Collaborative Research: Genetic variation as a driver of host and symbiont response to increased temperature on coral reefs

在珊瑚礁上，与单细胞藻类（共生菌）和珊瑚礁物种的共生关系从字面上和比喻上构成了珊瑚礁生态系统的基础。珊瑚礁是气候变化下最受威胁的生态系统之一，由于环境压力的增加，即温度的升高，珊瑚礁正在迅速减少。气候变化导致海洋温度升高，威胁到共生菌及其宿主之间的联系。在这个项目中，研究人员研究了共生菌的遗传多样性，以及这一重要物种随着温度的变化而进化的潜力。该项目还将研究共生菌种群的生态和进化动态是否会影响其宿主的表现。如果是这样的话，这就表明，在生态和经济上至关重要的珊瑚礁上，具有较短世代的微生物的进化可以使其适应较长寿的宿主物种。鉴于许多珊瑚礁的多样性已经丧失，考虑共生生物的进化变化将如何影响珊瑚礁物种，对于预测珊瑚礁对未来气候变化的反应至关重要。该项目为一所西班牙裔服务机构的两名研究生和几名本科生提供培训。这项工作包括通过尼亚加拉水族馆、当地K-12学校和基于网络的教育模块向学生和公众推广。进化对当代生态过程的影响是进化生态学研究的前沿。本项目将响应实验的需求，阐明遗传变异对共生菌性能的影响，以及对共生菌（宿主和共生体）对温度升高的响应的影响。这些实验通过生态和进化机制检查温度的影响，并将确定在复制的实验种群中适应和驯化的相对重要性。研究人员将研究一个物种（Symbiodinium antillogorgium）内的遗传变异如何影响共生生物在培养物和宿主中的表现，以及这如何影响共生生物对温度升高的反应。此外，该项目还研究了全息生物对与气候变化相关的温度升高的反应是否取决于特定的GxG宿主-共生体组合。此外，研究人员将研究共生历史对共生宿主的影响，这在生态进化研究中基本上被忽视了。这些实验为预测珊瑚礁上的无脊椎动物宿主是否会通过适应其共生体来应对全球变化提供了第一步。

On coral reefs, mutualisms with single celled algae (Symbiodinium) and reef species literally and figuratively form the foundation of reef ecosystems. Coral reefs are among the most threatened ecosystems under a changing climate and are rapidly declining due to increasing levels of environmental stress, namely increased temperatures. Climate change is resulting in even warmer ocean temperatures that threaten associations between Symbiodinium and their hosts. In this project the investigators examine the genetic diversity of Symbiodinium and the potential for this important species to evolve in response to temperature. The project will also address whether the ecological and evolutionary dynamics of the Symbiodinium population affect the performance of their host. If so, this suggests that the evolution of microscopic organisms with short generation times could confer adaptation to longer-lived host species on ecologically and economically vital coral reefs. Given that diversity is already being lost on many reefs, considering how evolutionary changes in Symbiodinium will affect reef species is crucial for predicting the responses of reefs to future climate change. This project provides training for two graduate students and several undergraduates at a Hispanic-serving institution. This work includes outreach to the students and the general public through the Aquarium of Niagara, local K-12 schools, and web-based education modules. The effects of evolution on contemporary ecological processes are at the forefront of research in evolutionary ecology. This project will answer the call for experiments elucidating the effects of genetic variation in Symbiodinium performance and the effect on the response of the holobiont (host and symbiont) to increased temperature. These experiments examine the effects of temperature through both ecological and evolutionary mechanisms and will determine the relative importance of adaptation and acclimatization in replicated experimental populations. The investigators will examine how genetic variation within a species (Symbiodinium antillogorgium) affects symbiont performance in culture and in the host and how this affects the response of the holobiont to increased temperature. Further, the project examines whether holobiont response to increased temperature associated with climate change depends on particular GxG host-symbiont combinations. Moreover, the investigators will examine the effects of symbiont history on mutualist hosts, which have been largely ignored in eco-evolutionary studies. These experiments provide a first step in predicting whether invertebrate hosts on coral reefs will respond to global change via adaptation of their symbionts.