scholarly journals Exploring the Cognitive Capacities of Japanese Macaques in a Cooperation Game

Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1497
Author(s):  
Ryan Sigmundson ◽  
Mathieu S. Stribos ◽  
Roy Hammer ◽  
Julia Herzele ◽  
Lena S. Pflüger ◽  
...  

Cooperation occurs amongst individuals embedded in a social environment. Consequently, cooperative interactions involve a variety of persistent social influences such as the dynamics of partner choice and reward division. To test for the effects of such dynamics, we conducted cooperation experiments in a captive population of Japanese macaques (Macaca fuscata, N = 164) using a modified version of the loose-string paradigm in an open-experiment design. We show that in addition to becoming more proficient cooperators over the course of the experiments, some of the macaques showed sensitivity to the presence of potential partners and adjusted their behavior accordingly. Furthermore, following an unequal reward division, individuals receiving a lesser reward were more likely to display aggressive and stress-related behaviors. Our experiments demonstrate that Japanese macaques have some understanding of the contingencies involved in cooperation as well as a sensitivity to the subsequent reward division suggestive of an aversion to inequity.

Behaviour ◽  
1974 ◽  
Vol 49 (1-2) ◽  
pp. 152-195 ◽  
Author(s):  
Jeannette P. Hanby ◽  
Conrad E. Brown

AbstractSociosexual behaviours were observed over a two-year period in a natural troop of about 100 Japanese macaques (Macaca fuscata) confined in a two-acre corral. The development and mature expression of integrated patterns of mounting, presenting, thrusting, and related behaviours were examined. The frequency and type of mounting varied dramatically with the season of the year. Male-female, female-male, and female-female mounting were most frequent during the 6-month breeding season when males 4½ years and older can ejaculate and females 3½ years and older can conceive. Ejaculation generally occurred only after a series of mounts. Mountings in series by and on either sex were largely confined to the breeding season. Female presenting and male thrusting and certain other behaviours accompanied mounting more often at that time of year also. In the nonbreeding season, heterosexual interactions decreased but male-male mounting increased though it never reached breeding season levels for male-female mounting. Nonbreeding season mount events between both sexes and all ages typically involved only a single mount, but most were accompanied by thrusts. The type of interaction between pair members also differed; most mounting occurred during play. In males, mounting and thrusting were integrated gradually according to the season and sex of partner. By six months of age, males oriented to a partner's buttocks and used a double-foot-clasp posture on most mounts. At 1½ males mounted females more frequently than males and by 2½ showed the seasonal cycles in mount frequency and partner choice. They reached peaks in mount event frequency at 4½, but the most efficient and stable patterns were seen in males over 7 years of age. Although females showed thrusting movements early in life, they seldom mounted except on males during breeding season and occasionally during play or agonistic situations. They were most active as mount partners and actors after 3½ years of age. Their subsequent activity varied with the individual and her reproductive state. Several conclusions can be drawn from this and other studies on the development of sociosexual behaviours in primates. 1. Rearing conditions are crucial to the development and integration of postures, thrusting, intromission, and ejaculation. The most important element for normal development is the mother; however, the presence of other adult and encouraging females helps a young male to integrate the various elements. Peer males and females also facilitate or allow the expression of a variety of patterns and probably provide a source of enduring attachments and mature partner preferences. The role of the adult males in development is both positive and negative depending on the male, the group, and the species. 2. The most important aspect of normal sociosexual development is the differentiation and integration of elements such as mounting, presenting, thrusting, intromission into two patterns : the primarily copulatory and the primarily contacting. Intromission seems to be a key element in the differentiation process. Factors that facilitate intromission speed the process; factors that inhibit intromission delay the development of the young primate male's ability to distinguish correctly between postures, partners, and situations. The copulatory patterns of females seem less affected by unsatisfactory rearing conditions, but the sociosexual patterns of contact may be disturbed. 3. Mature sociosexual patterns develop from close physical contact with the mother or mother substitutes. Erection and thrusting appear independently but soon become linked to ventral clinging, embracing, riding, and mounting. Mount and present postures develop quickly and vary according to species and pairings and contexts. The most stereotyped posturing and patterns appear in the copulatory context: the sociosexual patterns retain their variability in form and variety of expression in different contexts, mainly affiliative and more rarely, agonistic,


