bluuebunny/crossref_metadata_2025 huggingface dataset:
Vocal behavior of captive Sichuan golden monkeys (Rhinopithecus r. roxellana)
Authors: Tenaza R. R. , Fitch H. M. , Lindburg D. G.
Published: June 2005

Vocal behavior of four pairs of adult Sichuan golden monkeys was studied at the San Diego, Seattle, Los Angeles, and San Francisco zoos between November 1984 and October 1986. Four call types made up 86% (1,357/ 1,578) of vocalizations that occurred during 45 h of tape‐recording. All four major vocalization types were made by both sexes. There was, however, significant sexual asymmetry in their production: 82% to 99% of each type was produced by one sex or the other. Frequently, duets developed when an individual male or female responded to the vocalizations of its cagemate. Males vocalized more than did females in each of the four pairs, and males responded vocally to female calls more than twice as frequently.
Diet of the northern bearded saki (Chiropotes satanas chiropotes): A neotropical seed predator
Authors: Van Roosmalen Marc G. M. , Mittermeier Russell A. , Fleagle John G.
Published: June 2005

Data on the diet of Chiropotes satanas chiropotes, the northern bearded saki, has been collected during several years of primate field observations in the Raleighvallen‐Voltzberg Reserve in Suriname. This species feeds predominantly on immature seeds and ripe fruit, mainly the former. Chiropotes is especially fond of the members of the Brazil nut family, Lecythidaceae, and other species with exceptionally hard or tough seed pods. Concomitantly, Chiropotes shows striking dental and gnathic adaptations that facilitate opening and ingesting these well‐protected food items. Seed predation in the Old World colobine, Colobus satanas, has been discussed primarily as a strategy for survival in forests characterized by leaves with low nutrient content and high toxicity; however, it now appears that arboreal seed predation is a relatively widespread primate dietary strategy found among higher primate species in a variety of forest types on three continents. It is yet another way of “making a living” in a tropical rain forest.
Enzootic hepatitis A infection in cynomolgus monkeys (Macaca fascicularis)
Authors: Slighter R. G. , Kimball J. P. , Barbolt T. A. , Sherer A. D. , Drobeck H. P.
Published: June 2005

During a toxicology study in cynomolgus (long‐tailed or crab‐eating) monkeys (Macaca fascicularis), a randomly distributed incidence of significantly increased hepatic enzyme activity was observed. Premedication hepatic enzyme activity in all monkeys of this study was normal, but increased alanine aminotransferase (ALT) activity was found in 4 of the 24 animals 2 weeks after initiation of the study and in 10 of 24 at 4 weeks. A drug‐related effect was considered unlikely initially because the increases were not doserelated, and a 3‐year review of 655 cynomolgus monkeys revealed a 15–20% incidence of increased hepatic enzyme activity. Good correlation was subsequently established between increased hepatic enzyme activity, active hepatitis A virus (HAV) infection, and histomorphologic confirmation of hepatitis (chronic periportal inflammation). Follow‐up viral serodiagnostic screening of resident macaques revealed an overall incidence of anti‐HAV IgG in 80% (155/193) of cynomolgus and in 70% (14/20) of rhesus monkeys. Serial screening demonstrated that several initially negative monkeys became seropositive for anti‐HAV IgG, and a few acquired active infection (anti‐HAV IgM). Among newly acquired cynomolgus monkeys, 2.5% (2/80) had an acute HAV infection, and 35% (28/80) eventually tested positive for anti‐HAV IgG while quarantined in the primate facility. The characterization of an enzootic HAV infection in incoming monkeys posed a significant risk for the primate colony and handlers. Rigorous sanitation, isolation, and quarantine procedures, including personnel training and additional protective clothing for personnel working in the primate colony, reduced tho potential for transmission and arrested the outbreak. Experimenters should be cautious in ascribing toxicity to a test article based solely on increased hepatic enzyme activity associated with chronic periportal inflammation.
Glucose disappearance rate in rhesus monkeys: Some technical considerations
Authors: Jen K‐L. C. , Hansen B. C.
Published: June 2005

The intravenous glucose tolerance test (IVGTT) has been widely used as a tool to assist in the diagnosis of diabetes mellitus. Glucose disappearance rate (KG) is calculated as an indicator of relative glucose tolerance; however, a standardized dose, consistent sampling times, and a consistent formula for the calculation of KG have not yet been established for rhesus monkeys. Interpretation of results reported by different laboratories has, therefore, been rendered difficult. In the present study, 48 IVGTTs obtained from 33 male rhesus monkeys ranging widely in glucose tolerance have been analyzed. Various formulas for calculating KG values have been tested in all experiments including a range of different pairs of time points, as well as the t1/2. Regression analysis revealed that the loge transformation of the plasma glucose levels obtained after an intravenous glucose load were best fitted with a straight line during the period between five and 20 minutes (R2 = 0.97 ± 0.005). The use of time points prior to the five‐minute value tended to produce spuriously larger KG values, while sampling points that were later than 30 min occasionally produced an invalid KG because in some monkeys the plasma glucose levels had already returned to basal levels. The advantages of using the five‐ and 20‐minute glucose levels in calculating the KG include (1) the optimal reflection of tissue uptake of glucose; (2) the relatively short sampling time required to obtain an accurate, consistent, and meaningful value for KG; and (3) the relative ease in the calculation of KG.
Preliminary observations on squirrel monkey (Saimiri oerstedi) vocalizations in Costa Rica
Authors: Boinski S. , Newman J. D.
Published: June 2005

