Evolution and Ecophysiology Group, Department of Functional and Evolutionary Entomology, Gembloux Agro-Bio Tech, University of Liège, Passage des Déportés 2, 5030, Gembloux, Belgium.
Evolutionary Ecology and Genetics Group, Earth and Life Institute, UCLouvain, Croix du Sud 4-5, 1348, Louvain-la-Neuve, Belgium.
Sci Rep. 2022 Jul 27;12(1):12855. doi: 10.1038/s41598-022-15325-0.
In arthropods, larger individuals tend to have more fat reserves, but data for many taxa are still missing. For the vinegar fly Drosophila melanogaster, only few studies have provided experimental data linking body size to fat content. This is rather surprising considering the widespread use of D. melanogaster as a model system in biology. Here, we hypothesized that fat content in D. melanogaster is positively correlated with body size. To test this, we manipulated the developmental environment of D. melanogaster by decreasing food availability. We then measured pupal size and quantified fat content of laboratory-reared D. melanogaster. We subsequently measured pupal size and fat content of several field-caught Drosophila species. Starvation, crowding, and reduced nutrient content led to smaller laboratory-reared pupae that contained less fat. Pupal size was indeed found to be positively correlated with fat content. The same correlation was found for field-caught Drosophila pupae belonging to different species. As fat reserves are often strongly linked to fitness in insects, further knowledge on the relationship between body size and fat content can provide important information for studies on insect ecology and physiology.
在节肢动物中，较大的个体往往具有更多的脂肪储备，但许多类群的数据仍然缺失。对于醋蝇黑腹果蝇来说，只有少数研究提供了将体型与脂肪含量联系起来的实验数据。考虑到黑腹果蝇作为生物学模型系统的广泛应用，这是相当令人惊讶的。在这里，我们假设黑腹果蝇的脂肪含量与体型呈正相关。为了验证这一点，我们通过减少食物供应来操纵黑腹果蝇的发育环境。然后，我们测量了实验室饲养的黑腹果蝇的蛹体大小并量化了脂肪含量。随后，我们测量了几个野外捕获的果蝇物种的蛹体大小和脂肪含量。饥饿、拥挤和营养物质含量降低导致实验室饲养的蛹体变小，脂肪含量减少。确实发现蛹体大小与脂肪含量呈正相关。属于不同物种的野外捕获的果蝇蛹体也存在相同的相关性。由于脂肪储备通常与昆虫的适应性密切相关，因此，关于体型和脂肪含量之间关系的进一步知识可以为昆虫生态学和生理学的研究提供重要信息。
