bluuebunny/crossref_metadata_2025 huggingface dataset:
Reproductive synchrony in captive macaques
Authors: Silk Joan B.
Published: June 2005

Captive bonnet macaques housed at the California Primate Research Center reproduce seasonally. The chances of producing surviving infants were substantially reduced among females who conceived at the peak of the mating season compared with females whose conceptions were more isolated in time. Primiparous females and low ranking females were most consistently affected by the extent of reproductive synchrony. Behavioral data suggest that harassment of conceiving and pregnant females may have contributed to the correlation between the extent of reproductive synchrony and infant mortality as the levels of aggression toward females were highest during the months in which conceptions were most common.
Observations of parturition among captive patas monkeys (Erythrocebus patas)
Authors: Hemmalin Holly , Loy James
Published: June 2005

Six cases of labor and delivery by laboratory‐housed patas monkeys (Erythrocebus patas) are described. Five of the births occurred during the daytime, and the sixth occurred just after the usual “lights out” time. Although it was impossible to determine the actual onset of labor, the final 1.5–0.5 hr before parturition were observed in all cases. Throughout labor, females tended to begin a contraction every 2–4 min and contractions usually lasted 35–60 sec. Females did not show common patterns of change in contraction frequency or duration as birth neared. It was not possible to describe patas monkey labor and delivery in terms of “stages.” Postpartum, females typically began cleaning their infants within 90 sec and picked them up within 5 min. Placental delivery times varied among females, as did the extent of placental consumption. One “mother‐only” ‐ reared female proved to be an inadequate mother.
Reproduction in wild female olive baboons
Authors: Smuts Barbara , Nicolson Nancy
Published: June 2005

The purpose of this paper is to evaluate several factors that influence female reproduction in a large troop of wild olive baboons (Papio cynocephalus anubis) based on 4 consecutive years of demographic data. Interbirth intervals were significantly shorter for females whose infants died before their next conception than for females whose infants survived. High‐ranking mothers of surviving infants had significantly shorter birth intervals than comparable low‐ranking mothers, independent of maternal age. This occurred mainly because the interval from resumption of cycling to conception was significantly shorter for high‐vs. low‐ranking females. Dominance rank did not influence sex ratio at birth, infant survival in the first 2 years, or adult female mortality. Age was also significantly related to interbirth intervals, with older females having shorter intervals. Primiparous females had consistently longer reproductive intervals than did multiparous females, but this difference reached statistical significance only for females whose infants died before the next conception. Primiparous females also experienced significantly higher infant mortality. Data on body size and estrous cycle length indicated no differences between high‐ and low‐ranking females. Nutritional and stress‐related mechanisms that may underlie the reproductive advantages of high rank are discussed.
Effects of management methods, social organization, and physical space on primate behavior and health
Authors: Erwin Joseph , Sackett Gene P.
Published: June 2005

The incidence of clinical treatment in a large colony of pigtailed macaques (Macaca, nemestrina) was studied retrospectively to assess the effectiveness of three sequential housing and management protocols. In the initial standard protocol, groups were housed in single rooms, with each room occupied by a different group after daily cleaning. In the experimental protocol, animals were housed in two‐room suites dedicated exclusively to the resident group. This protocol was meant to reduce enteritis due to communication of Shigella flexneri across groups. Isolation of groups was coupled with the doubling of available space in an attempt to reduce stress. Under a final compromise protocol, a two‐room suite was dedicated to each group, but the group occupied only one room at a time. The compromise protocol maximized isolation and reduced the available space to the level under the standard protocol. Thus, the study involved two main factors, the degree of group isolation and the amount and configuration of physical space available to each group. Under the experimental conditions enteritis increased, other communicable diseases did not decrease, and trauma from fighting increased by over 45% even though more space was available. Under the compromise conditions, trauma, enteritis, respiratory disorders, and inflammation all decreased markedly. Behavioral studies identified beneficial social behavior patterns associated with spatial reduction as the basis of the decrease in aggression, trauma, and disease under the compromise conditions.
Proboscis monkey (Nasalis larvatus) social organization: Group structure
Authors: Yeager Carey P.
Published: June 2005

Proboscis monkey (Nasalis larvatus) social organization was studied at the Tanjung Puting National Park in Kalimantan Tengah, Indonesia, for 12 months. Data were collected on one‐male groups and all‐male groups by using scan sampling and event sampling while following groups. Evening census surveys were also conducted. Proboscis monkeys were found to follow the typical Asian colobine pattern of one‐male social groups, with extra‐group males forming all‐male groups. These groups appear stable, with few changes in membership. One‐male groups appear to be “female bonded”; adult females direct affiliative behaviors towards their offspring and other adult females, not towards the male. Nearest‐neighbor data indicate some peripheralization of juvenile animals.
Three new blood groups of rhesus monkeys
Authors: Frederick D. L. , Samples N. K. , Stone W. H.
Published: June 2005

