ICBAS-Institute of Biomedical Sciences Abel Salazar, University of Porto, Porto, Portugal.
Proc Biol Sci. 2012 Jan 7;279(1726):84-90. doi: 10.1098/rspb.2011.0196. Epub 2011 May 11.
To achieve effective visual camouflage, prey organisms must combine cryptic coloration with the appropriate posture and behaviour to render them difficult to be detected or recognized. Body patterning has been studied in various taxa, yet body postures and their implementation on different backgrounds have seldom been studied experimentally. Here, we provide the first experimental evidence that cuttlefish (Sepia officinalis), masters of rapid adaptive camouflage, use visual cues from adjacent visual stimuli to control arm postures. Cuttlefish were presented with a square wave stimulus (period = 0.47 cm; black and white stripes) that was angled 0°, 45° or 90° relative to the animals' horizontal body axis. Cuttlefish positioned their arms parallel, obliquely or transversely to their body axis according to the orientation of the stripes. These experimental results corroborate our field observations of cuttlefish camouflage behaviour in which flexible, precise arm posture is often tailored to match nearby objects. By relating the cuttlefishes' visual perception of backgrounds to their versatile postural behaviour, our results highlight yet another of the many flexible and adaptive anti-predator tactics adopted by cephalopods.
为了实现有效的视觉伪装，猎物生物必须将隐藏的颜色与适当的姿势和行为相结合，使它们难以被发现或识别。身体图案在各种分类群中都有研究，但身体姿势及其在不同背景下的实施很少进行实验研究。在这里，我们提供了第一个实验证据，证明墨鱼（Sepia officinalis），快速自适应伪装的大师，使用来自相邻视觉刺激的视觉线索来控制手臂姿势。墨鱼被呈现出一个方波刺激（周期= 0.47 厘米；黑白条纹），相对于动物的水平身体轴，该刺激的角度为 0°、45°或 90°。墨鱼根据条纹的方向将手臂平行、倾斜或横向放置在身体轴上。这些实验结果证实了我们在野外观察到的墨鱼伪装行为，即灵活、精确的手臂姿势通常根据附近物体进行调整。通过将墨鱼对背景的视觉感知与其多功能的姿势行为联系起来，我们的结果突出了头足类动物采用的许多灵活和适应性的另一种抗捕食策略。