This study was an initial attempt to analyze quantitatively vocalizations from the Central American squirrel monkey, Saimiri oerstedi. Vocalizations were recorded in the wild at P. N. Corcovado (S. o. oerstedi). and at P. N. Manuel Antonio (S. o. citrinellus). Additional recordings were made from captive individuals of both subspecies. The acoustic structure of analyzed vocalizations resembled most closely the vocal repertoire of South American Saimiri with the “gothic arch” phenotype, in agreement with the prominent gothic arch facial pattern of S. oerstedi. New structural subtypes of the twitter (“dog‐tooth twitter”) and the chuck (“bent‐mast chuck”) not previously found in an extensive library of South American Saimiri sound spectrograms were documented. Calls used by older infants when socially separated and when approaching an adult male were essentially identical (sharing typical “isolation peep” structural features) but had significantly different duration and peak frequency. Analysis of recordings from an escaped captive female calling outside her compound over a 3‐day period indicated the presence of numerous structural intermediates between typical chuck, twitter, and peep calls.
Leptospiral agglutinins in the Cayo Santiago macaques
Authors: Kessler Matt J. , Everard C. O. R.
Published: June 2005

The colony of free‐ranging rhesus monkeys (Macaca mulatta) on Cayo Santiago, Puerto Rico, was surveyed for leptospiral agglutinins. Only 5 (3%) of 169 monkeys (25% of the population) were seropositive (titers of ⩾ 1:100). An additional 29 animals (17%) had titers ⩽1:50. The proportions of seropositive males and females were 22% and 18%, respectively, and twice as many adult as immature animals (32% vs. 15%) were positive. In most seropositive monkeys a single serogroup predominated, Icterohaemorrhagiae being recorded in nearly 60% of these animals. In a follow‐up survey conducted a year later, 4% of 158 of the original monkeys were seropositive, with titers of from 1:100 to 1:200. None of 22 Rattus rattus captured on Cayo Santiago had agglutinins to pathogenic serovars. Despite contact with rats and ingestion of stagnant water, the serological evidence, the excellent clinical condition, low mortality, and high reproductive rates of the Cayo Santiago macaques indicate that leptospirosis is not a health problem in this free ranging monkey colony.
Population densities and geographic distribution of night monkeys (Aotus nancymai and Aotus vociferans) (cebidae: Primates) in Northeastern Peru
Authors: Aquino Rolando , Encarnación Filomeno
Published: June 2005

Population densities of two species of night (or owl) monkeys (Aotus nancymai and Aotus vociferans) were estimated using transect census methods. Densities of Aotus nancymai were approximately 46.3 individuals/km2 in lowland forests and 24.2 individuals/km2 in highland forests. For Aotus vociferans densities were 33.0 individuals/km2 in lowland forests and 7.9 individuals/km2 in highland forests. A. vociferans occurs north of the Río Amazonas‐Marañon and A. nancymai south of it, except for the northern enclave between the Ríos Tigre and Pastaza. The two species are nowhere sympatric. However, the two known karyotypic forms of A. vociferans occupy the same habitats throughout the Peruvian range of the species.
Intergroup interactions in wild Barbary macaques (Macaca sylvanus), Ghomaran Rif mountains, Morocco
Authors: Mehlman P. T. , Parkhill R. S.
Published: June 2005

Data are presented on intergroup interactions between six groups of Macaca sylvanus in the Ghomaran region of the Moroccan Rif mountains. Intergroup encounters (0.026/observation hour) were defined as two groups being near each other (< 150 m). Encounters were further classified into: 1) neutral (indeterminate) encounters, in which very little intergroup interaction took place, with the exception of male monitoring (N = 7); 2) approach‐retreat encounters with intergroup displacement, in which, without any overt agonism, members of one group slowly approached another and caused it to retreat (N = 3); and 3) agonistic encounters with intergroup displacement (N = 3). These results are compared to the only other study of intergroup interactions in wild Barbary macaques, and it is concluded that 1) observations of intergroup unification and/or coordination of movement in Barbary macaques (“herding”) probably resulted from observer error, or if these phenomena do occur, they are rare throughout the range of this species; 2) approximately half of all intergroup encounters in both studies resulted in intergroup displacement and/or intergroup agonism, evidence of intergroup competition; and 3) current data on intergroup interactions in Barbary macaques conform to the predictions of Wrangham's model of mutually competitive female‐bonded, multimale groups.
Demography, ranging patterns, and activity budgets of black spider monkeys (Ateles paniscus chamek) in the Manu National Park, Peru
Authors: Symington M. McFarland
Published: June 2005

