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，特别是对疾病具有抵抗力的物种的丧失，助长了疾病流行。因此，加强和保护物种多样性可能会减少疾病和相关的对宿主种群的负面影响。该项目将新的数学模型与实验相结合，利用水生无脊椎动物Daphnia(一种水生无脊椎动物)和一种真菌病原体，在食物网/群落的背景下挑战这一解释，以探索面对生态(种间竞争)和进化动力学，多个病原体宿主的稀释效应是如何发挥作用的。PI提出，在这种情况下，决定传播的关键性状也会影响与其他群落成员、剥削性竞争对手和他们共享的猎物的相互作用，这可能会改变宿主-病原体动态的细节，特别是稀释效应。模型和实验将共同决定宿主之间的竞争是否也影响疾病的传播，宿主竞争的食物的营养价值是否影响疾病的易感性，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，从而潜在地减少疾病爆发。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体来解决这些问题。水蚤-真菌系统是提出优雅的理论问题的理想选择，拟议中雄心勃勃的实验将产生验证理论的经验数据。这个多学科项目将产生对疾病控制的挑衅性选择的新见解。该项目还将增加学生和博士后研究人员的培训机会，特别侧重于任职人数不足的群体成员和从事数学和生物工作的本科生。此外，研究人员将通过非政府组织、高中、儿童博物馆和一个针对中学女孩的项目来传播结果，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.