Data from: Desiccation resistance and mating behavior in laboratory populations of Drosophila simulans originating from the opposing slopes of Lower Nahal Oren (Israel)

Lower Nahal Oren in Northern Israel, often referred to as "Evolution Canyon", has been proposed as a microscale model site for ecological evolution. However, conflicting mating assay and stress-resistance contribute to controversy over the Nahal Oren model. In this study we further tested the Nahal Oren model, while extending its focus from Drosophila melanogaster to its sister species, D. simulans. Using fly populations derived from the opposing canyon slopes and acclimated to laboratory conditions for 11-22 generations we did not find a significant slope effect on desiccation resistance (p=0.96) or body metabolic fuel content (p>0.43) which would indicate a genetic basis for adaptation to local resource limitation. Multiple-choice mating assays (47-48% homotypic couples in two replicate populations) did not indicate divergence from a random mating pattern between north and south-facing slope flies. In conclusion, our findings do not support divergence of D. simulans populations across Lower Nahal Oren.

以色列北部下纳哈尔奥伦河谷（Lower Nahal Oren）常被称为‘进化峡谷（Evolution Canyon）’，已被提议作为生态进化研究的微观尺度模型位点。然而，相互矛盾的交配实验与抗逆性研究结果，使得纳哈尔奥伦模型存在诸多争议。本研究进一步验证了纳哈尔奥伦模型，同时将研究对象从黑腹果蝇（Drosophila melanogaster）拓展至其近缘物种拟暗果蝇（Drosophila simulans）。我们使用源自峡谷对立坡面、且在实验室条件下驯化11-22代的果蝇种群开展实验，未发现坡面对果蝇抗干燥性（p=0.96）或机体代谢底物含量（p>0.43）存在显著影响——而这类影响本应能反映适应本地资源限制的遗传基础。多选交配实验结果（两个重复种群中同型配偶占比为47%~48%）未表明北向坡面与南向坡面的果蝇之间存在偏离随机交配模式的分化。综上，本研究结果不支持下纳哈尔奥伦河谷拟暗果蝇种群存在分化。