Data from: Stomatopods detect and assess achromatic cues in contests

Conspicuous, colorful displays are often used by animals to communicate within and between species. Previously, researchers have manipulated specific components of color signals (i.e., hue, total reflectance, and/or chroma) using paints, photographs, videos, or filters. However, these manipulations may not adequately mimic the spectrum of color signals outside the range of human perception. Thus, these methods are inappropriate for organisms with unconventional visual systems, such as stomatopods (mantis shrimp). Here, we describe a novel application of a femtosecond laser to increase total reflectance of the stomatopod meral spot, a distinct area on the raptorial appendage used in territorial contests. Ultrafast lasers provide a programmable way to precisely manipulate patch total reflectance of live stomatopods without causing collateral damage. We tested how experimentally increasing meral spot reflectance impacted receiver behavior during territorial contests. Contests in which receiver stomatopods faced an opponent with a lightened meral spot were shorter and receivers showed increased rates of agonistic behaviors. This result suggests that lighter meral spots indicate lower fighting ability; thus, receivers are more willing to engage in a contest. This research provides the first demonstration that stomatopods can detect and assess achromatic variation in contests. Furthermore, we demonstrate that ultrafast lasers provide a powerful tool to investigate achromatic signaling, particularly for organisms whose size, aquatic habitat, or visual system otherwise prevent realistic alterations to color signals (e.g., butterflies, jumping spiders, or decapod crustaceans). This study advances our knowledge about stomatopod visual communication and offers a valuable tool for future research.

醒目的色彩展示常被动物用于种内与种间的信息传递。此前，研究者多通过颜料、照片、视频或滤光片等手段操控色彩信号的特定参数，即色调（hue）、总反射率（total reflectance）以及彩度（chroma）。然而此类操控手段无法充分模拟超出人类感知范围的色彩信号光谱，因此并不适用于拥有非常规视觉系统的生物，例如口足类（stomatopods，螳螂虾）。本研究首次将飞秒激光（femtosecond laser）应用于提升口足类螯斑的总反射率——该斑点是其掠食附肢上用于领地争夺的标志性区域。超短脉冲激光可通过可编程的方式精准操控活体口足类的螯斑总反射率，且不会造成附带损伤。我们测试了实验性提升螯斑反射率对领地争夺中接收方行为的影响。当接收方口足类面对螯斑被提亮的对手时，领地争夺的时长更短，且接收方展现出更高频率的争斗行为。该结果表明，更明亮的螯斑代表更低的战斗能力，因此接收方更愿意参与争斗。本研究首次证实，口足类能够在领地争夺中感知并评估消色差信号差异。此外，本研究证明超短脉冲激光是研究消色差信号交流的有力工具，尤其适用于那些因体型、水生栖息环境或视觉系统限制，难以对色彩信号进行真实操控的生物，例如蝴蝶、跳蛛或十足目甲壳动物（decapod crustaceans）。本研究深化了我们对口足类视觉交流的认知，并为未来相关研究提供了极具价值的实验工具。