Three new blood group systems, called “T,” “U,” and “V,” have been identified in the rhesus monkey (Macaca mulatta). Each system consists of a single antigenic factor (blood group) detected by a monospecific alloimmune reagent that agglutinates erythrocytes. The antisera that detect these blood groups were obtained following a series of alloimmunizations and absorption fractionizations of the resulting antisera to produce operationally monospecific typing reagents. Analyses of family data indicated that each blood group was controlled by an autosomal dominant gene and that each system was independent of previously defined systems. With the addition of these new blood groups, we can identify 16 different blood group systems and well over one hundred million possible phenotypes in this species.
Choice of food patches by Japanese monkeys (Macaca fuscata)
Authors: Nakagawa Naofumi
Published: June 2005

Food patch choice was investigated in the A‐troop of wild Japanese monkeys (macaca fuscata) of Kinkazan Island, Japan. The monkeys visited a Zelkova serrata tree 16 times and fed on its seeds for 43.5 min on average during the 36 day study period. The proportion of fallen seeds to total fallen seeds, the feeding speed, and the number of monkeys feeding on seeds in the crown and on the ground were recorded to clarify the decision factors involved in food‐patch choice: when the monkeys visit the tree, do they feed on seeds in the crown or on the ground? The monkeys appeared to the patch quality by feeding speed; they chose a high‐quality patch and fed there. As a result, they seemed to maximize seed intake. However, some troop members (in many cases, low‐ranking ones) avoided feeding in a high‐quality but crowded patch. When the quality of the two patches was equal, the monkeys separated into two groups (in the crown and on the ground) in a ratio of 1:1 to feed. As the difference in patch quality became larger, more monkeys fed in the high‐quality patch. The frequency of agonistic interactions per individual increased on the ground as the number of monkeys feeding there increased. When the cost of agonistic interactions is considered, the net benefit (energy intake minus energy consumption from agonistic interactions) per individual in a higher‐quality but crowded patch may be equal to that in a lower‐quality but uncrowded patch.
Reactivity patterns of class I HLA monoclonal antibodies that distinguish three species of macaques
Authors: Gaur Lakshmi K. , Heise Eugene R. , Clark Edward A.
Published: June 2005

The reactivity of a panel of 40 monoclonal antibodies (mAb) specific for HLA class I antigens was assessed in 117 unrelated Macaca mulatta (Mm), with a standard microcytotoxicity assay, in order to compare phenotypic frequencies with those previously reported for M. fascicularis (Mfl) and M. nemestrina (Mn). Based on the reactivity with HLA typed human cell panels, the epitopes recognized by these mAb in macaques were classified as nonpolymorphic, polymorphic “public,” and polymorphic “private.” Nei's genetic identity (I) and distance (D) formulae were applied to estimate I and D between each of the macaque species and between each macaque species and humans. The HLA nonpolymorphic epitopes emerged as spcies‐specific determinants, as all three macaque species showed clear differences from each other and from humans in the frequency of occurrence in population samples. From our previous serologic study and from published sequence data, it is evident that the major histocompatibility complex (MHC) is highly conserved in primate evolution. Ninety percent of the mAb reacted at a similar frequency in either two or three macaque species. With few exceptions, the mAb reacted at a greater frequency in humans than in macaques. Concerning private HLA class I epitopes, we have previously speculated that the human MHC class I polymorphisms probably predate the diversification of macaque–human lineages, and hence would be highly conserved. However, the inconsistent pattern of occurrence of human monomorphic epitopes among the macaque species suggests that a complex explanation is required. One possibility is that HLA monomorphic epitopes are invariant in humans because of their yet unknown functional role; however, this explanation loses some force because of the inconsistent pattern of occurrence among three closely related species of Macaca. However, we favor a second possibility, i.e., that the monomorphic epitopes in humans might be the result of the accumulated neutral mutations and are not subjected to functional constraints. This explanation seems to fit the inconsistent pattern of occurrence of these epitopes among macaques.
Discrimination of chirp vocalizations in the cotton‐top tamarin
Authors: Bauers Kim , Snowdon Charles T.
Published: June 2005

Natural exemplars of two types of chirp vocalizations were presented to eight groups of cotton‐top tamarins (Saguinus o. oedipus) in a playback paradigm. The two chirps share many acoustic features in common but are used in entirely different circumstances. The tamarins gave different vocal and behavioral responses to the playbacks of each chirp type, indicating that a discrimination was made. The results suggest that tamarins can discriminate subtle acoustic cues which have communicative significance. In the absence of the nonvocal cues and social contexts that normally co‐occur with these vocalizations the tamarins responded with the same vocal responses they would have given in normal social contexts. Significant differences in post‐stimulus behavior to the two types of stimuli appeared in the first two blocks of trials, indicating that the playback paradigm can be an efficient means of testing discrimination between different call types.
Reproduction of the owl monkey (Aotus nancymai) (primates:Cebidae) in captivity
Authors: Gozalo Alfonso , Montoya Enrique
Published: June 2005

