Male animals with more conspicuous visual and acoustic signals increase their mating success, but also increase the risk of being attacked by eavesdropping predators. In rodents, males with richer sex pheromones often...Male animals with more conspicuous visual and acoustic signals increase their mating success, but also increase the risk of being attacked by eavesdropping predators. In rodents, males with richer sex pheromones often have higher attractiveness to females, but whether or not the males are also at higher predation risk is poorly known. Here, we used 2 laboratory inbred strains of the rat Rattus norvegicus, Brown Norway （BN） and Lewis （LEW）, and wild-captured rats as odor donors to assess the relationship between the pheromone levels in male rats and attractiveness to domes- tic cats Felis catus. LEW rats had significantly higher levels of male pheromones （e.g., 4-heptanone, 2-heptanone, and 9-hydroxy-2-nonanone） than BN rats. Simultaneously, wild-captured male rats were selectively assigned to 2 groups （HIGH or LOW） based on pheromone content as determined by gas chromatography-mass spectrometry （GC-MS）. Binary choice tests were carried out during the night in the test room. We found that cats spent more time investigating male bedding and urine of LEW rats than the counterpart of BN rats. Likewise, cats also preferred bedding and urine odor of the HIGH wild rats compared with the counterparts of LOW wild rats. Adding synthetic ana- logs of the 3 pheromone ketones into the urine of either BN rats or LOW wild rats significantly increased their attractiveness to cats. Our data suggest that the rats with exaggerated male phero- mones more strongly attracted predators and thus as a consequence may suffer from elevated pre- dation risk.展开更多
基金This work was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences [XDB11010400], grants from China National Science Foundation [91231107 and 31301887], and the Foundation of State Key Laboratory of IPM [ChineseIPM1401].Acknowledgments We are grateful to Jin-Hua Zhang and You-Jin Ren for sample collection and animal care, and Jian-Guo Jiang and Gui-Jun Wen for capturing wild rats.
文摘Male animals with more conspicuous visual and acoustic signals increase their mating success, but also increase the risk of being attacked by eavesdropping predators. In rodents, males with richer sex pheromones often have higher attractiveness to females, but whether or not the males are also at higher predation risk is poorly known. Here, we used 2 laboratory inbred strains of the rat Rattus norvegicus, Brown Norway （BN） and Lewis （LEW）, and wild-captured rats as odor donors to assess the relationship between the pheromone levels in male rats and attractiveness to domes- tic cats Felis catus. LEW rats had significantly higher levels of male pheromones （e.g., 4-heptanone, 2-heptanone, and 9-hydroxy-2-nonanone） than BN rats. Simultaneously, wild-captured male rats were selectively assigned to 2 groups （HIGH or LOW） based on pheromone content as determined by gas chromatography-mass spectrometry （GC-MS）. Binary choice tests were carried out during the night in the test room. We found that cats spent more time investigating male bedding and urine of LEW rats than the counterpart of BN rats. Likewise, cats also preferred bedding and urine odor of the HIGH wild rats compared with the counterparts of LOW wild rats. Adding synthetic ana- logs of the 3 pheromone ketones into the urine of either BN rats or LOW wild rats significantly increased their attractiveness to cats. Our data suggest that the rats with exaggerated male phero- mones more strongly attracted predators and thus as a consequence may suffer from elevated pre- dation risk.
