Abstract Many rodents exhibit inducible defenses when exposed to chemical cues from mammalian predators. These responses may include delays in sexual maturation, smaller adult body size and decreases in litter size an...Abstract Many rodents exhibit inducible defenses when exposed to chemical cues from mammalian predators. These responses may include delays in sexual maturation, smaller adult body size and decreases in litter size and pup weight. We exposed the hybrid juvenile offspring of field-caught and lab-descended house mice Mus musculus to the chemical cues of mouse-fed or chick-fed kingsnakes, Lampropeltis getula, for 20 days after weaning, to examine the effects of ophidian predator cues on prey development. We hypothesized that these cues would elicit inducible defenses such as alteration of growth rates, and/or the timing of reproductive development in mice. Once mature, the reproductive effort of the mice might also be impacted by producing smaller litter sizes or lighter pups or not reproducing at all. We found no effect of kingsnake cues on any of the measures. These findings support the hypothesis that inducible defenses may have evolved as a strategy to deal with specific predators.展开更多
The main goal of the paper was to determine the habitat distribution of the house mouse(Mus musculus)within a rural landscape of Buenos Aires province,Argentina.We also studied the seasonal variation in abundance and ...The main goal of the paper was to determine the habitat distribution of the house mouse(Mus musculus)within a rural landscape of Buenos Aires province,Argentina.We also studied the seasonal variation in abundance and reproductive activity.The habitats studied were poultry farms,human houses in a small village,cropfields,pastures,cropfield and pasture edges,riparian habitats(streams),railway embankments and woodlots.We captured 817 M.musculus and 690 individuals of 5 native rodent species.M.musculus was captured in poultry farms,houses,riparian habitats,cropfield and borders,but it showed a significantly higher abundance in poultry farms compared to the other habitats.Its presence outside poultry farms was significantly related to the distance to streams and poultry farms.The mean trapping success index of M.musculus did not show significant variations between periods,but the proportion of active males was significantly higher in the spring-summer period than in the autumn-winter period.All captures of M.musculus in cropfields,borders and riparian habitats occurred in the spring-summer period.The capture of M.musculus in many types of habitats suggests that it can disperse outside poultry farms,and streams may be used as corridors.展开更多
文摘Abstract Many rodents exhibit inducible defenses when exposed to chemical cues from mammalian predators. These responses may include delays in sexual maturation, smaller adult body size and decreases in litter size and pup weight. We exposed the hybrid juvenile offspring of field-caught and lab-descended house mice Mus musculus to the chemical cues of mouse-fed or chick-fed kingsnakes, Lampropeltis getula, for 20 days after weaning, to examine the effects of ophidian predator cues on prey development. We hypothesized that these cues would elicit inducible defenses such as alteration of growth rates, and/or the timing of reproductive development in mice. Once mature, the reproductive effort of the mice might also be impacted by producing smaller litter sizes or lighter pups or not reproducing at all. We found no effect of kingsnake cues on any of the measures. These findings support the hypothesis that inducible defenses may have evolved as a strategy to deal with specific predators.
基金funded by Universidad de Buenos Aires(UBACYT X098)Agencia Nacional de Promoción Científica y Técnica(ANPCYT,PICT 12303 and 33513)grants.
文摘The main goal of the paper was to determine the habitat distribution of the house mouse(Mus musculus)within a rural landscape of Buenos Aires province,Argentina.We also studied the seasonal variation in abundance and reproductive activity.The habitats studied were poultry farms,human houses in a small village,cropfields,pastures,cropfield and pasture edges,riparian habitats(streams),railway embankments and woodlots.We captured 817 M.musculus and 690 individuals of 5 native rodent species.M.musculus was captured in poultry farms,houses,riparian habitats,cropfield and borders,but it showed a significantly higher abundance in poultry farms compared to the other habitats.Its presence outside poultry farms was significantly related to the distance to streams and poultry farms.The mean trapping success index of M.musculus did not show significant variations between periods,but the proportion of active males was significantly higher in the spring-summer period than in the autumn-winter period.All captures of M.musculus in cropfields,borders and riparian habitats occurred in the spring-summer period.The capture of M.musculus in many types of habitats suggests that it can disperse outside poultry farms,and streams may be used as corridors.