There are few reports and poorly documented field studies about the reproductive biology of the owl monkey (Aotus spp.). Reproductive data were collected from a breeding colony of owl monkeys (Aotus nancymai) held at the Center for Reproduction and Conservation of Non‐Human Primates in Iquitos, Peru, for the past 10 years. Seventy nine breeding pairs have produced 180 offspring in a period of 3,619 months, representing an average of about one offspring for every 20 months that a pair was housed together. Neonatal mortality in the first week was 7.1%. Litter size was almost one (99.4%). The mean age at first birth in a group of nine females born in captivity was 40.56 ± 7.82 (S.D.) months. The mean age of a group of 12 males born in the colony when their female mates produced offspring was 42.17 ± 10.73 (S.D.) months. Gestation length did not exceed 141 days. Interbirth interval averaged 12.72 months. A birth peak was observed from October to January. Breeding Aotus nancymai on a large scale in captivity is feasible.
Mixed‐species association of East African guenons: General patterns or specific examples?
Authors: Cords Marina
Published: June 2005

Sympatric guenons in East Africa associate with one another in mixed‐species groups to an intermediate degree. This makes it possible to compare a given group's ecology and behavior when it is part of an association to when it is unaccompanied, and to correlate association tendency with various ecological parameters. Two studies incorporating these approaches have been made of sympatric Cercopithecus ascanius and C. mitis monkeys in the Kakamega Forest, Kenya, and the Kibale Forest, Uganda. The pattern of and reasons for association in each site are reviewed. Compared to Kakamega, association between C. ascanius and C. mitis in Kibale occurs less often, and the species appear to benefit relative to one another in different ways. These results suggest that the particular ecological setting greatly influences the nature of the interaction between species, through its effect on population structure, dietary overlap, food distribution, and community composition. The major ecological differences between the two study areas probably reflect post‐Pleistocene history and possibly climate, but they have important consequences for the present‐day population structure and feeding ecology of each species, and hence affect relations between them as well.
Interspecific relations in a mixed‐species troop of moustached tamarins, Saguinus mystax, and saddle‐back tamarins, Saguinus fuscicollis (Platyrrhini:Callitrichidae), at the Río Blanco, Peruvian Amazonia
Authors: Heymann Eckhard W.
Published: June 2005

This study examined the social interactions between moustached tamarins, Saguinus mystax, and saddle‐back tamarins, Saguinus fuscicollis, living in a mixed‐species troop at the Río Blanco, Peruvian Amazonia, between July 1985 and July 1986. Mixed‐species troops were common among the S. mystax and S. fuscicollis populations in the Río Blanco study area; 72% of all sightings of S. mystax and 82% of all sightings of S. fuscicollis were in mixed‐speices troops (study group excluded from analysis). In the study group, the two species spent on average 82% of time in association. Interactions were observed at a rate of one per 5 h of observation. Most interactions (96%) were agonistic. About 70% of agonistic interactions occurred at small food resources (crown diameter < 5 m and/or limited number of ripe fruits). Moustached tamarins were always dominant over saddle‐back tamarins. Friendly interactions were extremely rare and were restricted to play invitations. Mutual calling was observed in the morning before the two species joined each other and during the day when they became separated. It is concluded that interspecific interactions and mutual calling incur some costs to the associated species but that these costs may be low.
A study of locomotor behavior in a captive colony of red‐bellied lemurs (Eulemur rubriventer)
Authors: Tilden Christopher D.
Published: June 2005

The considerable diversity of locomotor behavior within the suborder Prosimii largely is due to differences in locomotion between families. Within families, locomotion is relatively homogeneous, although some species, such asOtolemur crassicaudatusamong the galagids andHapalemur simusandLepilemurspp. among the lemurids, differ from other species in their family. This paper describes the locomotion of a captive colony of red‐bellied lemurs,Eulemur rubriventer(following the classification of Simons and Rumpler [1988] who place all species ofLemurother thanLemur cattain the genusEulemur), another species whose movements differ markedly from other members of its family, the Lemuridae. Features that distinguish the locomotion ofE. rubriventerfrom other lemurids are the high frequency of leaping, low frequency of climbing and suspension, and the use of head‐downward vertical climbing in this species. Leaping is the most common form of locomotion inE. rubriventer. Horizontal, rather than vertical supports, are preferred during leaping. Although the frequency of climbing in this study is relatively low, the large brachioradialis flange, robust hallux, and claw‐like nails ofE. rubriventersuggest that clinging and climbing on large diameter vertical supports (lacking in the enclosures used in this study) may be an important component of locomotion in wildE. rubriventerand may reflect a gummivorous or insectivorous dietary adaptation. While the locomotion ofE. rubriventerdiffers from all prosimians yet studied, the general pattern of locomotor behavior seen in this species is most similar to other species of the family Lemuridae.
The reduction of abnormal behaviors in individually housed rhesus monkeys (Macaca mulatta) with a foraging/grooming board
Authors: Bayne K. , Mainzer H. , Dexter S. , Campbell G. , Yamada F. , Suomi S.
Published: June 2005