Results of a long‐term field study on the ecology and social organization of two groups of black spider monkeys (Ateles paniscus chamek) in Peru are reported. Demography, ranging patterns, and activity budgets provide insight into some of the proximate determinants of fission‐fusion social organization in this species and illustrate the different strategies used by males and females to gain access to critical resources. Longitudinal data on known individuals provide evidence for male natal philopatry and female emigration at sexual maturity in this population. Interbirth intervals are long (mean = 34.5 months) in comparison with most other primate species, and 5 of 15 infants seen within a few days of birth died or disappeared before they were a year old. Home ranges are large (150–250 ha) and fairly discrete; overlap with neighboring groups is on the order of 10–15%. Males and females differed substantially in their ranging patterns; females, particularly those with infants, restricted much of their ranging to a “core area” 20–33% the size of the total group range, whereas males ranged more evenly over the entire area occupied by the group. Daily path length varied over almost an order of magnitude from 465 m to 4,070 m, with a mean of 1977 m. Males spent more time traveling and less time feeding than most females. These results are compared with those obtained in previous studies of Ateles and with similar data from other primate species to assess their implications for the evolution of fission‐fusion sociality in spider monkeys. The ecological factors responsible for the evolution of very similar social organizations in spider monkeys and chimpanzees are discussed.
Effect of tetanus toxoid inoculation on mortality in the Cayo Santiago macaque population
Authors: Kessler Matt J. , Berard John D. , Rawlins Richard G.
Published: June 2005

Tetanus was a major cause of mortality in the free‐ranging population of rhesus monkeys (Macaca mulatta) on Cayo Santiago. From 1977 to 1984 the mean (±1 SD) annual total mortality rate (excluding neonatal deaths within 48 h postpartum, abortions, and stillbirths) was 6.39% ± .94%, and the mean annual tetanus mortality rate was 1.33% ± .45%. Tetanus deaths accounted for 19.5% of the total mortality in the colony. In 1985, all monkeys on the island, except infants and six adult monkeys, were given primary inoculations of tetanus toxoid. The following year, boosters were administered, and yearlings received primary inoculations. One fatal case of tetanus and one recovery from mild disease occurred in uninoculated adult monkeys in 1985, but no additional cases have been observed since. For 1985–1986 the mean annual total mortality rate was 3.69% ± .05%, and the mean annual tetanus mortality rate was .08% ± .08%. Thus, during the 2 years after inoculation against tetanus, the mean annual total mortality rate and the mean annual tetanus mortality rate declined by 42.2% and 94.0%, respectively, when compared to the 8‐year period (1977–1984) prior to inoculation. These differences were significant [(χ2 = 12.48; P < .005), (χ2 = 16.94; P < .005)]. The elimination of tetanus infections through mass inoculation of the Cayo Santiago colony is expected to have a profound impact on the demography of the population by increasing the rate of population growth, by decreasing the differential rates of increase of the component social groups, and by changing the age distribution of the population.
Age estimation in rhesus macaques (Macaca mulatta) based on mandibular dimensions
Authors: Bouvier Marianne
Published: June 2005

A new technique has been developed for estimating age in rhesus macaques (Macaca mulatta) that is based on mandibular measurements and has several advantages over presently available techniques. First, the new technique is relatively quick and inexpensive because a single measurement or radiograph suffices to produce an age estimate. Second, mandibular growth represents a more continuous phenomenon than either epiphyseal union or dental eruption; therefore, age estimates may be made throughout the period of growth without significant gaps in the process. Finally, the new technique may be used on incomplete or even fragmentary skeletal material because it requires that only a portion of the mandible be preserved. The new technique produces age estimates with a prediction error of ±5.08 months in males and ±7.29 months in females. These errors are only slightly higher than those found previously for dental eruption or epiphyseal union data.
Environmental influences on mountain gorilla time budgets
Authors: Watts David P.
Published: June 2005

Data on the time budgets of mountain gorillas (Gorilla gorilla beringei) were collected during field studies in the Virunga Volcanoes region of Rwanda and Zaire. Focal sampling was used to determine the proportion of time that individuals of different age/sex classes spent in several mutually exclusive activity states. The gorillas spent the majority of daylight hours feeding; most of the rest of the day was devoted to resting, with little time spent moving or engaged in social activity. The time budget varied among the different subhabitats used by the gorillas, and the gorillas satisfied subsistence needs more quickly when in areas where food was more abundant and/or of better nutritional quality. Silverbacks spent more time feeding than all other age/sex classes, but age/sex class differences were not great. All age/sex classes responded to variability in habitat quality in similar fashion. Unlike the case for many other primates, there was no significant seasonal variation in time budgets. There was a direct relationship between group size and time spent feeding, although variation in relation to group size was lower than that in relation to variation in habitat quality. These results are consistent with the relationship of feeding time to body size in primates. They are also consistent, with other evidence that social foraging entails a cost to gorilla females, but that this cost is low in comparison to those faced by many other primates. Permanent association with males apparently offers little ecological disadvantage to females, who are likely to be more than compensated by mutualistic benefits.
New material of Qatrania from Egypt with comments on the phylogenetic position of the parapithecidae (primates, Anthropoidea)
Authors: Simons E. L. , Kay R. F.
Published: June 2005

