Department of Biology, Hofstra University, Hempstead, NY 11549, U.S.A.
Department of Biological Sciences, Fordham University, Bronx, NY 10458, U.S.A.
Biol Rev Camb Philos Soc. 2018 Feb;93(1):98-114. doi: 10.1111/brv.12334. Epub 2017 Apr 26.
Fear of predation is a universal motivator. Because predators hunt using stealth and surprise, there is a widespread ability among prey to assess risk from chemical information - scents - in their environment. Consequently, scents often act as particularly strong modulators of memory and emotions. Recent advances in ecological research and analytical technology are leading to novel ways to use this chemical information to create effective attractants, repellents and anti-anxiolytic compounds for wildlife managers, conservation biologists and health practitioners. However, there is extensive variation in the design, results, and interpretation of studies of olfactory-based risk discrimination. To understand the highly variable literature in this area, we adopt a multi-disciplinary approach and synthesize the latest findings from neurobiology, chemical ecology, and ethology to propose a contemporary framework that accounts for such disparate factors as the time-limited stability of chemicals, highly canalized mechanisms that influence prey responses, and the context within which these scents are detected (e.g. availability of alternative resources, perceived shelter, and ambient physical parameters). This framework helps to account for the wide range of reported responses by prey to predator scents, and explains, paradoxically, how the same individual predator scent can be interpreted as either safe or dangerous to a prey animal depending on how, when and where the cue was deposited. We provide a hypothetical example to illustrate the most common factors that influence how a predator scent (from dingoes, Canis dingo) may both attract and repel the same target organism (kangaroos, Macropus spp.). This framework identifies the catalysts that enable dynamic scents, odours or odorants to be used as attractants as well as deterrents. Because effective scent tools often relate to traumatic memories (fear and/or anxiety) that cause future avoidance, this information may also guide the development of appeasement, enrichment and anti-anxiolytic compounds, and help explain the observed variation in post-traumatic-related behaviours (including post-traumatic stress disorder, PTSD) among diverse terrestrial taxa, including humans.
恐惧是一种普遍的动机。由于捕食者使用隐身和突袭来捕猎，因此猎物有一种广泛的能力，可以通过环境中的化学信息（气味）来评估风险。因此，气味通常是记忆和情绪的特别强烈的调节剂。生态研究和分析技术的最新进展正在为野生动物管理者、保护生物学家和健康从业者创造有效的吸引剂、驱避剂和抗焦虑化合物提供新方法。然而，基于嗅觉的风险辨别研究在设计、结果和解释方面存在广泛的差异。为了理解该领域高度可变的文献，我们采用多学科方法，综合神经生物学、化学生态学和行为学的最新发现，提出了一个当代框架，该框架考虑了化学物质的限时稳定性、影响猎物反应的高度渠道化机制以及这些气味被检测到的背景（例如，替代资源的可用性、感知庇护所和环境物理参数）等因素。该框架有助于解释猎物对捕食者气味的广泛反应，并解释了为什么相同的个体捕食者气味可以被解释为对猎物动物安全或危险，具体取决于线索的放置方式、时间和地点。我们提供了一个假设的例子来说明影响猎物对捕食者气味（来自野狗，Canis dingo）的反应的最常见因素，并解释了为什么相同的捕食者气味可以同时吸引和排斥同一目标生物（袋鼠，Macropus spp.）。该框架确定了使动态气味、气味或气味剂可用作吸引剂和驱避剂的催化剂。因为有效的气味工具通常与引起未来回避的创伤记忆（恐惧和/或焦虑）有关，所以这些信息也可能指导安抚、丰富和抗焦虑化合物的开发，并有助于解释不同陆地生物类群（包括人类）中与创伤后相关行为的观察到的变化（包括创伤后应激障碍，PTSD）。