A new environmental enrichment device, termed a “foraging/grooming board,” was presented to 8 individually housed rhesus monkeys for the explicit purpose of reducing the level of aberrant behaviors manifested by these animals. The device, consisting of a piece of plexiglass covered with artificial fleece, had particles of food treats rubbed into it and was attached to the outside of each animal's home cage. All animals foraged from the board to the point that a significant reduction in the level of abnormal behavior was noted. Most animals also groomed the fleece covering the board, utilizing the same motor patterns that would be directed toward grooming another monkey. These boards are inexpensive to construct and easy to sanitize, and do not require placing animal facility personnel at risk to maintain them.
Distribution of terrestrial herbaceous vegetation and its consumption by Pan paniscus in the Lomako Forest, Zaire
Authors: Malenky Richard K. , Stiles Edmund W.
Published: June 2005

Data available on behavior and morphology of Pan paniscus (bonobos) suggest that terrestrial herbaceous vegetation (THV) is an important component of their diet and that it may be preferred by bonobos to a greater extent than by chimpanzees (Pan troglodytes). It has also been reported that THV is ubiquitously distributed in the lowland rain forests inhabited by bonobos. These data suggest that THV exploitation may be causally related to the evolution of the more cohesive social system found in bonobos compared to that of chimpanzees. Here, we present data that quantify the spatial distribution of THV in the Lomako Forest, an analysis of the nutrient content of the plant parts commonly consumed, and patterns of THV consumption in relation to its distribution. The data clearly demonstrate that THV, and particularly Haumania liebrechtsiana (Marantaceae), is ubiquitously distributed as previously suggested. However, THV feeding patches are rare because of distinct feeding preferences. Bonobos preferentially choose H. liebrechtsiana over other species of THV, choose patches with larger stems, and, within patches, choose larger stems over smaller stems. The plant parts chosen are high in proteins and relatively low in carbohydrates. Given the selectivity of the study population and the patchy distribution of THV, it is unlikely that THV has been responsible for the evolution of the unique social system reported for bonobos. Data presented on party size are consistent with this conclusion.
Spectral sensitivity of vervet monkeys (Cercopithecus aethiops sabaeus) and the issue of catarrhine trichromacy
Authors: Jacobs Gerald H. , Neitz Jay , Crognale Michael A. , Brammer Gary L.
Published: June 2005

Several genera of platyrrhine monkeys show significant polymorphism of color vision. By contrast, catarrhine monkeys have usually been assumed to have uniform trichromatic color vision. However, the evidential basis for this assumption is quite limited. To study this issue further, spectral sensitivity functions were obtained from vervet monkeys (Cercopithecus aethiops sabaeus) using the technique of electroretinographic flicker photometry. Results from a chromatic adaptation experiment indicated that each of the twelve subjects had two classes of cone pigment in the 540/640 nm portion of the spectrum. That result strongly suggests that this species has routine trichromatic color vision. Comparison of the spectral sensitivity functions obtained from vervets and from similarly‐tested humans further indicates that the cone complements of the two species are very similar. Results from this investigation add further support to the idea that there are fundamental differences in the genetic mechanisms underlying color vision in platyrrhine and catarrhine monkeys.
Urinary cyclic AMP excretion is increased in Macaca fascicularis and Macaca mulatta compared to humans
Authors: Stock John L. , Coderre James A. , Simon James A.
Published: June 2005

Changes in parathyroid hormone and its second messenger cyclic AMP have been implicated in the pathogenesis of osteoporosis. Nonhuman primate models have been useful in the study of osteoporosis, but the physiology of mineral metabolism in certain species is different than in humans. We investigated parameters of mineral metabolism in 15 normal adult female cynomolgus and 14 normal adult female rhesus monkeys. In both species, urinary cyclic AMP was increased compared with humans, and the nephrogenous cyclic AMP in the cynomolgus monkeys was also elevated. Despite this, there was no evidence for hyperparathyroidism in either species as evaluated by serum or plasma phosphorus and midregion‐specific and/or aminoterminal‐specific immunoreactive parathyroid hormone. Given the increasing use of nonhuman primates in the study of osteoporosis, understanding basic changes in mineral metabolism is important before pathologic effects of bone loss can be understood.
Stability of social status rankings of female cynomolgus monkeys, of varying reproductive condition, in different social groups
Authors: Shively Carol A. , Kaplan Jay R.
Published: June 2005

In order test the hypothesis that adult female macaques display a tendency to attain a certain level of social status independent of the social situation, the social status rankings of 41 wild‐caught adult female Macaca fascicularis were determined in different social groups. About one‐third of the females were intact and housed with vasectomized males. About one‐third of the females were ovariectomized and housed with intact males, and the remaining females were intact and housed with intact males in order to allow pregnancy to occur. Within each of these experimental groups, females were housed in social groups of 4–6 females and 1 male, and the constituency of these groups was changed every 3 months for 22 months. Thus, females lived in eight different social groups. The correlations between the social status rankings of individual females while living in different social groups were positive and significant. The majority of the females were either stable dominants or stable subordinates in 75% of the groups in which they lived, which was a significant proportion of the study population. The stability of social status rankings was higher in the ovariectomized than in the pregnant and intact groups; however, this was not a significant difference. In the context of the results of previous studies, these findings suggest that the social status of an individual is the result of both the immediate social environment and some inherent characteristic(s) of the individual that promotes the likelihood that under most social circumstances an individual will display a predictable level of social status.
Urine washing in brown capuchin monkeys (Cebus apella): Testing social and nonsocial hypotheses
Authors: Roeder Jean‐Jacques , Anderson James R.
Published: June 2005

