Centre for Ecology and Conservation, University of Exeter (Penryn Campus), Penryn, Cornwall TR10 9FE, UK; Department of Biology, Umm Al-Qura University, Makkah, Saudi Arabia.
Centre for Ecology and Conservation, University of Exeter (Penryn Campus), Penryn, Cornwall TR10 9FE, UK.
Curr Biol. 2024 Aug 5;34(15):R722-R723. doi: 10.1016/j.cub.2024.06.039.
Camouflage is vital for the survival of many prey species, including ground-nesting birds. Egg camouflage via background matching and disruptive coloration (high contrast markings that break up the body outline) is often behaviourally mediated by selecting substrates that enhance egg camouflage. However, the mechanisms controlling this behaviour in birds have remained unknown. Several, not mutually exclusive, mechanisms have been suggested to control background choice for egg camouflage. These include where individual background preferences are genetically linked to egg coloration, enabled through learning egg appearances from previous breeding attempts, or modified by imprinting on visual backgrounds during early life, Here, using predator vision models, we compared the camouflage of Japanese quail (Coturnix japonica) eggs among females who were allowed to choose one of four coloured substrates on which to lay. Birds were divided into experienced females who had been given the opportunity to observe the appearance of their eggs, versus naïve females breeding for the first time. Our experiment revealed that breeding experience leads to improved background choices made for egg background matching. However, substrate choice for disruptive coloration appeared genetically determined, as both bird groups chose backgrounds that enhanced egg disruptiveness regardless of experience. These mechanisms underpin behaviours that are likely essential for birds and other animals to optimise camouflage and avoid predation.
伪装对于许多猎物物种的生存至关重要，包括地面筑巢的鸟类。通过背景匹配和破坏色（高对比度标记，打破身体轮廓）进行的卵伪装通常是通过选择增强卵伪装的基质来进行行为介导的。然而，鸟类控制这种行为的机制仍然未知。已经提出了几种并非相互排斥的机制来控制卵伪装的背景选择。这些机制包括个体对背景的偏好是否与卵的颜色在遗传上相关联，是否通过从以前的繁殖尝试中学习卵的外观来实现，或者是否通过在早期生活中对视觉背景进行印记来进行修饰。在这里，我们使用捕食者视觉模型比较了允许在四种不同颜色的基质上产卵的日本鹌鹑（Coturnix japonica）卵的伪装。将鸟类分为有经验的雌性和初次繁殖的雌性。我们的实验表明，繁殖经验会导致对卵背景匹配的背景选择得到改善。然而，破坏色的基质选择似乎是由遗传决定的，因为两组鸟类都选择了增强卵破坏度的背景，而不论其经验如何。这些机制为鸟类和其他动物优化伪装和避免捕食提供了行为基础，这些行为可能至关重要。
