Population genetics of Drosophila nasuta nasuta, Drosophila nasuta albomicana and their hybrids. I. Karyotypic mosaicism in the hybrid populations

D. n. nasuta and D. n. albomicana constitute a pair of chromosomal races with 2n=8 and 2n=6, respectively. The F1 of these has 2n=7 and it is fertile. There exists a state of karyotypic mosaicism as evidenced by the presence of 26 types of chromosome combinations in F2, F3 and F10 populations. In the midst of this karyotypic noise, the karyotype similar to that of F1 reached 51% of the population. Implications of these findings are discussed

Studies on the ontogenetic changes in the isozymes in Drosophila nasuta nasuta and Drosophila sulfurigaster neonasuta

Ontogenetic manifestations of four isozymes namely, acid phosphatase, alkaline phosphatase, α-esterase and β-esterase have been analysed in two closely related species- D. nasuta nasuta and D. sulfurigaster neonasuta. By adopting polyacrylamide gel electrophoretic technique 15 different developmental stages have been assayed. Electrophoretically homologous and distinct enzyme phenotypes for each enzyme system have been recognised in the two species under study. The implications of these findings are discussed

Pattern of adult eclosion during interspecific competition

During interspecific competition, eggs of the same age, of 2 different species, experience different speeds of development. In each mixed culture there exist 2 different peaks of adult emergence. Here is a mechanism ensuring that the maximum number of one of the competing species emerges first followed by the other. The possible implications of this are discussed