This study tested several hypotheses regarding the functions of urine washing (UW) in a captive group of brown capuchin monkeys (Cebus apella), using observational and experimental methods. Observational data obtained over a 16 month period revealed no correlation between rates of UW and age or aggression. Rates of UW did not vary when the subjects were exposed to their mirror images or when their hands were soiled. Transferring the group to an unfamiliar environment had no effect on UW frequencies. Climatological factors most clearly influenced rate of UW: The behavior occurred more frequently in high temperatures and during sunny periods, indicating a possible role of UW in thermoregulation.
Advances in reproduction in captive, female great apes: Value of biotechniques
Authors: Loskutoff N. M. , Kraemer D. C. , Raphael B. L. , Huntress S. L. , Wildt D. E.
Published: June 2005

Most of the progress in female great ape reproduction has focused on monitoring ovarian and endocrine activity. Perhaps of more importance has been the gradually evolving interest and willingness to consider biotechnology as a potential, viable approach for enhancing reproductive performance. Artificial insemination (AI), in vitro fertilization (IVF), and embryo transfer offer an array of possibilities for combating infertility and understanding the fundamental differences and similarities among great ape species. Multidisciplinary efforts have assessed reproductive competence, from the simple (i.e., perineal tumescence and urinary occult blood in chimpanzees) to the complex (i.e., ovum recovery and IVF following exogenous hormone treatment in chimpanzees and gorillas). Hysterosalpingography and laparoscopy have been used to determine uterotubal patency and to identify pathological conditions in gorillas. Assays for steroid metabolites in serial urine samples, to permit accurate assessments of ovarian cyclicity, have been developed and validated for all great apes species. Stimulation of follicular recruitment and maturation has been achieved following administration of clomiphene citrate (chimpanzees and gorillas) and human menopausal gonadotropin (gorillas). Clomiphene citrate and human chorionic gonadotropin have been used to regulate ovulation for the AI of chimpanzees. Pregnancies have resulted in chimpanzees and gorillas following AI using fresh and cryopreserved/thawed semen; however, conception rates vary. Embryos have been nonsurgically recovered from chimpanzees after timed matings and follicular oocytes have been recovered from chimpanzees and gorillas by transabdominal laparoscopy after exogenous hormone treatment. To date, although in vivo matured ova have been fertilized in vitro using homologous sperm in chimpanzees and gorillas, no great ape offspring have been born from transferred embryos produced by in vitro or in vivo fertilization. A review of the many remaining problems suggests the need for more basic studies of ovulation induction, ovum and sperm requirements in vivo and in vitro, and the effects of animal manipulation (anesthesia, surgery, and other stressors) on the ability of the female to ovulate and sustain pregnancy. Especially important are more assessments to identify reproductively competent individuals so that these females can be placed with breeding males while subfertile or infertile animals are designated for intensive artificial breeding research.
Cyclic changes in hormonal, physical, behavioral, and linguistic measures in a female lowland gorilla
Authors: Patterson Francine G. P. , Holts Candace L. , Saphire Lisa
Published: June 2005

Since 1972, Koko, a captive‐born female lowland gorilla, has been the subject of longitudinal linguistic and behavioral research. Data on behavioral and physical concomitants of Koko's estrous cycle have been gathered since her cycles began at the age of 5 years, 9 months. This study presents evidence of endocrinological influence on cognitive functioning: It demonstrates that frequency of sign‐language use by Koko is greater in the follicular phase of her reproductive cycle. This finding supports an earlier report on Koko and is in agreement with recent studies correlating human menstrual‐cycle phases with patterns of manual sequencing and verbal fluency. This study also confirms that nonlaboratory hormone tests designed for human female urine samples appear to be useful for detecting luteinizing hormone (LH) in gorilla urine and establishes the applicability of such tests for determining pregnanediol‐3‐glucuronide (PdG) levels in gorilla urine. Analyses of preliminary test results indicate that these enzyme immunoassay (EIA) tests match earlier radioimmunoassay (RIA) findings on the relationship between reproductive hormones and variables such as genital swelling and proceptivity in female gorillas.
Mountain gorilla reproduction and sexual behavior
Authors: Watts David P.
Published: June 2005

Data on mountain gorilla reproductive behavior, demography, and sexual behavior are reviewed and compared with earlier reviews of reproduction by wild gorillas and with data on captive gorillas. Topics covered include maturation, female transfer patterns and reproductive histories, reproductive intervals, influences on fertility, infant mortality, sex ratios at birth, birth seasonality, copulatory behavior, and estrus cyclicity. Most of the results of the updated analyses presented here corroborate those from previous studies of the same population. Newer information shows that responsibility for the initiation of copulations varies in association with female fertility and sexual state; that infant mortality in the first year is higher than reported earlier; that the sex ratio at birth is 1:1; and that, on a population level, interbirth intervals following the birth of males are the same length as those after female births. Data on reproductive intervals, sexual cyclicity, and copulatory behavior are generally similar to data from many captive situations. Two findings are particularly relevant to the problem of cessation of reproduction by captive females. First, fertility does not obviously decline with age in the wild. Second, a high proportion of females have reproduced in their natal groups and some have had multiple births there.
Reproductive intervals in captive female western lowland gorillas with a comparison to wild mountain gorillas
Authors: Sievert Judy , Karesh William B. , Sunde Violet
Published: June 2005

