Latitudinal allozymic variability in natural populations of Zaprionus indianus from India.

Twelve natural populations of Z. indianus from India, collected along lines of latitude, were analyzed electrophoretically and the geographical pattern of variation was compared at 15 allozyme loci. Except for Mdh-2, all the loci revealed extensive polymorphism. The allele frequency variation revealed a statistically significant correlation as well as regression coefficients with the latitude. The populations revealed extensive clinical variation at all the polymorphic loci, which depicted moderate to higher FST values. Thus, the observed genetic divergence in colonizing populations of Z. indianus shows the role of natural selection that varies spatially along the north-south axis of the Indian subcontinent.