Population organization of wild pig-tailed macaques (Macaca nemestrina nemestrina) in West Sumatra

A field study on wild pig-tailed macaques was conducted in West Sumatra, Indonesia, during three periods from January 1985 to February 1987. During the nine months of the first two periods, unprovisioned monkeys were traced and observed. During the eight months of the last period, monkeys were provisioned and observed mainly at baiting sites. Three troops and ten solitary males appeared at the two baiting sites. Some males immigrated into and emigrated from the troops. The troops had a multi-male multi-female composition. The size of the various troops was 74, 49, and 81 individuals, respectively, and the mean adult sex ratio in the troops was 1:6.3; that is, markedly biased towards females. The home ranges of two of the troops overlapped considerably. When the troops encountered each other at the baiting sites, a clear dominance relationship was recognized. The troops differed in their integration as ranging units: two of the troops did not form subgroups (temporary fission and fusion of each troop), while the other troop frequently split into subgroups. Recent field studies on pig-tailed macaques have suggested a multi-leveled society with harem-type unit groups. However, in the present study, the troops observed had neither a substructure similar to harem-type groups nor a superstructure that emerged as a result of fusion of the troops. The unit group of the pig-tailed macaques appears to be a multi-male, matrilineal group.     

Maintenance of high-density lipoprotein blood levels prior to spontaneous abortion in pig-tailed macaques (Macaca nemestrina)

Blood was drawn throughout the first half of the pregnancies of 24 pig-tailed macaques (Macaca nemestrina) to evaluate longitudinal high-density lipoprotein (HDL) changes. In all 15 normal pregnancies, HDL decreased at least 50%; the mean value for the group fell from 0.45 gm/liter to 0.17 gm/liter. HDL began to fall after about four weeks of pregnancy. However, no comparable HDL change occurred in nine pregnancies that terminated in spontaneous abortions. This lack of an HDL decrease was unexpected. Subsequent studies showed that the predominant decrease was in the HDL₂ subfraction. The data indicate that the normal physiologic metabolism or utilization of HDL is aberrant early in pregnancies ending in spontaneous abortions and may be due to a dysfunctional fetal-placental unit.     

Blood groups of pig-tailed macaques (Macaca nemestrina).

The human-type A-B-O blood groups of 57 pig-tailed macaques (Macaca nemestrina) were determined and the calculated gene frequencies, O = 0.8908, A = 0.0825 and B = 0.0267, gave excellent fit with the hypothesis of inheritance by triple allelic genes. In tests for simian-type blood groups with rhesus, baboon and crab-eating macaque immune antisera, it was shown that the red cells of pig-tailed macaques are polymorphic for several simian-type specificities defined by those cross-reacting sera. Pig-tailed macaques share with other macaque species the complex Drh-graded blood group system, which seems to occupy a special role among red cell antigens of macaques. Normal sera of three female macaques contained spontaneous isoagglutinins which selectively agglutinated the red cells of some pig-tailed as well as stump-tailed macaques.     

Dominance competition through affiliation and support in Japanese macaques: An experimental study

It has been proposed that monkeys direct grooming to high-ranking individuals in an attempt to obtain agonistic support in return. But whether these two categories of interactions are causally related has proven difficult to establish. Part of the problem stems from the fact that in stable groups social relationships reflect an equilibrium state and that behaviors need only be performed at low rates and long intervals to maintain the current social structure. In theory, however, if affiliative and supportive interactions are indeed causally related, it should be possible to accentuate their temporal relation, hence their causal dynamics. For example, destabilizing dominance relations can be expected to induce competition for status and force individuals to deploy behavioral tactics for settling new rank relations. We experimentally induced rank reversals in a captive group of Japanese macaques (Macaca fuscata) composed of three matrilines (A-B-C rank order). A reversed C-A-B order composed of three individuals per matriline was maintained for 2 weeks. The results show the close temporal relation among (i) asserting one’s rank, (ii) competing for access to dominants through affiliation and interferences in affiliation, (iii) receiving support from dominants against lower-ranking individuals, and (iv) supporting dominants against subordinates. These findings are compatible with one version of the affiliation-for-support hypothesis, namely that monkeys affiliate with dominants as a way to assert their position in the hierarchy. In a functional perspective, mutual selfishness provides a better explanation than reciprocal altruism because the possibility that both groomers and supporters derive immediate net benefits cannot be excluded.     

