How do animals cope with stress in different environments? (Ref 4595)

动物在不同环境下如何应对压力？

• 批准号: 2859397
• 金额: --
• 依托单位: UNIVERSITY OF EXETER
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2859397
• 关键词: How; do; animals; cope; stress

Project BackgroundWe know that all organisms have a stress response system to cope with environmental challenges, yet its precise form varies hugely within and between individuals. At its heart, a stress response system should be able to throw everything at responding to a stressor (fighting, fleeing), but at the same time it should minimise disruption to the animal's other physiological systems. Recently, we have identified that stressor predictability is likely to be a major driver of variation in stress responses. This project further examine this hypothesis. You will be trained in computer programming and modelling techniques (such as control theory) to predict what key features and limitations of stress response systems evolve across different environments. We then put these models on stressor predictability to the test by using lab experiments and field work in the Mediterranean field cricket Gryllus bimaculatus.Project Aims and MethodsBelow we suggest three potential components of this PhD project to study the evolution of stress responses in animals. Of course, we encourage you to think about different components that are closer to your interests, as we believe that PhD students should lead the design of their projects. 1. Evolutionary models of stress response systems In this part of the project you will receive training in mathematical modelling in biology, where you will learn how to use control theory to develop an evolutionary model of a stress response. You can then use these skills to analyze what features characterize stress response systems that experience fluctuations in stressor occurrence. These models then allow one to predict how key features of stress response systems (e.g., robustness, damage accumulation) vary with different environments. Moreover, they also can inform us how changes in condition (e.g., medical interventions, chronic stress) affect the stress response.2. Experimentally measure how stressor predictability affects the stress response Crickets are a great model organism to the study of stress responses as the underlying stress response pathways are starting to be discovered and its genome has recently been sequenced. We will expose crickets to signals that indicate predation (e.g., scent of predators like the common toad). Stress responses are measured through hormones such as octopamine, which is a key component of the insect stress hormone pathway. Existing models made by us show that predictable vs random occurrences of stressors should affect the magnitude of the stress response. In this part of the project we aim to test this prediction by comparing different treatment groups that vary in the predictability of stressor occurrence vs absence during development.3. Field work on naturally occurring stressors in cricket populations in Portugal We aim to compare stress responses in field populations of Gryllus bimaculatus across Portugal, which differ in composition and density of predators. Moreover, we can also experimentally manipulate stressor occurrence by using protective cages that keep out key predators such as snakes, toads and mice.

我们知道所有生物都有应激反应系统来应对环境挑战，但其具体形式在个体内部和个体之间差异很大。从本质上讲，应激反应系统应该能够对应激源（战斗、逃跑）做出反应，但同时，它应该尽量减少对动物其他生理系统的干扰。最近，我们发现压力源的可预测性可能是压力反应变化的主要驱动因素。本项目进一步检验了这一假设。您将接受计算机编程和建模技术（如控制理论）方面的培训，以预测应力反应系统在不同环境中演变的关键特征和局限性。然后，我们通过实验室实验和地中海野蟋蟀Gryllus bimaculatus的实地工作，将这些模型用于压力源可预测性的测试。项目目标和方法下面我们建议这个博士项目的三个潜在组成部分来研究动物应激反应的进化。当然，我们鼓励您考虑与您的兴趣更接近的不同组件，因为我们认为博士生应该领导他们的项目设计。1. 在项目的这一部分，你将接受生物学数学建模的培训，在那里你将学习如何使用控制理论来建立压力反应的进化模型。然后，您可以使用这些技能来分析在压力源发生时经历波动的压力反应系统的特征。然后，这些模型允许人们预测应力响应系统的关键特征（例如，鲁棒性，损伤积累）如何随不同环境而变化。此外，它们还可以告诉我们环境的变化（例如，医疗干预，慢性压力）是如何影响压力反应的。随着潜在的应激反应途径开始被发现，其基因组最近被测序，蟋蟀是研究应激反应的一个很好的模式生物。我们将蟋蟀暴露在捕食者的信号中（例如，像普通蟾蜍这样的捕食者的气味）。应激反应是通过诸如章鱼胺之类的激素来测量的，章鱼胺是昆虫应激激素途径的关键组成部分。我们现有的模型表明，可预测的和随机发生的压力源应该影响压力反应的大小。在项目的这一部分中，我们的目标是通过比较不同的治疗组来测试这一预测，这些治疗组在发展过程中对压力源的发生和缺失的可预测性有所不同。在葡萄牙蟋蟀种群自然发生的压力源的实地工作我们的目的是比较在葡萄牙的Gryllus biaculatus野外种群的应激反应，不同的组成和捕食者的密度。此外，我们还可以通过实验控制压力源的发生，方法是使用保护笼，将蛇、蟾蜍和老鼠等主要捕食者拒之门外。