Variability of morphological traits in Drosophila bipectinata complex.

Phenotypic or morphological differences among different populations and sexual dimorphism in certain metric traits were analysed in D. bipectinata complex. It was noticed that different populations of D. bipectinata species group harbour large amount of variation for these characters. In all the populations, morphometric characters such as lengths of femur, tibia and wing length, wing width, number of sternopleural bristles and bristles on epandrium varied significantly among populations. The study indicates that the morphological variations are due to the interplay of genetic and environmental endowments. Further, females had significantly larger values, for lengths of femur, tibia and wing length, wing width and sternopleural bristles.

Lack of correlation between mating activity and EST-1 polymorphism in three natural and laboratory populations of Drosophila bipectinata.

Est-1 polymorphism and mating activity have been studied in three natural populations of D. bipectinata and after 10 generations of their maintenance in the laboratory. The results indicate that the enzyme Est-1 variation was not significant within natural populations within F10 generation and also between different natural populations and F10 generation indicating the role of balancing selection in the maintenance of enzyme polymorphism in both natural and laboratory conditions. On the other hand, there was variability in the mating activity within natural populations and within F10 generation and also between natural population and F10 generation. However, there was no correlation between Est-1 polymorphism and mating activity.

Correlative studies on mating speed and metric traits in Drosophila malerkotliana.

Relationship between mating speed, an important component of fitness, and morphological characters such as lengths of wing, femur, tibia and first tarsus have been analysed in D. malerkotliana. Flies mating first have longer wings and forelegs and mating flies have lower coefficient of variability in wing length than nonmating ones. Age seems to have no detectable effect on the relationship between these metric traits and mating speed.