New material of the early anthropoid primate Qatrania wingi and a new species of that genus are described. Several features of the dental anatomy show that Qatrania, while quite primitive relative to other anthropoids in many ways, is most likely a parapithecid primate. The new material suggests that several dental features previously thought to ally parapithecids with the catarrhine primates were actually evolved in parallel in catarrhines and some parapithecids. Furthermore, all nonparapithecid anthropoids (including platyrrhines and catarrhines) share a suite of derived dental and postcranial features not found in parapithecids. Therefore, parapithecid origins may predate the platyrrhine/catarrhine split.
Responsiveness to objects in two social groups of tufted capuchin monkeys (Cebus apella)
Authors: Visalberghi Elisabetta
Published: June 2005

The responses of two social groups of Cebus apella to novel or familiar objects were examined, both in scarce and in abundant conditions. The aim was to obtain a description of capuchins' general norms of behavior toward objects, focusing on the variability across sex/age classes. Plain wooden blocks were presented to each group of monkeys in four phases. In phase I, the blocks were scarce and novel; in the following phases the blocks were abundant and increasingly more familiar. Several categories of behaviors directed toward the blocks were scored. The blocks elicited high levels of responsiveness throughout the experiment. In both sexes, responsiveness tended to decrease across phases. In all phases, males interacted with the blocks more than did females. Age was a significant determinant of responsiveness. Furthermore, age‐classes showed different trends in level of responsiveness across phases. Sex and age significantly affected the behavioral pattern of interaction with the blocks. Dominance did not seem to constrain monkeys' responsiveness. The high and sustained responsiveness toward objects by Cebus apella is consistent with their manipulative skills and their varied habitat exploitation.
Food‐reinforced yawning in Macaca tonkeana
Authors: Anderson James R. , Wunderlich Daniel
Published: June 2005

An operant conditioning paradigm comprising continuous food‐reinforcement, fixed‐ratio responding, and extinction procedures was used to evaluate the possibility that adult male macaques can control their rate of yawning. Two non‐food‐deprived Macaca tonkeana quickly learned to produce yawns for food rewards. They also increased the rate of production according to fixed‐ratio requirements, and showed initial response peaks followed by diminished rates of yawning during extinction. The results indicate that adult male macaques can yawn voluntarily. Further work along these lines may help distinguish among different types of yawning as indicated in the literature.
Macaca thibetana at Mt. Emei, China: III. Group composition
Authors: Zhao Qikun , Deng Ziyun
Published: June 2005

Data on group composition at the end of the 1986 birth season were collected from six groups of Macaca thibetana. All adult males, the members of group A, and some conspicuous animals were recognized individually. Fourhundred survey sessions were completed. The mean group size was 38.3 (SD = 13.8, range: 28–65); the number of adult females was the best correlate of total group size. The mean adult sex ratio (F:M) across groups was 3:1 (SD = 1.9, range: 1.5–6.5:1), which significantly deviated from 1:1. Sex ratios (F:M) in newborns, juveniles, and all members did not significantly deviate from 1. The ratio of immature animals to adults was 1.5 to 1 (average of groups); that is, 60% of the population was composed of immature animals, and the population was growing.
Excrement distribution and habitat use in Rhinopithecus bieti in winter
Authors: Zhao Qikun , He Shunjin , Wu Baoqi , Nash Leanne T.
Published: June 2005

Winter ranging patterns of Rhinopithecus bieti were determined using feces as the ranging trace. The appearance of the feces was unique in the study habitat. The sampled habitats were a well‐forested area and a partly altered one. Analyses of excrement distribution showed: (1) monkeys tended to use the upper part of the forest belt, ranging between 3,900 and 4,100 m above sea level; (2) monkeys came to the ground and used the partly altered habitat, where only some forest remained; (3) the structure of resources had little influence on determining the ranging elevation; and (4) the animals spent more time in the local valley than on the local ridge, probably using the former as a sleeping site.
Aerial maneuvers of leaping lemurs: The physics of whole‐body rotations while airborne
Authors: Dunbar Donald C.
Published: June 2005

