Triadic male-infant-male interaction serves in bond maintenance in male Assamese macaques

Abstract

While the ultimate consequences of social bonds start to be better understood, the proximate behavioural mechanisms underlying the formation and maintenance of these close affiliative relationships have received less attention. We investigated the possible function of male-infant-male interactions (MIMIs) in male-male social bonding processes by analysing about 9000h of focal animal observations collected on two groups of wild Assamese macaques. In support of an agonistic buffering function of MIMIs, after engaging in a MIMI upon approach, subordinates stayed longer in close proximity of a dominant male. Overall, the frequency of MIMIs increased the stronger the affiliative relationship between two males, suggesting that MIMIs like grooming function in relationship maintenance. We did not find support for a role of MIMIs in bond formation as the frequency of MIMIs did not affect the time a male dyad spent in proximity in the consecutive year. Our results contribute to the general debate on behaviours influencing social dynamics in group living mammals.

The male and female perspective in the link between male infant care and mating behaviour in Barbary macaques

“…In accordance with the 'extended mating effort hypothesis', however, (Kalbitz et al, 2017;Kuběnová et al, 2019;Paul et al, 1996, Taub 1980b). The stable pattern may reduce competition over infants used in these interactions (Kalbitz et al, 2017;Paul et al, 1996) and make those interactions more effective tools for male relationship management (Kubenova et al, 2017;Ogawa, 1995;Paul et al, 1996).…”

“…An alternative, non‐mutually exclusive driver of male care, particularly in Barbary macaques, is improved access to infants for frequent triadic man–infant–man interactions. These interactions help males to establish and maintain social bonds with other males (Kalbitz et al, ; Kuběnová et al, ; Kümmerli & Martin, ; Paul et al, ) which may reduce aggression among males (Deag & Crook, ) and help them to retain support in coalition (Paul et al, ). The benefit of social bonding may outweigh the cost of infant care.…”

“…Enduring male–female relationship may also result in stability in male infant care, that is males taking care of consecutive offspring of the same females. Specifically, in Barbary macaques this stability may be beneficial in relation to the high frequency of man–infant–man interactions, during which two males manipulate one infant together and which help males to manage relationships with other males (Kalbitz et al, ; Kuběnová et al, ; Paul et al, , Taub ). The stable pattern may reduce competition over infants used in these interactions (Kalbitz et al, ; Paul et al, ) and make those interactions more effective tools for male relationship management (Kubenova et al, ; Ogawa, ; Paul et al, ).…”

“…Both interaction types are unevenly distributed among males as well as infants (Deag, 1980;Kubenova et al, 2017;Ménard et al, 2001;Taub, 1984). Triadic man-infant-man interactions in macaques are proposed to primarily serve a social function among males (Deag & Crook, 1971;Kalbitz, Schülke, & Ostner, 2017;Paul et al, 1996), but explanations for dyadic male-infant interactions remain inconclusive (e.g. Paul et al, 1996;Taub, 1980b).…”

Testosterone and cortisol are negatively associated with ritualized bonding behavior in male macaques

“…Barbary macaques prefer to form coalitions with closely bonded partners (Young et al,128 2014b) this supports the notion that male-infant-male interactions indeed serve to form 129 social bonds (Kalbitz et al, 2017;Paul et al, 1996). Another proposed function for male-130 infant-male interactions is that infants may be used as an 'agonistic buffer', to allow two 131 males to approach each other in a non-threatening context (Deag and Crook, 1971;Paul et 132 al., 1996).…”