Focused grooming networks and stress alleviation in wild female baboons

Abstract

We examine the relationship between glucocorticoid (GC) levels and grooming behavior in wild female baboons during a period of instability in the alpha male rank position. All females' GC levels rose significantly at the onset of the unstable period, though levels in females who were at lower risk of infanticide began to decrease sooner in the following weeks. Three factors suggest that females relied on a focused grooming network as a coping mechanism to alleviate stress. First, all females' grooming networks became less diverse in the weeks following the initial upheaval. Second, females whose grooming had already focused on a few predictable partners showed a less dramatic rise in GC levels than females whose grooming network had been more diverse. Third, females who contracted their grooming network the most experienced a greater decrease in GC levels in the following week. We conclude that close bonds with a few preferred partners allow female baboons to alleviate the stress associated with social instability.

Heritable victimization and the benefits of agonistic relationships

“…This approach led us to a unique view of agonistic relationships, namely, that they are somehow beneficial. Previous studies linking social bonds and reproductive success have primarily focused on affiliative interactions (2), because such relationships have more immediate and obvious benefits [e.g., reduced stress (31,32), enhanced immune competence (33)]. However, we found that the extent to which a marmot is integrated and centrally positioned in its agonistic network positively covaries with LRS and longevity.…”

Associations between glucocorticoids and sociality across a continuum of vertebrate social behavior

“…This study showed that Adele penguins treated with high dose GCs (within the stress‐induced range) subsequently increased their affiliative (nonsexual pair‐bonding) behavior (Thierry, Brajon, Spée, & Raclot, 2014). However, instability in primate social groups (e.g., unstable dominance hierarchy) that is known to elevate GCs in group members (Creel, Dantzer, Goymann, & Rubenstein, 2013) did not affect the amount of nonsexual bonding behavior but was associated with same amount of bonding behavior (grooming) being focused to fewer group recipients (Crockford, Wittig, Whitten, Seyfarth, & Cheney, 2008; Wittig et al., 2008). …”

“…On the other hand, chronic stress may also have opposite effects, tying social groups together. For example, exposure to chronic stress is known to tighten social networks, which results in cooperative or affiliative behavior limited more strictly to a group of close relatives or allies (humans: Dunbar & Spoors, 1995; Kornienko, Clemans, Out, & Granger, 2014; in other species: Zhou, Sornette, Hill, & Dunbar, 2005; baboons: Crockford et al., 2008; Wittig et al., 2008). Consequently, chronic stress may promote in‐group cooperation but also out‐group aggression (Puurtinen, Heap, & Mappes, 2014).…”

Social bonds between unrelated females increase reproductive success in feral horses

“…If aggression reduces female fecundity and a counterstrategy involves long-term stable social relationships between females, the formation of affiliative social bonds may be an adaptive strategy. Also, affiliative social interactions have immediate benefits to individuals, such as reduced heart rate in horses (7), reduced stress in guinea pigs and baboons (8,9), and enhanced immune competence in macaques (10). Therefore, affiliative relationships could have profound impacts on fitness.…”