Several prosimian species begin a leap from a vertical support with their back toward the landing target. To reorient themselves from this dorsally facing, head‐first lift‐off to a ventrally facing, feet‐first landing, the animals combine an initial twist with a partial backward somersault. Cinefilms of a captive colony of ringtailed lemurs (Lemur catta) revealed that during leaps from vertical poles to horizontal supports, the backward somersaulting rotations were often initiated while the animals were airborne. How could these prosimians initiate rotations in the absence of externally applied forces without violating angular momentum conservation? The problem was approached through vector analysis to demonstrate angular momentum (H) changes about the three principal (symmetrical) axes of rotation for a series of critical body positions that were extracted from the filmed sequences. One L. catta specimen was segmented to provide the dimensions and weights necessary for modeling the various body positions. These data were also used to calculate moments of inertia about the three principal axes in order to predict if rotations about these axes were stable or metastable. Lemurs, like any projectile, must conserve the total angular momentum (HT) established at lift‐off. HT, however, is a vector quantity that is the resultant of component vectors about the three principal axes. Thus, H about the individual axes may change as long as HT remains constant. Strategically timed tail movements tilted the body, thereby changing the H value about the head‐to‐toe (twisting) axis. To conserve HT, also aligned along the twisting axis, angular momentum transferred to the somersaulting axis. Owing to the direction of tail‐throw, the initiated rotations were partial backward somersaults that brought the hindlimbs forward for landing. This strategy for initiating specific rotations parallels that practiced by human springboard divers.
Reproduction in the slow loris (Nycticebus coucang)
Authors: Izard M. Kay , Weisenseel K. A. , Ange R. L.
Published: June 2005

The reproductive biology of the slow loris (Nycticebus coucang) is poorly documented because of infrequent captive breeding success and the absence of field studies of this species. Reproductive data were collected from a breeding colony of slow lorises held at the Duke University Primate Center for the past 10 years. Nineteen infants were born, with a sex ratio of 1:1 and a neonatal mortality rate of 15.8%. In all cases, litter size was one. Females born in the colony copulated for the first time between 18 and 24 months of age. A male that reached sexual maturity in the colony sired his first offspring at the age of 17 months. Estrous cycles ranged in duration from 29–45 days, with copulations usually occurring for 1 day of estrus. Gestation length averaged 192.2 days. Although a postpartum estrus was observed in three cases of infant death, no conceptions resulted. Lactation lasted approximately 6 months. A clear birth peak was observed, with 12 out of 19 births occurring in March, April, and May. The comparatively low basal metabolic rate of this species may account for the unusually low reproductive rate of the slow loris in comparison with other prosimian primates.
Capuchin monkey (Cebus apella) grooms her infant's wound with tools
Authors: Ritchie Bill G. , Fragaszy Dorothy M.
Published: June 2005

After an attack on her 6‐day‐old infant, a capuchin monkey manufactured, modified, and used simple tools to manipulate her infant's head wound, and applied modified plant materials to the wound. The monkey's preparation and use of plant materials were varied and skillful. Several contextual factors probably facilitated the extension of tool‐using behaviors that this female used in treating her own wounds to treating another's wound. We consider these in relation to the prehistorical development of social medicine in our own species.
Vigilance during play in squirrel monkeys
Authors: Biben Maxeen , Symmes David , Bernhards Deborah
Published: June 2005

Play by young squirrel monkeys (Saimiri boliviensis) may put them and other troop members at risk for predation because youngsters are noisy, separated from adults, and not vigilant when at play. In a study using separated groups of adults and 1‐year‐old juveniles caged outdoors, we found that adult female squirrel monkeys become more vigilant during periods of spontaneous play among juveniles. This behavioral response could be obtained with auditory cues (play vocalizations) alone. Five times as much vigilance activity was directed toward an area from which threat or disturbance was likely to come as was directed toward the juveniles themselves. These results suggest both an adaptive, compensatory increase in adult vigilance during play and a function for play vocalizations. Additional functions for play vocalizations remain to be investigated.
Excretion of estrone, estradiol, and progesterone in the urine and feces of the female cotton‐top tamarin (Saguinus oedipus oedipus)
Authors: Ziegler T. E. , Sholl S. A. , Scheffler G. , Haggerty M. A. , Lasley B. L.
Published: June 2005

The excretion of three gonadal steroids was studied in the urine and feces of female cotton‐top tamarins (Saguinus oedipus oedipus). Each steroid, 14C‐estrone, 14C‐estradiol, and 14C‐progesterone, was injected into a separate female cotton‐top tamarin. Urine and feces were collected at 8 hr intervals for 5 days on the three tamarins. Samples were analyzed to determine the proportion of free and conjugated steroids. Steroid excretion patterns were determined by sequential ether extraction, enzyme hydrolysis, and chromatography. Labeled estrone was excreted in a slow and continuous manner into the urine (57%) and feces (43%) with 90% of the steroid conjugated. The nonconjugated form had an elution profile identical to 3H estrone, but the conjugated portion was not completely hydrolyzed by enzyme. Labeled estradiol was excreted primarily in the urine (87%) and was released rapidly. Over 90% of the injected 14C‐estradiol was excreted in urine as a conjugate, of which 41% was converted to an estrone conjugate and the remaining 59% was excreted as a polar estradiol conjugate. Labeled progesterone was excreted primarily in the feces (95%), 61% of which was free steroid. Four to six individual peaks of radioactivity were found when using celite chromatography and high performance liquid chromatography (HPLC), indicating that progesterone is metabolized into several urinary and fecal metabolites. One of these peaks matched 3H‐progesterone and others may be pregnanediols, pregnanetriols, and 17‐hydroxyprogesterone. These steroidal excretion patterns help explain the atypical hormonal patterns seen during the tamarin ovarian cycle.
Morphology and relationships of the orangutan fatty cheek pads
Authors: Winkler Linda A.
Published: June 2005

