Natural selection and the reinforcement of mate recognition

Natural selection on mate recognition may often contribute to speciation, r esulting in reproductive character displacement. Field populations of Droso phila serrata display reproductive character displacement in cuticular hydr ocarbons when sympatric with Drosophila birchii. We exposed field sympatric and allopatric populations of D. serrata to experimental sympatry with D. birchii for nine generations. Cuticular hydrocarbons of field allopatric D. serrata populations evolved to resemble the field sympatric populations, w hereas field sympatric D. serrata populations remained unchanged. Our exper iment indicates that natural selection on mate recognition resulted in the field pattern of reproductive character displacement.