The plastic fly: the effect of sustained fluctuations in adult food supply on life history traits

Many adult traits in Drosophila melanogaster show phenotypic plasticity, and the effects of diet on traits such as lifespan and reproduction are well explored. Although plasticity in response to food is still present in older flies, it is unknown how sustained environmental variation affects life-history traits. Here, we explore how such life-long fluctuations of food supply affect weight and survival in groups of flies and affect weight, survival and reproduction in individual flies. In both experiments, we kept adults on constant high or low food and compared these to flies that experienced fluctuations of food either once or twice a week. For these ‘yoyo’ groups, the initial food level and the duration of the dietary variation differed during adulthood, creating four ‘yoyo’ fly groups. In groups of flies, survival and weight were affected by adult food. However, for individuals, survival and reproduction, but not weight, were affected by adult food, indicating that single and group h...

黑腹果蝇（Drosophila melanogaster）的诸多成虫性状均表现出表型可塑性（phenotypic plasticity），膳食对寿命、繁殖等性状的影响已得到充分研究。尽管老龄果蝇仍存在对食物的响应可塑性，但目前尚不清楚持续的环境变化如何影响其生活史性状（life-history traits）。本研究旨在探究这种食物供给的终身波动如何影响果蝇群体的体重与存活情况，以及个体果蝇的体重、存活与繁殖能力。在两项实验中，我们将成虫饲养于恒定高膳食或低膳食环境中，并将其与每周经历一次或两次膳食波动的果蝇进行对照。此类“悠悠球”组在成虫期的初始膳食水平与膳食变化的时长存在差异，由此形成了四组“悠悠球”果蝇群体。在果蝇群体中，成虫期的膳食会影响其存活情况与体重。然而对于个体果蝇而言，成虫期膳食仅影响其存活与繁殖能力，而非体重，这表明单只个体与群体的