The present paper examines the anatomical relationships as well as possible developmental and functional relationships of the fatty cheek pad characteristic of the adult male orangutan. The research involves the dissection of 11 orangutans of both sexes in a variety of age categories. All specimens possess either a fat pad or a subcutaneous connective tissue fascial compartment in the lateral face extending superiorly from slightly above the inferior border of the mandible to the temporal region. In immature specimens as well as adult females, fat deposits within the connective tissue compartment are scarce or nonexistent, whereas pubescent male specimens or older possess accumulations of fibro‐fatty tissues in this region. The extensive fat accumulations of the adult male cheek flange are related to age and sex and to modifications in related facial musculature, especially mm. platysma, zygomaticus, orbicularis oculi, and orbitotemporalis and frontalis. These muscles are clearly related to the cheek pad structures in both sexes but appear to assume a supportive role in the males. The cheek pad has no direct bony attachments, but its mass may have a significant effect on facial morphology. The development of the cheek pad is temporally variable and its function remains speculative although the presence of a fully developed flange may be related to behavioral modifications.
Styles of dominance and their endocrine correlates among wild olive baboons (Papio anubis)
Authors: Sapolsky Robert M. , Ray Justina C.
Published: June 2005

We have studied the relationship between dominance rank and physiology among male olive baboons (Papio anubis) living freely in a national park in Africa. In stable hierarchies, dominant males consistently have lower basal concentrations than do subordinates of the adrenal glucocorticoid cortisol. Because of the known catabolic actions of glucocorticoids, dominant males may be less at risk for some of the pathogenic consequences of glucocorticoid overexposure. We find that low basal cortisol concentration is not, in fact, a marker of social dominance; instead, it is only found among dominant males with a certain style of dominance. Lower basal cortisol concentrations occurred among males with any of the following behaviors: the most marked ability to distinguish between threatening and merely neutral interactions with rivals and, if the former, the greatest likelihood of initiating a fight; the most skill at distinguishing between winning and losing a fight and, if the latter, the greatest likelihood of displacing aggression onto a third party. Collectively, these behaviors suggest high degrees of social skillfulness, control, and predictability over social contingencies, all recognized as psychological features that minimize the pathophysiological impact of stress. Dominant males lacking these behavioral features, in contrast, had as high cortisol concentrations as did subordinate males. Finally, low basal cortisol concentrations were also a feature of males with the longest tenures in the dominant cohort, suggesting that this endocrine dichotomy is meaningful in terms of life histories.
Lactation and care for unrelated infants in forest‐living ringtailed Lemurs
Authors: Pereira Michael E. , Izard M. Kay
Published: June 2005

An adult female ringtailed lemur (Lemur catta) known not to have been pregnant showed spontaneous lactation in response to twin infants born to an unrelated female. The females had met only 7 months earlier, when they and two other unrelated adult females were released from separate locations in a forest enclosure to form a new social group. Three months after release, an adult male from an adjacent enclosure gained access to the new group for 1 day, the day of one female's estrus. No males had access to the females throughout the remainder of the breeding season. Within 2 weeks of the birth of the twins, one of the other adult females began carrying the infants frequently, typically one at a time. All three females were checked for lactation when the infants were two months old. Both their mother and the unrelated adult who had been carrying the infants were producing milk. The third adult female, who never carried either infant, had no milk. The third adult female, who never carried either infant, had no milk. This female, however, like the two maternal females, frequently attacked unfamiliar immigrating adult males when the males approached the infants. Potential implications of these observations concerning the social organization of ringtailed lemurs are discussed.
Social relationships of mountain baboons: Leadership and affiliation in a non‐female‐bonded monkey
Authors: Byrne R. W. , Whiten A. , Henzi S. P.
Published: June 2005

Instead of close and differentiated relationship among adult females, the accepted norm for savanna baboons, groups of Drakensberg mountain baboons (Papio ursinus) showed strong affiliation of females towards a single male. The same male was usually the decision‐making animal in controlling group movements. Lactating or pregnant females focused their grooming on this “leader” male, producing a radially patterned sociogram, as in the desert baboon (P. hamadryas); the leader male supported young animals in the group against aggression and protected them against external threats. Unlike typical savanna baboons, these mountain baboons rarely displayed approach‐retreat or triadic interactions, and entirely lacked coalitions among adult females. Both groups studied were reproductively one‐male; male‐female relationships in one were like those in a unit of hamadryas male at his peak, while the other group resembled the unit of an old hamadryas male, who still led the group, with a male follower starting to build up a new unit and already monoplizing mating. In their mountain environment, where the low population density suggests conditions as harsh for baboons as in deserts, adults in these groups kept unusually large distances apart during ranging; kin tended to range apart, and spacing of adults was greatest at the end of the dry, winter season. These facts support the hypothesis that sparse food is responsible for convergence with hamadryas social organization. It is suggested that all baboons, though matrilocal, are better categorized as “cross‐sex‐bonded” than “female bonded”.
Early embryonal culture of the cynomolgus monkey (Macaca fascicularis)
Authors: Fujisaki Masami , Suzuki Michihiro , Kohno Misao , Cho Fumiaki , Honjo Shigeo
Published: June 2005

