Is countershading camouflage robust to lighting change due to weather?
Is countershading camouflage robust to lighting change due to weather?
复制标题
DOI：
10.1098/rsos.170801
复制
发表时间：
2018-03
影响因子：
3.5
通讯作者：
Harris JM
中科院分区：
文献类型：
--
作者：
Penacchio O;Lovell PG;Harris JM
反遮阳是一种颜色模式，被认为是为了实现伪装而进化的。通过采用一种颜色模式，使面向太阳的表面更暗，背向太阳的表面更亮，从动物身上反射的光的总量可以变得更均匀明亮。因此，反阴影可以通过增加背景匹配或减少形状线索来促进视觉伪装。然而，反遮光的有用性受到特定模式的限制，只有在非常特定的照明条件下才能提供“最佳”伪装。在这项研究中，我们测试了反遮阳伪装对天气引起的光照变化的鲁棒性，将人类参与者作为“一般”捕食者。在模拟的三维环境中，我们构建了一系列简单的叶子形状的物品和一个椭球形的目标“猎物”。我们将这些物品设置在两个光线环境中：强烈定向的“阳光”和更分散的“阴天”。目标物体被给予这两种环境类型之一的最佳反遮光图案或显示统一的图案。通过测量检测时间和精度，探讨目标检测是否以及如何依赖于目标物体上的颜色模式与场景照明的匹配。当反遮挡与光照相适应时，检测时间最长；不正确伪装的目标被发现的速度和准确性与统一颜色的目标相似。我们的结论是，光环境中的结构变化，例如由天气差异引起的变化，确实会改变反遮光伪装的有效性。
Countershading is a pattern of coloration thought to have evolved in order to implement camouflage. By adopting a pattern of coloration that makes the surface facing towards the sun darker and the surface facing away from the sun lighter, the overall amount of light reflected off an animal can be made more uniformly bright. Countershading could hence contribute to visual camouflage by increasing background matching or reducing cues to shape. However, the usefulness of countershading is constrained by a particular pattern delivering ‘optimal’ camouflage only for very specific lighting conditions. In this study, we test the robustness of countershading camouflage to lighting change due to weather, using human participants as a ‘generic’ predator. In a simulated three-dimensional environment, we constructed an array of simple leaf-shaped items and a single ellipsoidal target ‘prey’. We set these items in two light environments: strongly directional ‘sunny’ and more diffuse ‘cloudy’. The target object was given the optimal pattern of countershading for one of these two environment types or displayed a uniform pattern. By measuring detection time and accuracy, we explored whether and how target detection depended on the match between the pattern of coloration on the target object and scene lighting. Detection times were longest when the countershading was appropriate to the illumination; incorrectly camouflaged targets were detected with a similar pattern of speed and accuracy to uniformly coloured targets. We conclude that structural changes in light environment, such as caused by differences in weather, do change the effectiveness of countershading camouflage.
登录
查看更多内容
DOI：
10.1098/rstb.2008.0221
发表时间：
2009-02-27
影响因子：
6.3
作者：
Caro, Tim
通讯作者：
Caro, Tim
影响因子：
1.9
作者：
Caro, Tim;Beeman, Karrie;Whitehead, Hal
通讯作者：
Whitehead, Hal
影响因子：
4.6
作者：
Penacchio O;Harris JM;Lovell PG
通讯作者：
Lovell PG
影响因子：
5.2
作者：
Penacchio O;Cuthill IC;Lovell PG;Ruxton GD;Harris JM
通讯作者：
Harris JM
影响因子：
1.4
作者：
Qadri, Muhammad A. J.;Romero, L. Michael;Cook, Robert G.
通讯作者：
Cook, Robert G.