Gamberale-Stille G, Tullberg B S
Department of Zoology, Stockholm University, S-106 91 Stockholm, Sweden.
Proc Biol Sci. 2001 Dec 22;268(1485):2525-9. doi: 10.1098/rspb.2001.1814.
Colours are common stimuli in signalling systems. Requirements to function well as a signal sometimes conflict between different signallers, and the same colour stimulus is used to convey completely different messages to the same receiver. Fruits and aposematic insects both use red coloration as a signal, in the former case to signal profitability and in the latter case as a warning signal. In two experiments, we investigated whether the domestic chick, an omnivorous predator, differed in its unconditioned preference or avoidance of red and green stimuli depending on whether or not the stimulus was an insect. The experiments were designed as preference tests between red and green painted prey. The prey were live insects and artificial fruits (experiment 1), and, to investigate the effect of movement, live and dead insects (experiment 2). The chicks did not show any difference in pecking preference between red and green when fruit-like stimuli were used, but when the prey were insects, green prey were strongly preferred to red prey, and prey movement did not affect this bias. Thus, young chicks may recognize prey as insects and then discriminate between different prey colorations, or one type of food may elicit an unlearned colour preference-avoidance response that is absent with another type of food.
颜色是信号系统中常见的刺激因素。作为一种信号要良好发挥作用的要求，在不同信号发送者之间有时会相互冲突，并且相同的颜色刺激会被用于向同一接收者传达完全不同的信息。果实和具警戒色的昆虫都将红色作为一种信号，在前一种情况下是为了表明有利可图，而在后一种情况下则作为一种警告信号。在两项实验中，我们研究了作为杂食性捕食者的家鸡，对于红色和绿色刺激的无条件偏好或回避是否会因其是否为昆虫而有所不同。实验设计为红色和绿色涂漆猎物之间的偏好测试。猎物包括活昆虫和人工果实（实验1），并且，为了研究运动的影响，还包括活昆虫和死昆虫（实验2）。当使用类似果实的刺激物时，雏鸡在啄食红色和绿色猎物之间没有表现出任何差异，但当猎物是昆虫时，绿色猎物比红色猎物更受强烈偏好，并且猎物的运动并未影响这种偏好倾向。因此，幼雏可能会将猎物识别为昆虫，然后区分不同猎物的颜色，或者一种食物可能会引发一种未经学习的颜色偏好 - 回避反应，而另一种食物则不会引发这种反应。
