Biologie et GẾnétique évolutives F 91190 Gif-sur-Yvette Laboratoire de Biologie des Populations Université Claude Bernard F 69622 Villeurbanne Summary Four kinds of genetic traits . allozyme frequencies six biometrical characters ethanol tolerance and oviposition rhythm which all exhibit latitudinal clines were measured in a Tunisian population. Allozymes and morphology were also studied in an Egyptian population The data were compared with those obtained for European and Afrotropical flies and also with a Seychellian population recently introduced in this archipelago. In all cases the morphology was studied on the second laboratory generation of isofemale lines. North African flies were found to be very close to European flies for allozyme frequencies and ethanol tolerance but very close to Afrotropical flies for ovariole number wing and thorax lengths. For other traits such as adult weight number of sternopleural chaetae and oviposition rhythm the North African flies were intermediate to those from Europe and Tropical Africa while for the number of abdominal chaetae the North African flies were superior to both of the other populations. Such observations demonstrate that significant local genetic divergences may be superimposed to the general tendency of the latitudinal cline. In spite of their tropical habitat the Seychellian flies were found to be very similar to those living in a temperate country and for all morphological traits a striking similarity was observed with the North African populations. It is however not yet possible to suggest a definitive answer for the origin of this introduced population. Key words Drosophila melanogaster ecological genetics geographic races latitudinal clines. Resume Caractéristiques .