LTREB: Social, Environmental, and Evolutionary Dynamics of Replicated Hybrid Zones in Swordtails (Teleostei: Xiphophorus) of Mexico's Sierra Madre Oriental

对自然杂交——物种间遗传信息的交换——的研究是进一步了解基因如何在生物体和环境中发挥作用的基础。杂交——不同物种之间的杂交——还可用于识别与感兴趣的性状相关的特定基因，以及这些基因如何与环境变化相互作用，最终揭示疾病的遗传基础和对环境变化的适应。剑尾鱼是一种长期存在的遗传学、生理学和行为学模型，本项目研究了剑尾鱼的自然种群和实验种群在10年内行为决策、通信信号、耐热性和耐寒性以及种群结构的变化。两种亲本分布在高海拔和低海拔，杂交分布在中等海拔。实验种群将沿海拔梯度播种第一代杂交品种。在高海拔地区，与耐寒性相关的基因将随着高海拔物种的交流信号和行为偏见而传播，而在低海拔地区反之亦然。这项研究将确定与决策、沟通和耐温性有关的新基因，这可能会导致在医学和农业上的应用。此外，这些数据将解决基因组中哪些特定的、可识别的部分负责适应各种环境的程度。数据的收集和分析将通过本科生和当地K-12学生之间的结构化夏季指导计划来完成。由于这项研究的长期性，K-12学员将有机会在项目后期成为导师。

The study of natural hybridization - the exchange of genetic information between species - is fundamental to further understanding how genes function within organisms and within the environment. Hybrids - crosses between different species - can also be used to identify specific genes associated with traits of interest and how these genes interact with environmental variation, ultimately shedding light on the genetic basis of disease and adaptation to environmental change. This project studies changes in behavioral decisions, communication signals, heat and cold tolerance, and population structure over 10 years in natural and experimental populations of swordtail fish, a longstanding model in genetics, physiology, and behavior. The two parent species are found at high and low elevations, hybrids at intermediate elevations. Experimental populations will seed first-generation hybrids along an elevation gradient. The predicted response at the high elevation site is that genes associated with cold tolerance will spread along with the communication signals and behavioral biases of the high-elevation species, and vice-versa at the low elevation site. The study will identify novel genes involved with decision-making, communication, and temperature tolerance, which may lead to applications in medicine and agriculture. Further, the data will address the extent to which specific, identifiable parts of the genome are responsible for adaptation to various environments. Collection and analysis of data will be accomplished with a structured summer mentorship program between undergraduate students and local K-12 students. Because of the long-term nature of the study, K-12 trainees will have the opportunity to become mentors themselves later in the project.