Social recognition in paired but not single male prairie voles.

Social recognition is an integral component of behavior that underlies many much larger behavioral suites. For example, monogamous pair bonding is relatively meaningless if an individual cannot recall with whom the bond was with. Prairie voles (Microtus ochrogaster) are a socially monogamous rodent, well known for their long-term pair bonds between males and females. Although previous work has shown that bonded males reliably spend more time with their pair-mate over an unfamiliar female, recent work has demonstrated that single male prairie voles do not discriminate between females. This discrepancy raises the important question: do paired males distinguish between non-mate females? We asked whether pair bonding alters the expression of social recognition in male voles by comparing social recognition of single and pair bonded males using the habituation/dishabituation paradigm. We found that pair bonded, but not single male prairie voles exhibit social recognition of (non-mate) females, suggesting a shift in cognitive behavior after pair bond formation. This difference is not due to differences in motivation to engage in social exchanges, as males attempted to contact unfamiliar females at similar levels. Based on these data, we speculate that the stage of life (single or bonded) influences the relevance of attending to social information of same- and opposite-sex conspecifics.