A wide disparity between parturition and the resumption of sexual behavior in two captive female western lowland gorillas prompted an investigation of interbirth intervals (IBIs) in captive western lowland gorillas that had reared their infants. To determine reproductive intervals, a questionnaire was sent to 30 institutions (19 in North America and 11 in Europe) that maintained captive females who had previously reared or were currently rearing their offspring. Information compiled relates to the length of reproductive intervals, including lactational anestrus, estrous behavior to conception and from parturition to conception, and IBIs. These data are compared with studies published on wild mountain gorillas. The median IBI for 16 mothers still rearing infants when their next conception occurred was 4 years (range 2.33–6.42 years, N = 16). Twenty‐one percent of the 52 mothers in this study are no longer reproducing. The mean time without reproduction since separation from their last offspring was 5.43 years. This study indicates that the length of IBIs, lactational anestrus, and intervals from parturition, separation, and estrous behavior to conception compare closely with findings for wild populations. Incompatibility between partners may be a factor limiting further reproduction in some captive mothers in this study.
Morphometric analyses of Ateles: systematic and biogeographic implications
Authors: Froehlich J. W. , Supriatna J. , Froehlich P. H.
Published: June 2005

This study examined the cranial and dental morphometric patterns among South American spider monkey taxa (Ateles), using various multivariate data reduction techniques to corroborate or falsify the predictions of alternative vicariance or parapatric models for explaining neotropical biodiversity. Data from 284 specimens were standardized to eliminate sex differences and then transformed by factor analysis to obviate the effects of body size on shape relationships. We found the independent discriminant analyses of dental and cranial data to be not at all dissimilar, nor did body size appear to distort geographical relationships. Thus a pooled data set of 50 measurements was further reduced by cluster analysis to produce a dendrogram of taxonomic relationships that is discordant with current classification. Three independent taxa are indicated, with the Guianan samples being most distinct, followed by the animals of northwest Venezuela and adjacent Colombia. Elsewhere, the samples describe a cline of relationships around Amazonia that resembles a ring species. Of particular interest is the apparent clinal intergradation across major tributaries of the Amazon, which is inconsistent with the concept of these rivers as barriers in their present form. Instead these observations, and the congruence between the multivariate clusters and previously identified centers of endemism, support both tierra firme and forest refugia models of historical biogeography. However, the latter model is somewhat falsified within Amazonia by character stability for alternative pelage patterns on opposite sides of the same major rivers that showed morphometric intergradation, but not as predicted within the refugia. This parapatric enhancement of pelage differences, which originated presumably in allopatry, suggests a mechanism of incipient speciation by frequency‐dependent assortative mating with no apparent hybrid disadvantage or disruption of widespread gene flow.
Suppression of luteinizing hormone release by the α1‐adrenergic receptor antagonist prazosin in the ovariectomized female rhesus monkey
Authors: Gearing Marla , Terasawa Ei
Published: June 2005

The effects of adrenergic antagonists on LH release were examined in ovariectomized female rhesus monkeys implanted with indwelling jugular catheters. While the α2‐adrenergic antagonist rauwolscine and the vehicle were without effect, the α1‐antagonist prazosin suppressed LH release. In 5 of the 8 monkeys tested, LH pulses were completely arrested; in the remaining 3 monkeys, small LH pulses were detectable after the administration of 0.2 mg/kg prazosin. In a second series of experiments, the effects of three different doses of prazosin were examined. Doses of 0.1 mg/kg and 0.4 mg/kg suppressed LH release in a manner indistinguishable from that of the 0.2 mg/kg dose. Finally, the ability of the pituitary to respond to a bolus of LHRH during the prazosin‐induced suppression was tested. In all 6 animals, the injection of LHRH during the time when LH was suppressed by prazosin resulted in a marked increase in LH release. These results indicate 1) that α1‐adrenergic receptors but not α2 receptors are important for pulsatile LH secretion, 2) that varying the dose of prazosin administered does not alter the effect of the drug or LH release within the range of doses tested, and 3) the pituitary is able to respond to LHRH with an increase in LH release during the prazosin‐induced suppression period.
Axial skeleton of Cebupithecia sarmientoi (Pitheciinae, Platyrrhini) from the middle miocene of La Venta, Colombia
Authors: Meldrum D. Jeffrey , Lemelin Pierre
Published: June 2005

