This multi-day exercise is designed for a college Genetics and Evolution laboratory to demonstrate concepts of inheritance and phenotypic and molecular evolution using a live model organism, Drosophila simulans. Students set up an experimental fruit fly population consisting of ten white eyed flies and one red eyed fly. Having red eyes is advantageous compared to having white eyes, allowing students to track the spread of this advantageous trait over several generations. Ultimately, the students perform PCR and gel electrophoresis at two neutral markers, one located in close proximity to the eye-color locus, and one located at the other end of the chromosome. Students observe that most flies have red eyes, and these red-eyed flies have lost variation at the near marker, but maintained variation at the far marker, hence observing a "selective sweep" and the "hitchhiking" of a nearby neutral variant. Students literally observe phenotypic and molecular evolution in their classroom!

中文翻译：

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见证果蝇的表型和分子进化。

这个为期多天的练习是为大学遗传学和进化实验室设计的，目的是使用活的模式生物果蝇模拟来展示遗传、表型和分子进化的概念。学生们建立了一个实验果蝇种群，由 10 只白眼蝇和一只红眼蝇组成。与白眼相比，红眼更有优势，让学生可以追踪这种优势特征在几代人中的传播。最终，学生们对两个中性标记进行 PCR 和凝胶电泳，一个位于靠近眼睛颜色基因座的位置，一个位于染色体的另一端。学生观察到大多数苍蝇的眼睛是红的，这些红眼苍蝇在近处失去了变异，但在远处保持了变异，因此观察到“