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 ra- ther than ...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 ra- ther than alien predators. However, predator na＇ivety in an introduced prey species has rarely been investigated. We examined the physiological response, as shown by changes in ventilatory vari- ables, of an introduced terrestrial herbivore, the European rabbit Oryctolagus cuniculus, in Australia, to the odor of potential predators and to control odors （distilled water and horse）, to explore if res- ponses 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, indi- cating 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 dis- tilled 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.展开更多
Predation risk is one of the most important selective forces in nature and has significant effects on the behavior and physiology of prey individuals.Prey species have evolved several different traits to reduce and av...Predation risk is one of the most important selective forces in nature and has significant effects on the behavior and physiology of prey individuals.Prey species have evolved several different traits to reduce and avoid this predation pressure.This research aimed to determine the behavioral and physiological responses of striped field mice to predator risk.In the present study,we compared the agonistic behavior in male and female striped field mice(Apodemus agrarius Pallas,1771)of the same sexes under the odor derived from a male Himalayan weasel(Mustela sibirica).Dyads were subjected to 5 min staged encounters in neutral arenas once a week for 3 weeks during which agonistic and social behaviors were recorded and fecal hormone concentrations were determined using pre-column derivatization and high performance liquid chromatography methods.Furthermore,we also tested the effects of weasel odor on the adrenal glands.The results showed that:(i)male striped field mice did not exhibit any change in body weight and physiological characteristics but their aggressive behavior changed over time,and(ii)females responded to predation risk by significantly decreasing body mass and through increases in fecal cortisol levels and adrenal gland indices.These data show significant sex differences in the body weight,adrenal gland indices and fecal cortisol levels of striped field mouse under predation risk.展开更多
文摘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 ra- ther than alien predators. However, predator na＇ivety in an introduced prey species has rarely been investigated. We examined the physiological response, as shown by changes in ventilatory vari- ables, of an introduced terrestrial herbivore, the European rabbit Oryctolagus cuniculus, in Australia, to the odor of potential predators and to control odors （distilled water and horse）, to explore if res- ponses 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, indi- cating 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 dis- tilled 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.
基金This research was financially supported by the National Basic Research Program of China(No.2007CB109106).
文摘Predation risk is one of the most important selective forces in nature and has significant effects on the behavior and physiology of prey individuals.Prey species have evolved several different traits to reduce and avoid this predation pressure.This research aimed to determine the behavioral and physiological responses of striped field mice to predator risk.In the present study,we compared the agonistic behavior in male and female striped field mice(Apodemus agrarius Pallas,1771)of the same sexes under the odor derived from a male Himalayan weasel(Mustela sibirica).Dyads were subjected to 5 min staged encounters in neutral arenas once a week for 3 weeks during which agonistic and social behaviors were recorded and fecal hormone concentrations were determined using pre-column derivatization and high performance liquid chromatography methods.Furthermore,we also tested the effects of weasel odor on the adrenal glands.The results showed that:(i)male striped field mice did not exhibit any change in body weight and physiological characteristics but their aggressive behavior changed over time,and(ii)females responded to predation risk by significantly decreasing body mass and through increases in fecal cortisol levels and adrenal gland indices.These data show significant sex differences in the body weight,adrenal gland indices and fecal cortisol levels of striped field mouse under predation risk.