Ovaries of ten female cynologus monkeys (Macaca fascicularis) were superstimulated with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG). During this treatment, follicular development was monitored by ultrasonography. After three to four injections of PMSG, ovaries began to show an increase in their size. After seven to ten injections of PMSG and a hCG injection, a total of 183 oocytes (18.3±14.1/ animal, mean±SD) were recovered from these females by laparotomy. Five nulliparous females produced 24.2±18.2 oocytes per animal, and the remaining five parous females produced 12.5±5.46 oocytes per animal. In total, 133 (72.6%) of the 183 oocytes were classified morphologically as matured, and 130 of them were inseminated with cynomolgus monkey sperm for 18 hours in vitro. The second polar body was observed in 92 (71%) of the inseminated oocytes, and 54 (59%) of the 92 oocytes showed cleavage division at least once. When these oocytes were fertilized and cultured in serum‐free media, they stopped their development at 4‐cell stage. In contrast to this condition, about a half of fertilized oocytes in serum‐free media were able to develop to morula stage 4 days after insemination by transferring them into serum‐containing media after 2‐cell stage.
Functional aspects of reconciliation among captive long‐tailed macaques (Macaca fascicularis)
Authors: Aureli Filippo , Van Schaik Carel P. , Van Hooff Jan A. R. A. M.
Published: June 2005

After an agonistic conflict between two animals, they may exchange affiliative social contacts. The function of this reconciliation behavior is thought to be the repair of the social relationship between the two opponents. We examined the hypothesis that reconciliation is socially effective because it may also lead to a reduction of the victim's acute stress. Reconciliation was studied in a well‐established captive group of long‐tailed macaques (Macaca fascicularis). The behavior of the victim in a 10 min period after the end of an agonistic interaction was recorded and compared with that of a control observation made on the same animal the next day. The tendency to reconcile was elevated above control levels only during the first 3 min. Reconciliation led to a fast reduction in scratching rates and to a decrease of the reoccurrence of aggression received. Losers took the initiative to reconcile more than expected. Dominants granted reconciliation depending on their relatedness with the victims and on the quality of the relationship with them. After those interactions in which contra‐aggression and no clear submission occurred, the reconciliation rate was remarkably high. These results suggest that reconciliation can be an effective means to reduce the victim's acute stress and that its function in repairing social relationships can partly be mediated by its physiological effects. The intimate relation between the quality of the social relationship and the conciliatory tendency can be extrapolated to explain interspecific variation.
Predation on capped langurs (Presbytis pileata) by cooperatively hunting jackals (Canis aureus)
Authors: Stanford C. B.
Published: June 2005

Predation attempts by cooperatively hunting jackals (Canis aureus) on capped langurs (Presbytis pileata) in moist deciduous forest in north‐central Bangladesh are described. The incidents were observed during a 15‐m field study of the ecology and behavior of capped langurs. Two attacks on langurs were made cooperatively by, in one instance, a pair and in a second instance a small pack of jackals. One of these attacks was successful. Although P. pileata is a highly arboreal species, both attacks took place in rare instances of ground travel by the langurs.
Social rank and sex ratio of captive long‐tailed macaque females (Macaca fascicularis)
Authors: Van Schaik C. P. , Netto W. J. , Van Amerongen A. J. J. , Westland H.
Published: June 2005

Variation in birth sex ratios in primates can be accounted for by two hypotheses: the local resource competition hypothesis [Silk: American Naturalist 121:56–66, 1983] and the hypothesis of Trivers & Willard [Science 179:90–92, 1973] concerning the maternal effect on the quality of a male. We examined the effects of female dominance rank on aspects of reproduction in three well‐established captive groups of long‐tailed macaques (Macaca fascicularis). High‐ranking females produced a higher proportion of sons than low‐ranking females, and factors other than rank did not have significant effects on birth sex ratios. Interbirth intervals following daughters were longer than those following sons, but they were independent of the mother's rank. The sons of high‐ranking mothers had better survival prospects than sons of low‐ranking mothers in some of the groups; no such difference was found for daughters. Overall, there was no sex difference in survival up to 5 years of age. These results support the Trivers‐Willard hypothesis rather than the local resource competition hypothesis. An analysis of interbirth intervals suggested that the deviation in birth sex ratio is already established at conception.
Mother‐infant interactions in captive slow lorises (Nycticebus coucang)
Authors: Ehrlich Annette , Macbride Lynn
Published: June 2005

