Data from: Evolution under dietary restriction increases male reproductive performance without survival cost

Dietary restriction (DR), a reduction in nutrient intake without malnutrition, is the most reproducible way to extend lifespan in a wide range of organisms across the tree of life, yet the evolutionary underpinnings of the DR effect on lifespan are still widely debated. The leading theory suggests that this effect is adaptive and results from reallocation of resources from reproduction to somatic maintenance in order to survive periods of famine in nature. However, such response would cease to be adaptive when DR is chronic and animals are predicted to allocate more resources to reproduction. Nevertheless, chronic DR can also increase the strength of selection resulting in the evolution of more robust genotypes. We evolved Drosophila melanogaster fruitflies on ‘DR’, ‘standard’ and ‘high’ adult diets in replicate populations with overlapping generations. After ~25 generations of experimental evolution, male ‘DR’ flies had higher fitness than males from ‘standard’ and ‘high’ populations. Strikingly, this increase in reproductive success did not come at a cost to survival. Our results suggest that sustained DR selects for more robust male genotypes, which are overall better able to convert resources into energy, which they allocate mostly to reproduction.饮食限制（Dietary Restriction, DR）指在不造成营养不良的前提下减少营养摄入，是目前在生命之树涵盖的各类生物中，可重复实现的最有效寿命延长手段。然而，饮食限制对寿命产生影响的进化机制，目前仍存在广泛争议。主流理论认为，该效应具备适应性，源于资源从繁殖投入向体细胞维持的重新分配，以此帮助生物体在自然界的饥荒时期存活下来。然而，当饮食限制长期持续时，这类适应性响应将不再具备适应性，此时生物体理论上会将更多资源分配给繁殖活动。尽管如此，长期饮食限制也可增强选择压力，进而催生更具强健性的基因型演化。我们以具有重叠世代的重复种群为实验对象，让黑腹果蝇（Drosophila melanogaster）分别在‘饮食限制（DR）’‘标准饮食’和‘高营养饮食’的成虫饮食条件下进行实验演化。经过约25代的实验演化后，饮食限制组的雄性果蝇的适合度显著高于标准饮食组与高营养饮食组的雄性果蝇。值得注意的是，这种繁殖成功率的提升并未以生存能力的下降为代价。我们的研究结果表明，长期持续的饮食限制会筛选出更具强健性的雄性果蝇基因型，这类基因型整体上能够更高效地将资源转化为能量，并将大部分能量分配给繁殖活动。