Influence of dominance rank and affiliation relationships on selfdirected behavior in female Tibetan macaques (Macaca thibetana)

Self-directed behavior(SDB) is characterized as an indicator of anxiety, frustration and stress in nonhuman primates. In this study, we collected self-directed behavior data from one group of free-ranging Tibetan macaques(Macaca thibetana) at Mt. Huangshan, China(September 2012–May 2013) using a combination of behavioral sampling methods including focal animal sampling, behavioral sampling, continuous sampling and instantaneous sampling. Our results showed that females engaged in significantly higher rates of self-directed behavior when they were in proximity to dominant individuals compared to subordinate ones. Conflict losers significantly increased their SDB rates after agonistic episodes, indicating that SDB might also serve as an index of anxiety in M. thibetana. We further found that females significantly increased their SDB rates when focal individual was proximity to weakly affiliation relationship higher rank members than to strongly affiliation relationship higher rank members. If conflicts were not reconciled, the postconflict SDB rates of losers were higher when they stayed with strongly affiliation opponents; if conflicts were reconciled, victims of strongly affiliation relationships opponents engaged in more SDB rates before reconciliation than after reconciliation, while victims of moderately affiliation relationships opponents did not engaged in more SDB rates before reconciliation than after reconciliation. We conclude that both of dominance rank and affiliation relationships might both influence the SDB rates of female Tibetan macaques significantly, suggesting that SDB is not only an index of anxiety in Tibetan macaques, but also can provide a new insight into evaluation of social relationships between individuals.     

Postconflict affiliative contacts between former opponents among wild moor macaques (Macaca maurus)

Agonistic interactions and postconflict behavior of moor macaques (Macaca maurus) were studied in their natural habitat, South Sulawesi, Indonesia. Individuals were involved in 0.28 agonistic interactions per hour. Forty-two percent of agonistic interactions were followed by affiliative contacts between the former opponents. Such affiliative contacts occurred within 2 minutes of the agonistic interaction and were most often initiated by the victim's approach to the aggressor. The most common postconflict behavior was grooming of the aggressor by the victim. The present study provides further evidence of a positive correlation between a high tendency for postconflict affiliative contact and a relaxed dominance style. Captivity might not alter the expression of postconflict behavior. The present study suggests that it is possible to demonstrate the occurrence of reconciliation a posteriori by using data obtained by general focal observation protocols. © 1996 Wiley-Liss, Inc.     

Dyadic and triadic reconciliation in pigtail macaques (Macaca nemestrina)

The tendency in primates for former antagonists to approach and affiliate following aggression has been termed reconciliation because the response is thought to resolve social conflicts produced by aggression. In primate societies, however, an aggressive interaction between two individuals often spreads to include other group members, especially the kin of the combatants. If post conflict affiliation resolves aggressive conflicts in a group, then affiliative increases might occur between combatants and the kin of their opponents following aggression as well as between former opponents. This hypothesis was tested in a captive group of 39 pigtail macaques (Macaca nemestrina) by comparing affiliative response frequencies of combatants during the 5 minute period following aggression to affiliative response frequencies during 5 minute baseline periods not preceded by aggressive activity. Following aggression, affiliation rates increased between combatants and their opponents, aggressors and the kin of their opponents, and aggressors and their own kin. Additional analyses showed that aggression among kin was reconciled more often than aggression among nonkin. Recipients of aggression reconciled with their attackers more often than aggressors reconciled with their victims. Animals with similar dominance ranks reconciled proportionately more often than those with large rank disparities and aggressive infractions of a calculated dominance hierarchy were reconciled more often than attacks consistent with the hierarchy. Results suggest that both dyadic and triadic reconciliations occur in M. nemestrina and that compared to other primate species M. nemestrina exhibit a moderate-to-high conciliatory tendency.     

