Phenotypic and genotypic structure of a natural Drosophila population for meristic morphologic characters and its seasonal changes

A natural population of Drosophila was genetically heterogeneous in the number of sternopleural bristles and the number of arista branches. In the summer, these characters had a low mean value and high coefficient of variation: in autumn, this relationship was reversed; in late spring, the values of the mean and coefficient of variation were intermediate. The dynamics of the character mean was determined by changes in phenotypic and genotypic composition of the population, which was examined during different seasons of the year. On average, the number of sternopleural bristles was higher, and the number of arista branches was lower in females than in males. The number of sternopleural bristles exhibited a higher phenotypic and genotypic variation than the number of arista branches.