The two sibling species of fruit fly, Drosophila melanogaster and D. simulans (Diptera: Drosophilidae), have long been used as the key model organisms in ecological and evolutionary research. While numerous studies have investigated the thermal responses of these two species, no study has yet systematically compared their response to dietary macronutrient balance. To fill this knowledge gap, we compared how various life-history traits expressed during larval development would response to an array of dietary ratio of protein to carbohydrate (P:C ratio) in these two sibling species. Largely consistent with previous studies, D. melanogaster took longer to complete their larval development and were much larger at adult emergence than D. simulans. For both species, an increase in dietary P:C ratio resulted in improved larval survivorship and faster development. However, the two species showed qualitatively different response to dietary P:C ratio when body mass at adult eclosion was concerned. The body mass of D. melanogaster peaked at an optimal P:C ratio of 1:4, but decreased as the P:C ratio either increased or decreased from this optimum. In marked contrast, the body mass of D. simulans was insensitive to dietary P:C ratio.

Drosophila melanogaster(OR)와 D. simulans(09) 및 그들 종간 잡종 사이의 형태적 유연관계를 비교하기 위하여 내.외부생식기 및 성즐을 조사하였다. 이를 위하여 D. melanogaster 암컷과 D. simulans 수컷의 교배에서 암컷을, 그 정역 교배로서 수컷을 얻었으며 두 종간 사이의 잡종 들은 모두 불임이었다. 내부생식기의 비교에서, 두종간 (melanogaster female simulans male) 잡종 { 암컷의 경우는 양쪽 난소가 모두 퇴화된 형태였으며, 그 정역교배에 의한 수컷의 정소는 미발달된 상태로 남아 있었다. 이런 형태적 특징은 D. melanogaster P-M system에서의 hybrid dysgensesis에 의한 양상과 매우 유사하였다. 수컷의 앞다리 제1부절에 존재하는 성즐의 평균 치열수는 D. melanogaster와 D. simulans에서 각각 10.73개와 8.35개 였으며, 잡종 수컷의 경우는 9.97개 정도였다. 두 종간 잡종 수컷의 외부 생식기의 전체적인 형태는 D. melanogaster와 비슷하였으나, 부분적으로 D. simulans에 유사하거나 중간적인 형질을 가지는 mosaic 구조였다

Physiological toxic and mutagenic effects of gramoxone in Drosophila melanogaster were invetigated. Gramoxone was highly toxic on the development, resulting in of lowering the viability and in prolongation of the developmental times. Adults treated with gramoxone during the developmental stages caused a lowering of the productivity and a little change in protein quantity. But the effect on the sex-linked lethal mutagenesis was found to be negative. The order of mortality causing adult stage feeding to gramoxone in the D. melanogaster complex was like this ; D. mauritiana, D. sechellia, D. simulans and D. melanogaster. Two species of the D. yakuba complex were alike. Those results were more or less correlation with speciation of the D. melanogaster subgroup.