Warning coloration deters predators from attacking unpalatable prey, and is often characterized by long-wavelength colors, such as orange and red. However, warning colors in nature are more diverse and include short-wavelength colors, like blue. Blue has evolved as a primary defense in some animals but is not common. One hypothesis for the maintenance of this diversity is interspecific variation in predator responses to signals. We tested this hypothesis with galliform birds: Gambel’s quail (Callipepla gambelii) and two domestic chicken breeds (Gallus gallus domesticus; Plymouth Rocks, Cochin Bantams). We measured innate avoidance and learning responses to only blue prey, only orange prey, and orange-and-blue prey, where the blue was iridescent to represent the natural coloration of the pipevine swallowtail butterfly (Battus philenor). We predicted birds would have similar responses to orange, but vary in response to blue. Upon first encounter, Cochin Bantams did not attack blue and Gambel’s quail readily attacked, indicating innate avoidance by Cochin Bantams. Plymouth Rocks had no innate aversion to any color, lower attack latencies and attacked most prey items. Cochin Bantams and Gambel’s quail both learned orange and orange-and-blue quicker than blue. Our results support the hypothesis that interspecific variation in predator response could maintain warning color diversity.

警告色可阻止掠食者攻击难吃的猎物，并且通常以长波长的颜色为特征，例如橙色和红色。但是，自然界中的警告颜色更加多样化，并且包括短波长颜色，例如蓝色。蓝色已经发展成为某些动物的主要防御能力，但并不常见。维持这种多样性的一种假设是捕食者对信号的反应中的种间变化。我们用鸡形鸟（Gambel 's quail（Callipepla gambelii）和两个家养鸡品种（Gallus gallus domesticus）对这种假设进行了检验。普利茅斯（Plymouth）岩石，科钦矮脚鸡（Cochin Bantams）。我们测量了先天回避和仅对蓝色猎物，仅橙色猎物以及橙色和蓝色猎物的学习反应，其中蓝色呈虹彩，代表the嘴燕尾蝶（Battus philenor）的自然着色。我们预测鸟类对橙色的反应相似，但对蓝色的反应则有所不同。第一次接触时，科钦矮脚鸡没有攻击蓝色，而甘贝的鹌鹑也容易受到攻击，表明科钦矮脚鸡先天回避。普利茅斯岩（Plymouth Rocks）对任何颜色都没有天生的厌恶，较低的攻击潜伏期和对大多数猎物的攻击。科钦·班塔姆斯（Cochin Bantams）和甘贝（Gambel）的鹌鹑学到的橙子和橙蓝比蓝色快。我们的结果支持这样的假说：捕食者反应中的种间差异可以维持警告色的多样性。