Mella Valentina S A, Cooper Christine E, Davies Stephen J J F
Department of Environment and Agriculture, Curtin University, Perth, WA 6845, Australia.
Curr Zool. 2016 Feb;62(1):53-59. doi: 10.1093/cz/zov005. Epub 2016 Feb 10.
Predator odors can elicit fear responses in prey and predator odor recognition is generally associated with physiological responses. Prey species are often more likely to respond to the odor of familiar rather than alien predators. However, predator naïvety in an introduced prey species has rarely been investigated. We examined the physiological response, as shown by changes in ventilatory variables, of an introduced terrestrial herbivore, the European rabbit , in Australia, to the odor of potential predators and to control odors (distilled water and horse), to explore if responses were limited to historical (cat and fox) predators, or extended to historically novel predators (snake and quoll). All odors except distilled water elicited a response, with rabbits showing long-term higher respiratory frequencies and lower tidal volumes after introduction of the odors, indicating an increase in alertness. However, the intensity of the rabbits' reaction could not be directly linked to any pattern of response with respect to the history of predator-prey relationships. Rabbits exhibited significantly stronger reactions in response to both cat and quoll odors than they did to distilled water, but responses to horse, fox, and snake odor were similar to that of water. Our results show that the introduced rabbit can respond to both historical and novel predators in Australia, and suggest that shared evolutionary history is not necessarily a prerequisite to predator odor recognition.
捕食者的气味会引发猎物的恐惧反应，而捕食者气味识别通常与生理反应相关。猎物物种通常更有可能对熟悉的捕食者的气味做出反应，而不是陌生捕食者的气味。然而，对于引入的猎物物种中捕食者的幼稚性研究甚少。我们研究了引入的陆生食草动物——澳大利亚的欧洲兔，对潜在捕食者的气味以及对照气味（蒸馏水和马的气味）的生理反应，通过通气变量的变化来体现，以探究其反应是否仅限于历史上的（猫和狐狸）捕食者，还是会扩展到历史上的新捕食者（蛇和袋鼬）。除蒸馏水外，所有气味都引发了反应，兔子在接触气味后表现出长期较高的呼吸频率和较低的潮气量，表明警觉性提高。然而，兔子反应的强度与捕食者 - 猎物关系历史的任何反应模式都没有直接联系。兔子对猫和袋鼬气味的反应明显比对蒸馏水的反应更强，但对马、狐狸和蛇气味的反应与对水的反应相似。我们的结果表明，引入的兔子能够对澳大利亚历史上的和新出现的捕食者都做出反应，并表明共同的进化历史不一定是捕食者气味识别的先决条件。
