Role of vocal tract characteristics in individual discrimination by Japanese macaques (Macaca fuscata)

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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Variation in intergroup encounters among two provisioned free-ranging populations of Japanese macaques Macaca fuscata

Current Zoology ◽

10.1093/czoolo/58.4.517 ◽

2012 ◽

Vol 58 (4) ◽

pp. 517-524 ◽

Cited By ~ 1

Author(s):

Peng Zhang ◽

Kunio Watanabe

Keyword(s):

Social Factors ◽

Intergroup Relations ◽

Macaca Fuscata ◽

Japanese Macaque ◽

Japanese Macaques ◽

Intergroup Relationships ◽

Specific Variation ◽

Intergroup Encounters ◽

Free Ranging

Abstract Typically, Japanese macaques are thought to avoid encountering other groups wherever possible. Intergroup relations between macaques on Shodoshima Island, however, appear exceptional. We show that neighboring groups of Shodoshima monkeys spent 32.8% of their active time in proximity to (<100 m) and even foraged simultaneously at the same provisioning site with another group. The average duration and rate of intergroup encounters at Shodoshima (59.8 min, 0.33 times/hour, n=269) were approximately ten times longer and 16.5 times more frequent than those at Jigokudani (6.1 min, 0.02 times/hour, n=14). Since both populations have similar provisioning and ecological conditions, such variation cannot be explained by the socioecology model alone. Compared with other populations of Japanese macaques, intergroup relations of Shodoshima monkeys are also characterized by more frequent neutral encounters, less frequent agonistic encounters, more frequent unsuccessful displacement, a lower intensity of aggression, and more frequent counter-aggression between groups. These characteristics suggest that intergroup relationships on Shodoshima Island are more tolerant than those in other Japanese macaque populations. This study reveals considerable differences in intergroup encounters within local populations of Japanese macaques living in similar environments, and emphasizes the role of social factors in such intra-specific variation.

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Development of sexual and socio-sexual behaviours in free-ranging juvenile male Japanese macaques, Macaca fuscata

Behaviour ◽

10.1163/1568539x-00003088 ◽

2013 ◽

Vol 150 (11) ◽

pp. 1225-1254 ◽

Cited By ~ 16

Author(s):

Noëlle Gunst ◽

Jean-Baptiste Leca ◽

Paul L. Vasey

Keyword(s):

Macaca Fuscata ◽

Japanese Macaques ◽

Partner Choice ◽

Adult Males ◽

Cross Sectional ◽

Sexual Behaviours ◽

Behavioural Patterns ◽

Juvenile Males ◽

Free Ranging

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.

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The Social Rank of Zoo-Housed Japanese Macaques is a Predictor of Visitor-Directed Aggression

Animals ◽

10.3390/ani9060316 ◽

2019 ◽

Vol 9 (6) ◽

pp. 316 ◽

Cited By ~ 3

Author(s):

Jocelyn M. Woods ◽

Stephen R. Ross ◽

Katherine A. Cronin

Keyword(s):

Macaca Fuscata ◽

Social Dynamics ◽

Social Rank ◽

Japanese Macaques ◽

Activity Levels ◽

The Social ◽

Rating Method ◽

Lower Ranking ◽

Crowd Size

The effect that visitors have on the behavior and welfare of animals is a widely-studied topic in zoo animal welfare. Typically, these studies focus on how the presence or activity levels of visitors affect animals. However, for many species, and particularly primates, social factors, such as social rank, can also have a large impact on behavior. Here, we considered the influence of both the role of visitors (crowd size and activity levels) and rank on the occurrence of visitor-directed aggression by zoo-housed Japanese macaques (Macaca fuscata, N = 12). We conducted 52 weeks of observation (443.8 h) of macaques living in a large outdoor habitat and recorded 1574 events of visitor-directed behavior, 94.2% of which was characterized as aggressive. We calculated rank using the Elo-rating method. GLMM comparisons indicate that rank was a significant predictor of visitor-directed aggression, with lower-ranked individuals displaying more frequent aggression towards visitors. Additionally, visitor-directed aggression differed by crowd activity levels, but not crowd size. These results support our prediction that rank is associated with differences in visitor-directed aggression, and we interpret this pattern as lower-ranking macaques redirecting aggression toward zoo visitors as safe targets. This work emphasizes how factors emanating from the zoo environment can combine with social dynamics to influence primate response to human presence in the zoo setting.

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The role of vocal-tract characteristics and pitch patterns in identifying individuality in Coo calls of Japanese macaques

Frontiers in Behavioral Neuroscience ◽

10.3389/conf.fnbeh.2012.27.00246 ◽

2012 ◽

Vol 6 ◽

Author(s):

Riquimaroux Hiroshi

Keyword(s):

Vocal Tract ◽

Japanese Macaques ◽

Pitch Patterns

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The role of Japanese macaques (Macaca fuscata) as endozoochorous seed dispersers on Kinkazan Island, northern Japan

Mammalian Biology ◽

10.1016/j.mambio.2011.01.001 ◽

2011 ◽

Vol 76 (5) ◽

pp. 525-533 ◽

Cited By ~ 19

Author(s):

Yamato Tsuji ◽

Kaede Sato ◽

Yoshikazu Sato

Keyword(s):

Macaca Fuscata ◽

Japanese Macaques ◽

Seed Dispersers ◽

Northern Japan

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Learning Speech Production and Perception through Sensorimotor Interactions

Cerebral Cortex Communications ◽

10.1093/texcom/tgaa091 ◽

2020 ◽

Author(s):

Shihab Shamma ◽

Prachi Patel ◽

Shoutik Mukherjee ◽

Guilhem Marion ◽

Bahar Khalighinejad ◽

...

Keyword(s):

Vocal Tract ◽

Human Subjects ◽

Motor Task ◽

Neural Processes ◽

Mathematical Simulations ◽

Predictive Role ◽

Sensorimotor Interactions ◽

Forward Projection ◽

Cortical Regions

Abstract Action and Perception are closely linked in many behaviors necessitating a close coordination between sensory and motor neural processes so as to achieve a well-integrated smoothly evolving task performance. To investigate the detailed nature of these sensorimotor interactions, and their role in learning and executing the skilled motor task of speaking, we analyzed ECoG recordings of responses in the high-γ band (70 Hz-150 Hz) in human subjects while they listened to, spoke, or silently articulated speech. We found elaborate spectrotemporally-modulated neural activity projecting in both forward (motor-to-sensory) and inverse directions between the higher-auditory and motor cortical regions engaged during speaking. Furthermore, mathematical simulations demonstrate a key role for the forward projection in learning to control the vocal tract, beyond its commonly-postulated predictive role during execution. These results therefore offer a broader view of the functional role of the ubiquitous forward projection as an important ingredient in learning, rather than just control, of skilled sensorimotor tasks.

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