Collaborative Research: Friendly competition - infusing ecology and evolution at the frontiers of the dilution effect in disease ecology

野生种群的疾病暴发继续增加，了解这种增加已成为一项重大的环境挑战。一种流行的解释是，生物多样性的丧失，尤其是抗病物种的丧失，助长了疾病的流行。因此，加强和保护物种多样性可能会减少疾病和对宿主种群的相关负面影响。本项目将新的数学模型与实验相结合，在食物网/群落背景下挑战这一解释，使用水蚤（一种水生无脊椎动物）和真菌病原体，探索多种病原体宿主的稀释效应如何在生态（种间竞争）和进化动态中发挥作用。PI提出，在这种情况下，决定传播的关键特征也会影响与其他社区成员、剥削性竞争对手及其共同猎物的相互作用，这可能会改变宿主-病原体动力学的细节，特别是稀释效应。模型和实验将共同确定宿主之间的竞争是否也会影响疾病的传播，宿主竞争的食物的营养价值是否会影响对疾病的易感性，以及宿主对疾病的快速适应是否可以抵消生物多样性的丧失，从而可能减少疾病的爆发。一个跨学科的研究小组将利用被一种致命病原体感染的常见淡水生物来解决这些问题。水蚤-真菌系统是提出优雅的理论问题的理想选择，而提出的雄心勃勃的实验将产生检验理论的经验数据。这个多学科的项目将为疾病控制提供新的见解。该项目还将增加学生和博士后研究人员的培训机会，特别关注代表性不足的群体成员和从事数学和生物学工作的本科生。此外，调查人员还将通过非政府组织、高中、儿童博物馆和一个面向女中学生的项目开展工作，传播研究成果，并通过实践项目培训未来的科学家。

Outbreaks of disease continue to increase in wild populations, and understanding this increase has become a major environmental challenge. A popular explanation is that loss of biodiversity, and particularly of species that are resistant to disease, encourages disease epidemics. Thus, enhancement and preservation of species diversity might reduce disease and associated negative effects on host populations. This project combines new mathematical models with experiments to challenge this explanation in a food web/community context, using Daphnia (an aquatic invertebrate) and a fungal pathogen, to explore how the dilution effect of multiple pathogen hosts plays itself out in the face of ecological (interspecific competition) and evolutionary dynamics. The PI's propose that key traits determining transmission also affect interactions with other community members, exploitative competitors and their shared prey in this case, which may alter the details of host-pathogen dynamics, particularly the dilution effect. Models and experiments together will determine whether competition among hosts also influences the spread of disease, whether nutritional value of the food for which hosts compete influences susceptibility to disease, and whether rapid adaptation of hosts to disease can counteract the loss of biodiversity, potentially reducing disease outbreaks. An interdisciplinary team of researchers will tackle these issues using common freshwater organisms that are infected by a virulent pathogen. The Daphnia-fungus system is ideal for asking elegant theoretical questions, and the proposed ambitious experiments will generate empirical data to test the theory.This multi-disciplinary project will produce new insights into a provocative option for disease control. This project will also enhance training opportunities for students and postdoctoral researchers, with particular focus on members of underrepresented groups and undergraduates working with mathematics and biology. Additionally, the investigators will work through non-governmental organizations, high schools, a children's museum, and a program for middle school girls to disseminate results and train future scientists with hands-on projects.