School of Biological Sciences, University of Bristol, Bristol Life Sciences Building, Bristol, UK.
Department of Psychology, Northeastern University, Boston, MA, USA.
Commun Biol. 2024 Oct 3;7(1):1255. doi: 10.1038/s42003-024-06953-5.
Motion vision is vital for a wide range of animal behaviors. Fiddler crabs, for example, rely heavily on motion to detect the movement of avian predators. They are known to detect first-order motion using both intensity (defined by spatiotemporal correlations in luminance) and polarization information (defined separately as spatiotemporal correlations in the degree and/or angle of polarization). However, little is known about their ability to detect second-order motion, another important form of motion information; defined separately by spatiotemporal correlations in higher-order image properties. In this work we used behavioral experiments to test how fiddler crabs (Afruca tangeri) responded to both second-order intensity and polarization stimuli. Fiddler crabs responded to a number of different intensity based second-order stimuli. Furthermore, the crabs also responded to second-order polarization stimuli, a behaviorally relevant stimulus applicable to an unpolarized flying bird when viewed against a polarized sky. The detection of second-order motion in polarization is, to the best of our knowledge, the first demonstration of this ability in any animal. This discovery therefore opens a new dimension in our understanding of how animals use polarization vision for target detection and the broader importance of second-order motion detection for animal behavior.
运动视觉对于广泛的动物行为至关重要。例如，招潮蟹 heavily 依赖运动来 detect 鸟类捕食者的运动。已知它们既可以使用强度（由亮度的时空相关性定义），也可以使用偏振信息（分别由偏振度和/或角度的时空相关性定义）来 detect 一阶运动。然而，对于它们 detect 二阶运动的能力知之甚少，二阶运动是另一种重要的运动信息形式，由高阶图像属性的时空相关性定义。在这项工作中，我们使用行为实验来测试招潮蟹（Afruca tangeri）对二阶强度和偏振刺激的反应。招潮蟹对许多不同的基于强度的二阶刺激做出了反应。此外，这些螃蟹也对二阶偏振刺激做出了反应，这是一种行为相关的刺激，当从偏振天空中观察到非偏振飞行的鸟类时，这种刺激是适用的。据我们所知，偏振中二阶运动的 detect 是在任何动物中首次展示这种能力。因此，这一发现为我们理解动物如何利用偏振视觉来 detect 目标提供了新的维度，也为二阶运动 detect 对动物行为的更广泛重要性提供了新的维度。
