초파리集團의 選擇利益에 관한 遺傳學的 硏究 = Genetic Study on the Selective Advantage in Populations of Drosophila melanogaster

다국어 초록 (Multilingual Abstract)

A study on the genetic behavior of sexually selective advantage between wild and visible mutant groups of Drosophila melanogaster was carried out. From nine Korean localities, wild type fruit flies, Drosophila melanogaster, were collected from early September to late October in 1987.
For the present experiment using population cages, each cage of nine localities in Korea and Ore-gon-R, ten cages in total, contained two groups of X-linked mutant fruit flies, m : miniature, y : yellow and wild type fruit flies sampled from different localities. Ten pairs of wild type, the miniature and the yellow respectively, were put into a cage, then thirty pairs per cage.
Having examined whether sexually selective advantage played among the different phenotypes. There were observed gene arrangement and genotype frequencies in every generation through twenty five successive generations. In all cases the frequency of the wild type increased and that of the mutant types declined, though at different rates in different populations.
In each population cage, the culture of Drosophila melanogaster were set up and contained the wild type flies collected from nine Korean localities and miniature and yellow mutant flies which have been feeding in the Laboratory room of Won-Kwang University. Although they were much alike in survival, the miniature female flies were not found at all from the culture after 1-15 generations. The miniature male flies were also eliminated in each population cage through eleven to sixteen generations. Through one to eight successive generations, the yellow female flies were eliminated and so did the yellow male flies through eleven to nineteen successive generations. In regard to this fact, the low efficiency of mutant flies in mating was suggested. All the females discriminated against the mutant males. It seemed reasonable to assume that such selective disadvantage was so effective to eliminate the "less fit" flies in a remarkably short span of time.
Environmental variables such as latitude and longitude were hypothesized to cause and interrelation ships between surrounding conditions and sexually selective advantage on +gene -bearing chromosome. The coast-to-inland cline and north-to-south cline in the western side of the Korean peninsula have been disclosed in the present study. And summarized are that, as to the gene frequencies of wild, miniature, yellow, and yellow-miniature of Drosophila melanogaster, the strength of selective advantage was varied due to localities. The wild type was the strongest in selective advantage and weakened in order of yellow-miniature, yellow and miniature.