THE ECO-GENETICS OF DROSOPHILA: Variations in Phenotypic traits

Clinal variation in morphometric traits of D. malerkotliana collected at four different altitudes of Chamundi hill and in some geographical populations was studied. The interesting feature of this study is that with the increase in altitude there was a progressive increase in some metric traits in males, not in female. Male size increases with altitude. In females although differences exit in these traits at different altitudes, there was no specific trend. The absence of clinal variation in the metric traits in females suggests that they are more heterogeneous than males. Correlative studies were made between male size and remating success in D. malerkotliana collected from 4 different geographical populations. Correlation matrix calculated for male size, male remating latency, male remating ability and percentage of remating frequency showed that in all geographic populations, the male size is negatively correlated with male remating latency, larger males remated more rapidly, more frequently, copulated longer time, inseminated a more number females. This study confirms the hypothesis "bigger is better"(Hegde 1997).