Many animals decorate their exterior with environmental materials, and these decorations are predicted to increase their survival. The adaptive significance of these decorations, however, has seldom been tested experimentally under field conditions. This study researched the anti‐predatory functions of the decoration (bag) of a bagworm moth, Eumeta crameri, against their natural predator, Oecophylla smaragdina, the Asian weaver ant. The study experimentally tested if bag removal from caterpillars resulted in more predation than bagged caterpillars under field conditions, which would support the hypothesis that bags are selected to protect the caterpillars against their predators. In support of the prediction, this study showed that caterpillars without a bag were attacked, killed, and taken to ants' nests significantly more than bagged caterpillars. The study provides rare experimental evidence for the anti‐predatory functions of the decoration under field conditions. This study suggests that decorating behaviour has evolved in animals as an anti‐predatory defence mechanism.

中文翻译：

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袋虫装饰是一种防掠食性结构

许多动物用环保材料装饰它们的外表，预计这些装饰可以提高它们的生存率。然而，这些装饰的适应性意义很少在现场条件下进行实验测试。本研究研究了袋螟蛾 Eumeta crameri 的装饰物（袋子）对它们的天敌 Oecophylla smaragdina（亚洲织布蚁）的抗捕食功能。该研究通过实验测试了在田间条件下，从毛毛虫身上取出袋子是否会导致比袋装毛虫更多的捕食，这将支持选择袋子来保护毛毛虫免受捕食者侵害的假设。为了支持这一预测，这项研究表明，没有袋子的毛毛虫被攻击、杀死并带到蚂蚁的 筑巢的次数明显多于袋装毛虫。该研究为装饰在野外条件下的抗捕食功能提供了罕见的实验证据。这项研究表明，装饰行为已经在动物中进化为一种反掠夺性防御机制。