Viral persistence of simian type D retrovirus (SRV-2/W) in naturally infected pigtailed macaques (Macaca nemestrina)

To elucidate sites of SRV-2/W persistence, tissue DNA from three groups of naturally infected Macaca nemestrina was analyzed for provirus: vertically transmitted, viremic, seronegative macaques; horizontally transmitted, viremic, seronegative macaques, and nonviremic seropositive macaques. In viremic animals infected vertically, provirus was found in many tissues, whereas in those infected horizontally, proviral DNA was limited. In V–Ab+ macaques, provirus was detected in bone marrow and/or ileocecal junction, confirming the presence of provirus in V –Ab+ animals.     

Response to social challenge in young bonnet (Macaca radiata) and pigtail (Macaca nemestrina) macaques is related to early maternal experiences

Previous experience affects how young primates respond to challenging social situations. The present retrospective study looked at one aspect of early experience, the quality of the mother-infant relationship, to determine its relationship to young bonnet and pigtail macaques' responses to two social challenges: temporary maternal separation at 5-6 months and permanent transfer to an unfamiliar peer group at 16-17 months. Relationship quality was measured quantitatively on 30 macaque mother-infant pairs with the Relationship Quality Index (RQI), the ratio of relative affiliation to relative agonism as previously applied to capuchin monkeys. Infants with high RQI values had amicable mother-infant relationships and infants with low RQI values had agonistic mother-infant relationships. Young monkeys with amicable and agonistic relationships showed consistent differences in behavior before, during, and after each social challenge, supporting the hypothesis that juveniles from amicable mother-infant relationships based on the RQI coped more effectively with social challenges than did juveniles from agonistic mother-infant relationships. Results suggest 1) characteristic amicability or agonism in early mother-offspring macaque relationships has the potential to influence offspring behavior in tense social contexts and 2) the RQI is useful as one of a coordinated suite of methods for studying the development of social skills.     

Patterns of affiliation among immature rhesus monkeys (Macaca mulatta)

The affiliative interaction patterns of the immature members of a group of rhesus monkeys at the Yerkes Regional Primate Research Center reflected a strong bias toward matrilineal kin, although this effect was modified by age and sex variables. Association with kin decreased with age, particularly for males. Juvenile males showed less of a kin bias in their behavior than did juvenile females, especially for grooming. Juvenile males also exhibited a preference for interaction with other males. The diminished association with kin and the same-sex bias may be reinforced in adolescence as adult males begin to aggressively target adolescent males involved in agonistic encounters with females or immatures. Adolescent males did not decrease their levels of social interaction relative to those of adolescent females; however, these males preferentially associated with other males (predominantly their own age-sex class) and specifically avoided females and younger animals, both kin and nonkin. Avoidance may diminish conflicts with females or immatures which could result from association, thereby decreasing the potential for selective aggressive interference by adult males. Juvenile and adolescent females maintained strong ties with their kin and preferentially associated with other females and immatures. The breadth of interaction of females with other females may facilitate the establishment of dominance relationships as females mature. Familiarity and predictability may also decrease the necessity of more severe agonistic interaction.     

Sexual behavior of wild Barbary macaque males (Macaca sylvanus)

Recent assertions that the Barbary macaque (Macaca sylvanus) is a multiple-or serial-mounting species are incorrect. Data are presented from over 300 copulations observed among wild Moroccan Barbary macaques which establish empirically that males of this macaque species are single mounters. The average length of an ejaculatory copulation was 8.7 sec, with a range of 6 to 14 sec. Ejaculation occurred an average of 6.3 sec after mounting, with an average of nine pelvic thrusts per ejaculation. Males appeared capable of ejaculating twice within 16 min, and three consecutive times within 37 min. Characteristically, only one mount and ejaculation occurred during a sexual association between an estrous female and each of her consorting males. Schemes of macaque evolution which incorrectly classify Barbary macaques as a multiple-mounting species should be viewed cautiously.     

