Effects of environmental change on the olfactory system of fish

对于水生动物来说，嗅觉是至关重要的，因为它与识别同类，选择配偶和避免捕食者等行为有关。此外，类似的原则适用于大多数水生生物如何闻到它们的环境;因此，它们嗅觉的质量或有效性的变化不仅会影响个体，还会影响种群，物种和生态系统。我们大气中二氧化碳的增加不仅导致海洋表面温度上升，而且还导致海洋酸化，因为释放到大气中的二氧化碳有四分之一被海洋吸收。我的研究项目旨在了解水生动物的感觉系统的功能，以更好地预测这些动物将如何应对环境变化。我最近展示了一种新的机制，海洋酸化对海洋鱼类的嗅觉系统和行为产生负面影响，这种机制与其他人提出的酸碱平衡变化无关。缺氧、高温和高CO2通常同时发生。它们被称为“致命的三人组”，因为它们有可能在不久的将来限制物种的分布。然而，它们对鱼类嗅觉的综合影响目前尚不清楚。此外，可塑性在允许生物体科普变化的环境方面可能特别重要。然而，迄今为止的所有研究都是在相对较短的时间内或在成鱼上进行的，关于它们的感觉系统适应这些条件的能力的信息很少。我建议用海军青鳉（Oryzias melanoma）作为一个模型系统，以解决以下3个短期目标：1）更好地了解海洋酸化损害嗅觉的机制; 2）确定多种应激源如何结合联合收割机影响鱼类的感觉系统; 3）阐明嗅觉系统的发育和跨代可塑性在长期环境应激反应中的作用。目标1-3的一般方法是在生物组织的多个水平上测试特定的假设，从分子水平到整个动物。我们将使用暴露于环境压力源，嗅觉神经记录，组织学，基因表达和行为测试的组合来解决这些目标。所要求的资金将培养3名博士，2名硕士和5名理学学士学生，他们将获得对许多科学职业非常宝贵的高级技能。这项拟议中的工作预计将为理解环境变化如何影响鱼类的感觉系统做出独特而重大的贡献。这项研究将为人类气候变化的潜在影响提供重要的见解，不仅对行为和生理，而且对他们科普这种快速变化的环境的能力。这些发现对海洋保护、渔业管理和全球粮食生产具有明显的影响。

For aquatic animals, the sense of smell is vital, as it has been linked to behaviours such as recognizing conspecifics, selecting mates and avoiding predators. Moreover, similar principles apply to how most aquatic organisms smell their environment; therefore, a change in the quality or effectiveness of their sense of smell could affect not only individuals but populations, species and ecosystems. The increase in CO2 in our atmosphere is causing not only an increase in sea surface temperatures but also ocean acidification, as a quarter of the CO2 released into the atmosphere is absorbed by the oceans. My research program aims to understand the functioning of the sensory systems of aquatic animals to better predict how these animals will respond to environmental change. I have recently shown a new mechanism by which ocean acidification negatively affects the olfactory system and behaviour of marine fish that is independent of changes in acid-base balance proposed by others. Hypoxia, high temperature, and high CO2 often occur together naturally. They are known as the "deadly trio" because they have the potential to limit species distribution in the near future. However, their combined effects on the olfaction of fish is currently not known. Moreover, plasticity is likely to be especially important in allowing organisms to cope with changing environments. Yet, all studies to date have been performed over relatively short periods or on adult fish, with little information about the capacity of their sensory systems to acclimate to these conditions. I propose to use the marine medaka (Oryzias melastigma) as a model system to address the following 3 short-term objectives: 1) Establish a better understanding of the mechanisms by which ocean acidification impairs olfaction; 2) Determine how multiple stressors combine to affect the sensory systems of fish; 3) Elucidate the role of developmental and trans-generational plasticity of the olfactory system in response to prolonged environmental stress. The general approach to objective 1-3 is to test specific hypotheses at multiple levels of biological organization, from the molecular level to the whole animal. We will use a combination of exposures to environmental stressors, olfactory nerve recording, histology, gene expression and behavioural tests to address these objectives. The funding requested will train 3 PhD, 2 MSc and 5 BSc students, who will obtain advanced skills that are invaluable for many scientific careers. The proposed work is expected to make unique and significant contributions to the understanding of how environmental change can affect the sensory systems of fish. This research will provide important insights into the potential effects of anthropogenic climate change not only on the behaviour and physiology but also their ability to cope with such a rapidly changing environment. The findings have clear implications for marine conservation, fisheries management and global food production.