Information is presented about mother‐infant interactions and infant development in a rarely studied prosimian primate, the slow loris (Nycticebus coucang). Four dyads were observed, by means of closed circuit TV, in a semi‐natural environment for 1 hour per day three times a week. Infants were inactive for the first 6–8 weeks. Although mothers carried infants, they also left them alone for substantial periods of time after the 1st week. Over the 20‐week study period, there was a significant decline in ventral contact but not in sitting within 12 inches or engaging in active social interactions. By the end of the study, infants were not yet fully independent. Three of the 4 were primarily responsible for maintaining physical closeness to the mother; they made most of the approaches and mothers made most of the departures. However, only 2 of the 4 infants had assumed responsibility for the initiation and maintenance of social interactions with the mother. By comparison with other nocturnal prosimians of similar size, the rate of development is relatively slow. Unlike many anthropoids, mothers were not strongly protective or rejecting. They did not bring infants back to a fixed location or try to prevent infants from leaving them; and the decline in ventral contact was not accompanied by fights between the pair. The 3 group‐living mothers were more protective than the single individually housed mother, and it would seem advisable to isolate mother‐infant pairs in laboratory breeding colonies.
Population structure of Hylobates concolor in Bawanglin Nature Reserve, Hainan, China
Authors: Zhenhe Liu , Yongzu Zhang , Haisheng Jiang , Southwick Charles
Published: June 2005

The Hainan gibbon continues to survive in Bawanglin Nature Reserve in four social groups totalling 21 individuals. Twelve births have occurred since 1982, and 11 of these individuals survive in 1989. Only three of these 12 births have been females, however. The total female population consists of 6 adult females, two of which are at least 19 years old, and three juvenile females born since 1985. Two of the four social groups have only one adult female each and no juvenile females. All four groups are well protected, but their survival is precarious.
Cotton‐top tamarins (Saguinus (o.) oedipus) in a semi‐naturalistic captive colony
Authors: Price Eluned C. , McGrew W. C.
Published: June 2005

To test the prediction that the breeding success of captive cotton‐top tamarins (Saguinus (o.) oedipus) could be improved by maintaining them in groups whose size and age‐sex composition resembled those of wild groups, data were collated from 6.5 years of records from a breeding colony that otherwise had housing and husbandry procedures similar to those of other successful colonies. Group size and composition in the colony closely resembled those of wild groups, and infant survival was the highest yet reported for the species, with 69% of the 124 infants born reared by their parents to adulthood, and a mean surviving litter size of 1.5 infants. Abortion, stillbirth, and parental neglect of infants were rare. Parity had several effects on reproduction: mean litter size decreased, but percentage infant survival increased; interbirth intervals decreased in length; and seasonality in reproduction was more pronounced for the first four litters born to breeding females than for their subsequent litters, with a birth peak in the spring. Although a spacious and complex physical environment, retention of offspring in their natal families until experience of several sets of infant siblings had been obtained, and non‐invasive husbandry and research techniques may all have contributed to the colony's success, it seems possible that the improvement over other colonies is due to the resemblance of group composition to those of wild tamarins.
Incisor microwear and feeding behavior in Alouatta seniculus and Cebus olivaceus
Authors: Ungar Peter S.
Published: June 2005

Dental microwear features on the labial surfaces of maxillary central incisors of wild‐shot museum specimens of Cebus olivaceus (n = 11) and Alouatta seniculus (n = 7) were examined at 200 × by polarized light microscopy. While wear scratch orientation patterns do not differ between the two samples, Cebus has a significantly higher density of wear features, and displays scratches that extend further cervically. Preliminary observations (n = 50 hours) on anterior tooth use in these species at Hato Masaguaral, in the Llanos of Venezuela, provide suggestions regarding how foraging patterns reported in the literature relate to these microwear differences. Cebus uses its front teeth more frequently in the manipulation of a greater variety of objects than does Alouatta.
Social relationships of mountain baboons: Leadership and affiliation in a non‐female‐bonded monkey
Authors: Byrne R. W. , Whiten A. , Henzi S. P.
Published: June 2005

Instead of close and differentiated relationships among adult females, the accepted norm for savanna baboons, groups of Drakensberg mountain baboons (Papio ursinus) showed strong affiliation of females towards a single male. The same male was usually the decision‐making animal in controlling group movements. Lactating or pregnant females focused their grooming on this “leader” male, producing a radially patterned sociogram, as in the desert baboon (P. hamadryas); the leader male supported young animals in the group against aggression and protected them against external threats. Unlike typical savanna baboons, these mountain baboons rarely displayed approach‐retreat or triadic interactions, and entirely lacked coalitions among adult females. Both groups studied were reproductively one‐male; male‐female relationships in one were like those in a unit of a hamadryas male at his peak, while the other group resembled the unit of an old hamadryas male, who still leads the group, with a male follower starting to build up a new unit and already monopolizing mating. In their mountain environment, where the low population density suggests conditions as harsh for baboons as in deserts, adults in these groups kept unusually large distances apart during ranging; kin tended to range apart, and spacing of adults was greatest at the end of the dry, winter season. These facts support the hypothesis that sparse food is responsible for convergence with hamadryas social organization. It is suggested that all baboons, though matrilocal, are better categorized as “cross‐sex‐bonded” than “female bonded”.