Secondary contact zone: sympatry between two species of Drosophila

Abstract

Recent sympatry between species permits the study of important fenomena from the evolutionary process, for example: hybridization, introgression, adaptation and reinforcement. The sympatry zone between the cactophilic species Drosophila serido and D. antonietae represents a good model for researches of this nature, because there are phylogeographic hipoteses for its formation. The present project aims to analyse the structure and spatial and temporal dynamics of sympatric populations of D. serido and D. antonietae, at Santa Catarina Island, and at the region described as a contact zone for these two species. The population dynamics will be evaluated through periodic collections and the emergence of cacti. All individuals will be identified by the enzymatic marker isocitrate dehydrogenase (IDH), and male specimens will be used in genetic (microsatellite DNA) and morphological analyses (wing and terminalia morphometrics). The results will contribute to the characterization of this sympatry zone.