Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK.
Science. 2012 Aug 3;337(6094):578-80. doi: 10.1126/science.1220759.
In predator-prey and host-parasite interactions, an individual's ability to combat an opponent often improves with experience--for example, by learning to identify enemy signals. Although learning occurs through individual experience, individuals can also assess threats from social information. Such recognition could promote the evolution of polymorphisms if socially transmitted defenses depend on enemy morph frequency. This would allow rare variants to evade detection. Female brood parasitic common cuckoos, Cuculus canorus, are either gray or rufous. The gray morph is a Batesian mimic whose hawk-like appearance deters host attack. Hosts reject this disguise through social learning, increasing their own defenses when they witness neighbors mobbing a cuckoo. Our experiments reveal that social learning is specific to the cuckoo morph that neighbors mob. Therefore, while neighbors alert hosts to local cuckoo activity, frequency-dependent social information selects for a cuckoo plumage polymorphism to thwart host detection. Our results suggest that selection for mimicry and polymorphisms comes not only from personal experience but also from social learning.
在捕食者-猎物和宿主-寄生虫相互作用中，个体对抗对手的能力通常会随着经验的增加而提高，例如通过学习识别敌人的信号。虽然学习是通过个体经验发生的，但个体也可以通过社会信息来评估威胁。如果社会传播的防御依赖于敌人形态的频率，这种识别可以促进多态性的进化。这将允许稀有变体逃避检测。雌性巢寄生的普通杜鹃， Cuculus canorus，要么是灰色的，要么是红棕色的。灰色形态是一种贝氏拟态，其鹰状外观阻止了宿主的攻击。宿主通过社会学习来识破这种伪装，当它们看到邻居驱赶杜鹃时，会增强自己的防御能力。我们的实验表明，社会学习是针对邻居驱赶的杜鹃形态的。因此，虽然邻居提醒宿主注意当地的杜鹃活动，但基于频率的社会信息选择了杜鹃羽毛的多态性来挫败宿主的检测。我们的研究结果表明，对拟态和多态性的选择不仅来自个人经验，也来自社会学习。
