Active photolocation: A new frontier in active sensing

主动感觉系统依赖于自我产生的能量来收集有关环境的信息，已经在几种动物身上得到了很好的研究。例如，蝙蝠发出尖锐的声音，并通过反射来定位猎物，避开障碍物，并与同种动物交流。主要的主动感觉方式，回声定位和电定位，已经受到了广泛的关注，并产生了大量有影响力的发现。然而，主动光定位，即通过光发射或重定向感知环境的过程，实际上尚未得到研究。这是令人惊讶的，因为许多深海鱼类和一些夜间活动的珊瑚礁鱼类在眼睛附近都有发光器官。这些“手电筒”被假设用于猎物/捕食者探测，引诱猎物，以及种内交流，如群体凝聚力和个体识别。然而，这些光器官的功能大多是推测性的；只有一项研究量化了闪光鱼的光团使用情况。此外，我和我的一组同事最近的研究表明，许多昼行鱼的虹膜上有一种结构，可以改变或改变环境光的质量，从而提高它们发现潜在猎物和捕食者的可能性。白天活跃的光定位可能在鱼类中很普遍，我们小组的工作为研究这种行为以及相关的生态和进化后果奠定了基础。凭借我的第一笔发现基金，我将启动一项全面的研究计划，旨在了解主动光定位的机制和功能。在前五年，我将建立一个长期的实验项目，1)夜间主动光定位，以闪光鱼为模型，2)白天主动光定位，以三棘棘鱼为模型。我的研究将为测试限制主动光定位进化的权衡提供一个新的框架，但也会对我们对鱼眼在物种之间的共同进化的理解产生影响。主动光定位在主动传感文献中被严重忽视，因此为新发现提供了令人兴奋的机会。这项研究计划在加拿大是独一无二的，因此对主动传感的国际研究做出了独特的加拿大贡献。我的研究项目将为下一代科学家提供多学科的培训环境。我的学生将通过畜牧和护理、科学水肺潜水和其他实地工作获得广泛的可转移技能，并接受包括光谱辐射测量、多光谱成像和高级视觉建模在内的最先进技术的培训。所有研究成果将通过出版预印本或开放获取文章的方式与科学界和公众进行交流。

Active sensory systems, which rely on self-generated energy to gather information about the environment, have been well studied in several animals. For example, bats emit high-pitched sounds and detect their reflection to locate prey items, avoid obstacles, and communicate with conspecifics. The main active sensory modalities, echolocation and electrolocation, have received much attention, and generated a tremendous amount of influential findings. However, active photolocation, the process of sensing the environment through light emission or redirection, is virtually unstudied. This is surprising since a large number of deep-sea fish species, and several nocturnal reef fish species possess light producing organs near their eyes. These `flashlights' are hypothetically used for prey/predator detection, luring prey, and intraspecific communication such as group cohesion and individual recognition. However, the proposed functions of these light organs are mostly speculative; only a single study has quantified photophore use in flashlight fishes. Furthermore, recent studies, by a group of colleagues and myself, demonstrated that many diurnal fish possess structures on their irises that redirect or change the quality of ambient light, allowing them to increase their probability of detecting potential prey and predators. Diurnal active photolocation could be widespread in fish, and work from our group has laid the foundation for studying this behaviour and associated ecological and evolutionary consequences. With my first Discovery Grant I will initiate a comprehensive research programme aimed at understanding the mechanisms and functions of active photolocation. In the first five years, I will establish a long-term experimental program on 1) nocturnal active photolocation using the flashlight fish Anomalops katoptron as a model, and 2) diurnal active photolocation using the three-spined stickleback Gasterosteus aculeatus. My studies will provide a novel framework for testing trade-offs constraining the evolution of active photolocation, but also have ramifications on our understanding of the co-evolution of fish eyes among species. Active photolocation is heavily neglected in the active sensing literature, consequently offering exciting opportunities for novel discoveries. This research program will be unique in Canada and therefore make a distinctive Canadian contribution to the international study of active sensing. My research program will provide a multidisciplinary training environment for the next generation of scientist. My students will gain broadly transferable skills through e.g., animal husbandry and care, scientific SCUBA diving and other field work, and train with state of the art techniques including spectroradiometry, multispectral imaging, and advanced visual modelling. All research results will be communicated to the scientific community and the general public through the publishing of pre-print or open-access articles.