Dominance in assamese macaques (Macaca assamensis)

A field study of 64 assamese macaques (Macaca assamensis) was conducted at a temple site in Assam, India. Focal and all occurrence scan techniques were used to collect data on agonistic, grooming, and sexual behavior. More than 1,000 hr of data were summarized into agonistic dominance, grooming, and mounting matrices. Rank hierarchies were constructed for all three and compared. We also directly compared each cell in each matrix with the corresponding cells in the other matrices. A nearly linear agonistic dominance hierarchy was found, but it did not correlate with the directionality of mounting or grooming. Adult males mounted females, generally were dominant to females and groomed females more often than they were groomed by females. Younger males groomed older males and were also generally subordinate to older males. These age and sex effects produced some inter‐correlations among grooming, mounting, and dominance but only for specific age‐sex classes. Theoretical models of social exchange were not considered useful in predicting the complex patterns of grooming, mounting, and dominance seen in the present group. Whereas such models may "explain" existing data for some groups and have gained widespread acceptance, they must be empirically tested. Am. J. Primatol. 48:283–289, 1999. © 1999 Wiley‐Liss, Inc.     

Dynamics of fission in a wild Barbary macaque group (Macaca sylvanus)

We studied the dynamics of a group of Barbary macaques (Macaca sylvanus) in Algeria from March 1983 to November 1989. Troop fission began in autumn 1987, when group size had more than doubled, to include 76 animals. We observed 11 temporary splits of this group during the mating seasons of 1987 and 1988. The process was interrupted during the 1988 birth season. In June 1989, fission resumed and ended with the formation of three independent groups that included 50, 24, and 13 individuals. Adult females played an important role in the process of fission. They initiated the rapid formation of two, and later three, coherent nuclei, distributed in two or three bisexual subgroups; on several occasions these nuclei also formed subgroups without any adult males. Adult males remained together in a single nucleus for longer periods of time than females did. However, during fission, 35% (N=20) of resident males emigrated to neighboring groups, while 11 strange males immigrated into the focal group; over 6 years, 57% of the male transfers occurred after the beginning of the process. After group fission, maternally related individuals lived together in the new groups. The majority of resident males remained with the largest of the three groups, while most of the immigrant males were in another group. The third group included a single adult male. Possible factors that induce group fission are discussed.     

Reproductive seasonality in wild northern pig-tailed macaques (Macaca leonina)

Primates - Macaque reproductive patterns range from strictly seasonal breeding to non-seasonal breeding, but factors explaining this variation are not fully understood. Valid reproductive...     

The influence of rank on affect perception by pigtailed macaques (Macaca nemestrina)

Previous studies of affect perception in nonhuman primates have involved young animals and/or manipulations of early experience. Based upon data suggesting that middle-ranked monkeys in small social groups show patterns of behavior different from their low- or high-ranked counterparts, the current study examined the role of social rank in affect perception by normally reared, adult female pigtailed macaques. Employing color videotapes as the presentation medium, we observed animals as they watched unfamiliar animals display social (aggressive or submissive) or nonsocial behavior. Virtually all threats were recorded as the subjects watched the submissive presentations, and most submissive signals occurred while watching aggressive behavior tapes. Middle-ranked monkeys were most attentive during all presentations, and levels of disturbance behavior were related to rank of the watcher and type of presentation observed. The results suggest that dominance status is an influence in the process of affect perception.     

Male dominance rank and offspring-initiated affiliative behaviors were not predictors of paternity in a captive group of pigtail macaques (Macaca nemestrina)