Behaviour ◽  
2013 ◽  
Vol 150 (11) ◽  
pp. 1225-1254 ◽  
Author(s):  
Noëlle Gunst ◽  
Jean-Baptiste Leca ◽  
Paul L. Vasey

The emergence of conceptive and non-conceptive sexual behaviours in mature individuals can be traced back to immature socio-sexual behavioural patterns. We tested the ‘needing-to-learn hypothesis’ in the development of sexual behaviours in the immature male Japanese macaques of Arashiyama, Japan. This hypothesis holds that juvenility serves to provide young individuals with a period in which to practice adult male-like sexual and socio-sexual behaviours and partner choice. Our cross-sectional focal data on mounting behaviour and partner choice in juvenile males (1–3 years) supported most of our predictions: (1) as they became older and learnt more effective patterns of sexual solicitations, juvenile males performed more demonstrative solicitations and less non-demonstrative solicitations, (2) the frequency of mounts performed by juvenile males increased with age and converged on a frequency of mounts typical of adult males, (3) the frequency of mounts reflecting underachievement (i.e., improperly oriented mounts and single/no foot-clasp mounts) decreased as juvenile males became older, (4) the double foot-clasp mounting posture became gradually more common in juvenile males over time, while other mounting postures became less common and (5) from two to three years old, the frequency of males’ sexual mounts directed to adult females increased. Such timelines of gradual increase in the frequency of effective adult-like behavioural patterns and gradual decrease in the frequency of less effective immature behavioural patterns are consistent with the ‘needing-to-learn hypothesis’ emphasizing the role of age and practice in the progressive acquisition of adult-like sexual behaviour, mounting skills, and partner age choice during male juvenility.


2007 ◽  
Vol 121 (2) ◽  
pp. 181-188 ◽  
Author(s):  
Gabriele Schino ◽  
Eugenia Polizzi di Sorrentino ◽  
Barbara Tiddi

Behaviour ◽  
2001 ◽  
Vol 138 (4) ◽  
pp. 487-509 ◽  
Author(s):  
Bernard Chapais ◽  
Patrick Belisle

AbstractWe analyzed co-feeding in relation to degree of kinship in Japanese macaques Macaca fuscata), testing experimentally five categories of matrilineal kin dyads: mother-daughter, grandmother-granddaughter, sisters, aunt-niece and nonkin. In each test, two adult females with a clear dominance relationship had access to a box containing a limited quantity of highly prized food. The dominant female could easily prevent the subordinate from eating so that food was easily monopolizable, hence the use of the expression tolerated co-feeding. Rates of tolerated co-feeding increased steeply with degree of kinship. The aggression levels of dominant females towards subordinate females decreased with increasing degree of kinship and this effect was most apparent between mothers and daughters. The confidence level of subordinate females increased with degree of kinship and this effect became apparent above the aunt-niece kin class. Prior access to food by the subordinate female was a significant means of access to food, mostly beyond the grandmother-granddaughter kin category. The results point to a relatedness threshold for the preferential treatment of kin at r = 0.25 (grandmother-granddaughter and sister dyads), beyond which (r = 0.125: aunt-niece dyads), levels of tolerated co-feeding were comparable to those of nonkin females. The identity of this threshold with that found in previous studies on the same group for two different types of interactions suggests the existence of a generalized relatedness threshold for kin favoritism in Japanese macaques. Assuming that the costs of food defense by the dominant females were negligible and that tolerated co-feeding was altruistic, our results support the role of kin selection in the evolution of altruism in primates beyond the mother-offspring bond.


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