LAUSR

Pair bonding (i.e. individuals showing a preference for a specific opposite-sex individual) has been demonstrated in several socially monogamous species. However, social bonds also occur in nonmonogamous species, but have received less attention. Currently, we do not know whether social bonds in monogamous pairs differ from social bonds in polygynous groups. We studied the socially flexible African striped mouse in the laboratory, conducting 3 h partner preference tests typically used to measure pair bonds in socially monogamous prairie voles, Microtus ochrogaster. In the field, striped mice typically live in polygynous groups, but socially monogamous pairs have also been observed. We compared social bonds between 12 monogamous pairs and 12 polygynous groups (1 male and 2 females). The social situation (monogamous versus polygynous) did not influence social bonds. Female striped mice showed a preference for their partner. While males spent more time in body contact with their partner, they showed a sexual preference for strange females. Polygynous males did not show a preference for one of their two females. While significant preferences for partners were found in striped mice, social preference was less strong than that reported for socially monogamous prairie voles. In summary, our results suggest that opposite-sex social bonds not only occur in monogamous species but also in species that live in polygynous groups, but that these bonds might be weaker in polygynous species.