Artificial selection for short and long attack latencies in wild Mus musculus domesticus

Artificial selection for short and long attack latency levels in wild male Mus musculus over 11 generations was successful for short latencies. The realized heritability of 0.30 is comparable to those found in other selection studies on aggression. In part selection may have been for faster onto-genetic development of short attack latencies. Four attempts to select for longer attack latencies failed because the lines died out immediately or within two generations for unknown reasons. But neither the physical condition of the animals nor their behavior appeared to have been the cause. Female aggressiveness as measured in female-female encounters was not affected by the selection exerted on the males. This suggests that no genetic correlation exists between aggressiveness of males and females, confirming results of P. D. Ebert and J. S. Hyde [(1976). Behav. Genet. 6:291-304] obtained in a selection experiment on aggression using females.