Fungus, frogs and MHC: the role of sexual selection in the evolution of disease resistance

性选择是一种强大的进化力量，可以促进或抑制对环境挑战的适应。当种群面临新的病原体时，SS可以通过影响抗性等位基因的传播来影响它们的持久性；具体地说，主要组织相容性复合体(MHC)编码识别病原体并激活获得性免疫系统的蛋白质。许多脊椎动物优先与携带有益的MHC等位基因的伴侣交配，从而对后代产生更高的抵抗力。在这里，我建议研究SS在两栖动物对壶菌病(Chytrid)抗药性(Chytrid)的进化动力学中的作用。chytrid是一种新出现的传染病，正在导致全球种群的减少和灭绝。我将使用毒蛙，这是一个物种丰富的群体，SS的强度在不同物种之间存在差异，并且正在经历种群数量的急剧下降。我将测试配偶的选择是否受i)MHC和ii)双方感染状况的影响。随后，我将采用比较分析和实地调查的方法来评估SS的强度与物种对菊苣的易感性之间的关系，检验SS选择的物种更具抗性的预测。本项目不仅有助于我们对SS在适应和疾病动态中的作用的一般理解，而且还将首次对两栖动物基于MHC的配偶选择进行实验分析。结果将与两栖动物保护高度相关，因为它确定了导致种类差异的主要因素，这将有助于确定保护优先事项。在我的整个学术生涯中，我一直在与chytrid合作；这个项目让我能够专注于主人，它一直是较少研究的目标，迫切需要保护。该项目将在格罗宁根大学进行，由SS和毒蛙专家Maan博士监督；实地工作将在巴西进行。

Sexual selection (SS) is a strong evolutionary force that can promote or inhibit adaptation to environmental challenges. When populations face novel pathogens, SS can influence their persistence by impacting the spread of resistance alleles; specifically, the Major Histocompatibility Complex (MHC) that encodes proteins that recognize pathogens and activate the acquired immune system. Many vertebrates preferentially mate with partners carrying beneficial MHC alleles, conferring higher resistance to the offspring. Here, I propose to study the role of SS in the evolutionary dynamics of amphibian resistance to chytridiomycosis (chytrid), an emerging infectious disease that is causing population declines and extinctions worldwide. I will use poison frogs, a species-rich group in which the strength of SS differs between species, and that is experiencing dramatic population declines. I will test whether mate choice is influenced by i) MHC and ii) infection status ofboth partners. Subsequently, I will use comparative analysis and field surveys to iii) evaluate the association between the strength of SS and species’ susceptibility to chytrid, testing the prediction that species with SS selection are more resistant.This project will not only contribute to our general understanding of the role of SS in adaptation and disease dynamics, but also present the first experimental analysis of MHC-based mate choice in amphibians. Results will be highly relevant for amphibian conservation, by identifying a major factor underlying species differences in chytrid resistance, which will help to set conservation priorities. I have worked with chytrid throughout my academic career; this project allows me to focus on the host, which has been the target of fewer studies and is in dire need of conservation. The project will be conducted at the University of Groningen under the supervision of Dr. Maan, an expert on SS and poison frogs; field work will be carried out in Brazil.