The axial skeleton of Cebupithecia sarmientoi is described and analyzed for its functional and phylogenetic implications. The vertebrae of the holotype of C. sarmientoi (UCMP 38762) most closely resemble those of the extant pitheciine genus Pithecia and display features associated with adaptations for clinging and leaping as in that genus. Cebupithecia has a relatively long non‐prehensile tail, which is most similar in absolute dimensions and proportions to Pithecia monachus. It also shares with P. monachus a distinctive morphology of the thoracic vertebrae, specifically the presence of a bony pillar spanning the vertebral lamina and body, caudal to the pedicle, herein designated the vinculum laminum. It is proposed that many of these features are shared primitive retentions from the last common ancestor of the Cebupithecia‐pitheciine clade.
Factors in the rejection and survival of captive cotton top tamarins (Saguinus oedipus)
Authors: Johnson Lorna D. , Petto Andrew J. , Sehgal Prabhat K.
Published: June 2005

Captive colonies of cotton top tamarins experience a high rate of rejection of infants within the 1st week of life. The rates of rejection and survival to maturity (2 or more years) among 659 live colony‐born infants were correlated with rearing, birth group, litter size, season of birth, gender, origin of parents, experience of parents raising siblings, parity and age of parents, and experience of parent pairs. The most important factors associated with low rejection rates were family life and parental experience raising infants. Infants born into family groups or reared in families were rejected at a significantly lower rate. Rejection of infants whose sires were raised with siblings was significantly lower. Paternal experience was more important than maternal experience. Litter size had no effect on rejection of infants born to family groups, whereas, rejection of triplets was significantly higher than twins or singles among those born to parents alone. Rejection was significantly higher among primiparous births than multiparous birth. The combined experience of colony‐born parents was not related to rejection if there were no sibling helpers in the cage at the time of birth. Rejection was significantly lower if sibling helpers were present. High survival of infants who were not rejected was correlated with rearing by or being born into family groups and higher parity and older age of the sires.
ACTH and glucocorticoid responses under two conditions of stress in macaques
Authors: Clarke A. Susan
Published: June 2005

Female macaques were tested under two different psychologically stressful situations in which plasma ACTH and glucocorticoid concentrations were measured. In the first, animals were operantly trained to enter a small transport cage over a four‐week period, and plasma ACTH and glucocorticoids were measured in response to brief confinement in the cage before and after training. ACTH values were significantly lower in the pre‐test (stress) condition when compared to those for the post‐test, whereas the opposite result was found for glucocorticoid values. In the second experiment, blood samples were collected before and one hour after exposure to more acute and severe stress (restraint, venipuncture, handcapture, transport). Both ACTH and glucocorticoid values were significantly elevated from baseline at the post‐test sample. The differential relationship between the two hormones among the two experiments was likely the result of the specific timing and magnitude of the stress imposed by each test situation.
The relationship of agonistic and affiliative behavior patterns to cellular immune function among cynomolgus monkeys (Macaca fascicularis) living in unstable social groups
Authors: Kaplan Jay R. , Heise Eugene R. , Manuck Stephen B. , Shively Carol A. , Cohen Sheldon , Rabin Bruce S. , Kasprowicz Alfred L.
Published: June 2005

Considerable recent interest has focused on the possibility that behavioral factors may influence immune competence, and hence, potentially, patterns of disease. We report here the relationship between the aggressive and affiliative behavior and the cellular immune responses of 30 adult male cynomolgus monkeys (Macaca fascicularis) living in small (n = 5) social groups whose members were periodically redistributed over 26 months. Animals also were subjected to behavioral observation, allowing them to be categorized as either high or low in aggressiveness and affiliation. At the end of the 26 months, lymphocyte proliferation tests were performed on blood samples from all monkeys, using both concanavalin A (ConA) and phytohemagglutinin (PHA) in concentrations of 1, 5, and 10 ug/ml. Two‐by‐two (Aggressiveness [high, low] X Affiliation [high, low]) analyses of variance performed on these data showed lymphocyte proliferation in response to both ConA and PHA to be greatest (at 1 ug/ml) among highly affiliative animals, albeit only if they were also low in aggressiveness (ConA: Affiliation x Aggression, P < 0.02; PHA: Affiliation x Aggression, P < 0.03). An additional finding was that natural killer cell activity (at an effector to target ratio of 100:1) was highest among highly affiliative animals, regardless of their aggressiveness (P < 0.05). These results indicate that immune competence may be enhanced among monkeys which, in response to a disrupted social environment, spend large amounts of time in affiliation with other animals. Social status, a phenomenon known to influence many aspects of nonhuman primate physiology, was unassociated with nonspecific lymphocyte blastogenesis or natural killer cell activity in this experiment.
Population ecology of rhesus monkeys (Macaca mulatta) at Nanwan Nature Reserve, Hainan, China
Authors: Jiang Haisheng , Liu Zhenhe , Zhang Yongzu , Southwick Charles
Published: June 2005

