Downie Adam T, Champion Curtis, Booth David J
School of Mathematical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia.
Fisheries Research, Department of Primary Industries and Regional Development, National Marine Science Center, Coffs Harbor, New South Wales, Australia.
Glob Chang Biol. 2025 Apr;31(4):e70213. doi: 10.1111/gcb.70213.
Tropicalization, the phenomena by which tropical organisms are extending their distributions poleward into temperate latitudes in response to increasing temperatures and strengthening boundary currents, is occurring globally. Vagrant tropical species have large ecological and economic ramifications for the temperate habitats they invade. However, not all vagrants are able to persist long term in temperate habitats, with the first winter being a potential bottleneck for their persistence. This brings into question how some tropical vagrant species are successful at surviving temperate conditions and the physiology underpinning this success. This provides the opportunity to not only look at the available data introspectively but also forward-thinking by applying a range of holistic physiological traits relevant for biology and management. Therefore, the aim of our review is twofold: to review the current state-of-knowledge of the physiological mechanisms underpinning tropicalization and to develop a physiological framework by which current practices can complement new perspectives and tools. We use range-expanding tropical reef fishes as a model group of over 100 species undergoing climate-driven range shifts and eastern Australia as a case-study location due to it being a primary focal "living laboratory" for understanding tropicalization dynamics since the early 2000s. Current studies suggest that diet, behavior, and metabolic trade-offs may explain vagrant fish persistence, but these studies focus on whole-animal traits. Our framework helps expand upon focal traits, life stages, experimental design, physiological traits (e.g., we highlight the value of genetic and cellular markers for metabolic pathway changes under cold stress as potential biomarkers) and species to improve our understanding of the mechanisms underpinning tropicalization. Taken together, our framework places emphasis on measuring a suite of complimentary physiological traits, from cellular to whole-animal, to help guide future predictions of the long-term persistence of tropical species in temperate habitats.
热带化现象是指热带生物因气温升高和边界流增强而将其分布范围向极地扩展至温带地区，这一现象正在全球范围内发生。漂泊的热带物种对它们所入侵的温带栖息地具有重大的生态和经济影响。然而，并非所有漂泊物种都能在温带栖息地长期生存，第一个冬天可能是它们生存的潜在瓶颈。这就引发了一个问题，即一些热带漂泊物种是如何成功在温带条件下生存的，以及支撑这种成功的生理机制是什么。这不仅提供了一个机会来内省现有数据，还能通过应用一系列与生物学和管理相关的整体生理特征进行前瞻性思考。因此，我们综述的目的有两个：回顾支撑热带化的生理机制的当前知识状态，并建立一个生理框架，使当前的实践能够补充新的观点和工具。我们将正在进行气候驱动范围转移的100多种热带珊瑚礁鱼类作为模型组，并以澳大利亚东部作为案例研究地点，因为自21世纪初以来，这里一直是理解热带化动态的主要重点“活体实验室”。目前的研究表明，饮食、行为和代谢权衡可能解释漂泊鱼类的生存情况，但这些研究侧重于动物整体特征。我们的框架有助于扩展重点特征、生命阶段、实验设计、生理特征（例如，我们强调遗传和细胞标记物在冷应激下代谢途径变化作为潜在生物标志物的价值）和物种，以增进我们对支撑热带化机制的理解。综上所述，我们的框架强调测量一系列从细胞到动物整体的互补生理特征，以帮助指导未来对热带物种在温带栖息地长期生存的预测。
