A new member or an intruder: how do Sinai spiny mouse (Acomys dimidiatus) families respond to a male newcomer?
Abstract
Recruitment of unrelated individuals into a group plays an important role in the social life of the group living animals. The main goal of our study was to analyze the reactions of established, breeding families of the Sinai spiny mouse, Acomys dimidiatus (Muridae, Rodentia) to male newcomers in the presence and the absence of a breeding resident male.
We compared the behaviour of family members of different sex or age to the presence of a new male. Only a few aggressive and/or non-aggressive types of contacts occurred before and one month after the addition of the new male.
During the experiment, both types of contacts arose, but the results were highly variable. Increased aggressive behaviour of the family toward the intruder was explained mainly by the presence of pregnant or lactating females, which suggests that aggression towards a male newcomer is associated with the reproductive status of females.