Fitness and competitive ability in irradiated populations of Drosophila melanogaster

Effects of Radiation on Populations of Drosophila Melanogaster with Different Genetic Structures I. Changes in Fitness and Productivity

“…As mentioned in earlier papers (e.g. Dyer 1966), 45% dominant lethals are induced among the straw flies prior to gene flow and it has also previously been shown (Dyer 1969a) that approximately 60% recessive lethals with a rate of allelism of about 15% will give rise to approximately 10% genetic deaths at each generation. Since there are, therefore, only about half the possible number of straw flies actually hatching, the contribution from the extra heterozygotes will be effectively doubled in proportionate terms, i.e.…”

“…The most important result, though, was that all four cages showed the same pattern of behaviour in the number and proportion of heterozygotes emerging. It has already been shown (Dyer 1966) that there was a significant fall in the proportion of heterozygotes emerging over these 12 generations in cage OR. …”

CHANGES IN FREQUENCY AND ALLELISM OF RECESSIVE LETHALS IN EXPERIMENTAL POPULATIONS OF <i>DROSOPHILA</i> <i>MELANOGASTER</i> WITH RADIATION HISTORIES

“…Among those experimental conditions the dose rate and the germ cell stages at which the radiation was administered must be principal factors to interprete the difference of the results obtained in the present and the previous experiments. Tobari and Murata (1970) have already pointed out that there might be some difference between lethals in the chronically irradiated population and in the acutely irradiated one; that is, according to Nei (1969), heterozygous effect of lethals was estimated to be 0.022 for the Wallace's populations (Prout 1954) which were chronically irradiated with 5R/hr, while it was 0.058 for Dyer's population (Dyer 1966) in which only the male flies were acutely irradiated with 546R/min.…”