Rhesus monkeys (Macaca mulatta) at the Nanwan peninsula of Hainan Island, China, have been observed in the field for 25 years, and have been studied intensively for eight years, beginning in 1981. There were about 115 monkeys in 5 natural groups when the Nanwan Reserve was founded in 1965. From 1965 to 1984, the number of groups increased from 5 to 19, and the total population increased from 115 to 930 individuals, an annual population increase of 12.7%. From 1984 to 1987, the population continued a slower rate of increase (8.9%) to approximately 1200 monkeys in 20 groups. The home ranges of each monkey group at Nanwan varied from 0.16 to 0.72 km2, with a mean and standard deviation of 0.37 ± 0.18. The size of the home range of the rhesus was affected by the quality of vegetation and rhesus population density. The average birth rate per year was 77.8 ± 13.9%, varying from 53.8% to 100% since 1978. From 1978, the birth rates of two food provisioned groups were higher in alternate years (x̄ = 91.7%) and lower in intervening years (x̄ = 68.8%; P = <0.01). A minority (26.5%) of females have given birth at 4 years of age, most at 5 years. The sex ratio of newborns in any one year varied from 0.3 to 3.5 males to females, with a mean and standard error of 1.09 ± 0.37 males to females.
Some contrasting effects of surgical and “chemical” castration on the behavior of male cynomolgus monkeys (Macaca fascicularis)
Authors: Zumpe Doris , Bonsall Robert W. , Michael Richard P.
Published: June 2005

In nonhuman primates, surgical castration reduces plasma testosterone levels and male sexual behavior, and testosterone replacement restores them. Chemical castration with compounds that lower plasma testosterone levels is used clinically in the treatment of certain forms of cancer and to reduce aberrant sexual behavior in male sex offenders. In the United States, medroxyprogesterone acetate (MPA) is the drug most used to help reduce serious sexual behavioral problems in men. We were therefore interested in comparing the behavioral effects of MPA treatment (40 mg once a week) in 4 intact male cynomolgus monkeys (4 pairs, 120 tests) with data from an earlier study in our laboratory on 4 males observed before and after surgical castration (16 pairs, 192 tests). Both MPA treatment and surgical castration reduced plasma testosterone to very low levels and decreased ejaculatory activity, but MPA treatment additionally affected measures of male sexual motivation (decreased numbers of male mounting attempts and increased mounting attempt latencies) which were not primarily affected by surgical astration. However, surgical castration decreased intromission ability (percentage of intromitted thrusts per test) and male yawning behavior more rapidly than did MPA treatment. This suggested a hypothesis that different mechanisms could be involved in the behavioral effects—namely, that surgical castration may act primarily via testosterone‐dependent peripheral mechanisms, while chemical castration with MPA does so primarily via central mechanisms regulating sexual motivation.
The stimulatory effect of males on the initiation but not the maintenance of ovarian cycling in cotton‐top tamarins (Saguinus oedipus)
Authors: Widowski Tina M. , Porter Teresa A. , Ziegler Toni E. , Snowdon Charles T.
Published: June 2005

Prior studies have shown that female cotton‐top tamarins usually do not ovulate while living with natal groups, and most females do not ovulate until they are paired with an unfamiliar adult male. To examine the role of unfamiliar adult males on stimulating ovarian function, four cotton‐top females were studied during three conditions: females living with their natal group for six weeks, living alone but exposed to a single unfamiliar adult male located 15 cm away from the female's cage for four weeks, and living with an unfamiliar adult male for six weeks. Behavior and urinary hormonal concentrations were measured during the three conditions. Exposure to the male consisted of visual, auditory, and airborne olfactory contact. First ovulation occurred during exposure to the unfamiliar male in three of the four females indicating that direct physical or sexual contact with the male is not required for onset of ovarian cycling. The fourth female did not ovulate even during six weeks of direct contact with the unfamiliar adult male. In addition, four parous females in either family groups (3) or singly caged (1) were examined for ovarian function 4–6 months after the death or removal of their mates. All femals continued to cycle in the absence of the male indicating that the male was not needed to continue ovarian cycling. In fact, two of the females were pregnant at the time their males died and both delivered normal infants and resumed cycling. The results of this study indicate that an unfamiliar adult male may facilitate the onset of ovarian cycling without being in direct contact with the female and visual, auditory, or airborne olfactory cues may be involved. Once repeated ovarian cycling occurs the male is not required to maintain ovarian function.
Proboscis monkey (Nasalis larvatus) social organization: Nature and possible functions of intergroup patterns of association
Authors: Yeager Carey P.
Published: June 2005

Proboscis monkey (Nasalis larvatus) socioecology was studied at the Natai Lengkuas Station, Tanjung Puting National Park, in Kalimantan Tengah, Indonesia. Data on the nature of intergroup interactions were collected on ten one‐male groups and two all‐male groups using event sampling during follows and also through evening census surveys. Proboscis monkeys form stable one‐male groups, with specific groups regularly associating at their sleeping sites (band members). Both intraband and interband high‐intensity agonistic displays (slapping, chasing, biting) were rare. Lower intensity agonistic displays (vocalizations, leaping‐branch shaking, and erect penis and open‐mouth displays) occurred frequently. Temporal avoidance between bands may have been mediated by early morning vocalizations and branch shaking displays by the adult males. Associations between groups may play a role in displacement avoidance and/or predation avoidance.