Female odors and aggression among male Microtus

The effect of various female odors on agonistic interaction among grouped male prairie voles ( Microtus ochrogaster) was investigated. An increased number of investigative behavioral interactions among the males followed the introduction of female odors. The intensity of behavioral response depended on the source of the odor, the sexual experience of the males, and the ongoing behavior of the group. The greatest number of agonistic and attempted sexual interactions occurred among experienced males following introduction of urine from estrous females. The presentation of female odors, even to males already engaged in fighting, did not decrease aggressive interactions as is reported for Mus musculus. The changes elicited in male behavior by female odors are viewed not as a response to any presumed releaser pheromone but rather as the result of confusion in communication between males, since previous experience with those odors introduced involved sexual interaction with females.