Social functions of allogrooming in cooperatively breeding meerkats

In social mammals, grooming may be used in care of offspring, to maintain pair bonds, or to placate dominant individuals. We examined grooming patterns in groups of the cooperatively breeding meerkat, Suricata suricatta. Dominant females produce over 80% of litters, but older subordinate females occasionally breed. Grooming between dominant individuals was the most common and symmetrical interaction. The dominant female received more and gave less in grooming interactions with subordinates. The dominant female groomed younger subordinates more frequently than older subordinates, suggesting that grooming by dominant females represents parental care, and also reflects the reproductive conflict between females. Older subordinates groomed the dominant female more frequently than did younger subordinates. Subordinates that were frequently attacked by the dominant female groomed her for longer durations than those that were not, and the duration of dominant female grooming by subordinates increased as birth of the dominant female's pups approached. These results support the idea that subordinates use grooming to placate the dominant female. Analysis of ‘immediate reciprocity’ (whether the groomee returned grooming of the groomer within the grooming bout) showed that subordinate females reciprocated more frequently than subordinate males when the dominant female initiated grooming. However, the dominant female reciprocated subordinate females less frequently than she did subordinate males. This suggests that the need to placate the dominant female may be higher for subordinate females than for subordinate males, possibly because of the risk of eviction caused by reproductive conflict between females.