Paternity of 16 pigtail macaque offspring was determined using a DNA profile analysis and was based on two independent assays of the genome of each individual using multilocus DNA probes. The offspring were members of a group of 59 pigtail macaques, including 5 adult males, 1 subadult male, and 37 adult and subadult females. Rank was unrelated to paternity as the first ranking male sired 0, the second ranking male sired 3; the third ranking male sired 0, the fourth ranking male sired 8, and the fifth ranking male sired 2 offspring. The subadult male sired 0 offspring. The DNA analysis was effective in excluding possible sires of 3 offspring whose mothers had become pregnant by another male before being introduced to the study males. Subsequent semen evaluation revealed an absence of sperm in the semen of the alpha male, but revealed a sperm count within normal limits in the third ranking male, who also sired no offspring. Behavioral data focusing on male-offspring interactions found that offspring did not preferentially affiliate with their sire and that males did not affiliate with their offspring frequently enough for analysis. Thus, this study of one captive pigtail macaque group demonstrates that: (1) rank was not a predictor of reproductive success; and (2) there was no preferential attraction for one's own offspring by males or one's own sire by offspring.     

Sires influence fetal death in pigtailed macaques (Macaca nemestrina)

Computerized colony records were used to identify dams and sires whose reproductive histories while breeding in harem groups indicated high or low risk for producing fetal deaths. The monkeys were then singly caged and bred within and between risk conditions during 24- to 72-hour matings. Although the low- and high-risk sires did not differ in ability to achieve conceptions, the results revealed that reproductive history predicted subsequent fetal death rates, and sires made a substantial contribution. Overall, high-risk sires had a 4.86 times higher relative risk of producing fetal death than low-risk sires. Compared with this figure, high-risk dams had only a 2.64 times higher risk for fetal death than low-risk dams. The male effect was most evident in comparisons of between- and within-risk matings. Females with excellent reproductive histories experienced a threefold increase in fetal deaths when mated with high-risk males, whereas females with poor reproductive histories experienced almost a 50% reduction in fetal deaths when mated with low-risk males. The results show that male factors beyond fertility need to be considered when examining the causes of reproductive failure in captive primates.     

Analysis of immunoglobulin,complements and CRP levels in serum of captive northern pig-tailed macaques (Macaca leonina)

The northern pig-tailed macaque(NPM,Macaca leonina) has become a widely used animal model in biomedical research. In this study, we measured serum immunoglobulin IgG, IgM, IgA, complement C3, C4 and CRP levels in 3-11 year old captive northern pig-tailed macaques using HITACHI 7600-20 automated chemistry analyzer in order to determine the influences of age and gender on these items. The results showed that serum IgA, IgM, C3 and C4 levels were not correlated with age(P0.05), while serum IgG levels increased progressively with age(r=0.202;P=0.045). Serum IgG, IgA, IgM and C3 levels were higher in females than in males(P0.05). Moreover, serum C3 concentration was both positively and strongly correlated with that of C4(r=0.700; P0.0001). This study provides basic serum immunoglobulin and complement data of captive northern pig-tailed macaques, which may prove useful for future breeding efforts and biomedical research.     

Positional behavior of long-tailed macaques (Macaca fascicularis) in northern Sumatra

Although the majority of extant primates are described as "quadrupedal," there is little information available from natural habitats on the locomotor and postural behavior of arboreal primate quadrupeds that are not specialized for leaping. To clarify varieties of quadrupedal movement, a quantitative field study of the positional behavior of a highly arboreal cercopithecine, Macaca fascicularis, was conducted in northern Sumatra. At least 70% of locomotion in travel, foraging, and feeding was movement along continuous substrates by quadrupedalism and vertical climbing. Another 14-25% of locomotion was across substrates by pronograde clambering and vertical clambering. The highest frequency of clambering occurred in foraging for insects, and on the average smaller substrates were used in clambering than during quadrupedal movement. All postural behavior during foraging and feeding was above-substrate, largely sitting. Locomotion across substrates requires grasping branches of diverse orientations, sometimes displaced away from the animal's body. The relatively low frequency of across-substrate locomotion appears consistent with published analyses of cercopithecoid postcranial morphology, indicating specialization for stability of limb joints and use of limbs in parasagittal movements, but confirmation of this association awaits interspecific comparisons that make the distinction between along- and across-substrate forms of locomotion. It is suggested that pronograde clambering as defined in this study was likely a positional mode of considerable importance in the repertoire of Proconsul africanus and is a plausible early stage in the evolution of later hominoid morphology and locomotor behavior.