Cuttlefish see shape from shading, fine-tuning coloration in response to pictorial depth cues and directional illumination.
Cuttlefish see shape from shading, fine-tuning coloration in response to pictorial depth cues and directional illumination.
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墨鱼通过阴影看到形状，根据图片深度线索和定向照明微调色彩。
DOI：
10.1098/rspb.2016.0062
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发表时间：
2016
期刊：
影响因子：
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通讯作者：
Zylinski S
中科院分区：
文献类型：
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作者：
Zylinski S
人类通过将关于光线强度的低级信息与关于物体和环境的高级知识相结合，使用阴影作为三维形式的线索。在这里，我们研究乌贼如何对光和阴影做出反应，以遮蔽其身体模式中的白色正方形(WS)特征。乌贼在鹅卵石状物体存在的情况下显示WS，它们可以对其进行着色，以向人类观察者呈现表面曲率的外观，这可能有助于伪装。在这里，我们测试他们如何在包含二维圆形刺激的视觉背景上给WS上色，其中一些是阴影以暗示表面曲率，而另一些则是均匀着色或分为暗和亮半圆。通过侧向不对称性测量，当动物休息在阴影圆形和三维半球的背景上时，WS阴影最大，而在普通白色圆圈或黑/白色半圆形上休息时，WS阴影最小。此外，当光线从着色刺激的较亮的一侧投射时，着色会得到增强，正如真实凸面所预期的那样。因此，乌贼的行为就像它从明暗处理中感知曲面曲率一样，并考虑了照明的方向。然而，WS着色的方向对背景着色和照明的方向不敏感；相反，乌贼倾向于转向面对光源。
Humans use shading as a cue to three-dimensional form by combining low-level information about light intensity with high-level knowledge about objects and the environment. Here, we examine how cuttlefishSepia officinalisrespond to light and shadow to shade the white square (WS) feature in their body pattern. Cuttlefish display the WS in the presence of pebble-like objects, and they can shade it to render the appearance of surface curvature to a human observer, which might benefit camouflage. Here we test how they colour the WS on visual backgrounds containing two-dimensional circular stimuli, some of which were shaded to suggest surface curvature, whereas others were uniformly coloured or divided into dark and light semicircles. WS shading, measured by lateral asymmetry, was greatest when the animal rested on a background of shaded circles and three-dimensional hemispheres, and less on plain white circles or black/white semicircles. In addition, shading was enhanced when light fell from the lighter side of the shaded stimulus, as expected for real convex surfaces. Thus, the cuttlefish acts as if it perceives surface curvature from shading, and takes account of the direction of illumination. However, the direction of WS shading is insensitive to the directions of background shading and illumination; instead the cuttlefish tend to turn to face the light source.