bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ramapithecus and Sivapithecus from China: Some implications for higher primate evolution
Authors: Rukang Wu , Oxnard Charles E. 
Published: June 2005

AbstractThe pattern of overall dental dimensions in over 900 teeth of ramapithecines from Lufeng in China is examined using frequency distribution histograms and fitted normal curves, and compared with data for extant hominoids. A prior study has demonstrated unequivocally that at least two groups of animals must have existed at Lufeng [Wu and Oxnard, 1983; Oxnard, 1983a]. The present investigation confirms this finding in more detail. In addition it shows that one fossil group possesses smaller teeth with a lesser degree of sexual dimorphism and approximately equal numbers of adult males and females, and the other possesses larger teeth with a rather larger degree of sexual dimorphism and a female‐male ratio that may have approximated from as low as 2:1 to as high as 4:1. Comparisons of patterns of difference along the tooth row demonstrate that both these forms differ from modern apes in their sexual dimorphism, the smaller form being more like humans than the larger, which is more like apes, especially orangutans. Comparisons of the areas of the canine teeth with each of the other functional segments of the tooth row again show that the smaller form is basically similar to modern humans and that the larger resembles extant great apes. Comparisons of other functional dental areas seem to relate to dietary and masticatory functions. Thus the cutting areas are large relative to the chewing areas in omnivorous humans, whereas in the essentially vegetarian great apes this ratio is smaller. The smaller fossil resembles the human condition and may have been somewhat omnivorous; the larger one more resembles the apes and may have been somewhat more vegetarian. However, these comparisons also show that the way in which the larger form resembles the apes is associated with special development of the canines, which is different from that in any modern ape. Comparisons show that the canines in the larger form project far beyond the normal line of tooth crowns. Finally, comparisons show that canine sexual dimorphism in height is marked in the larger form. Neither of these last two features is true of the smaller fossil. These findings have implications for our understanding of the evolution of early pongids and hominids, and for the evolution of primate sexual dimorphisms and dental mechanisms.
Brief report: Crocodile predation on a crab‐eating macaque in Borneo
Authors: Galdikas Biruté M. F. , Yeager Carey P. 
Published: June 2005

AbstractAn immature crab‐eating macaque (Macaca fascicularis), which was sitting on the river bank near the Orangutan Research and Conservation Project base camp in the Tanjung Puting Reserve, Kalimantan Tengah, Indonesia, was seized by a crocodile which rapidly emerged from the water and then resubmerged with the monkey in its jaws. As crocodile populations are in a decline throughout Borneo, crocodile predation on crab‐eating macaques was probably more frequent in the past. This predation may have influenced development of some behaviors with an antipredator function in M. fascicularis.
Fruit eating and seed dispersal by howling monkeys (Alouatta palliata) in the tropical rain forest of Los Tuxtlas, Mexico
Authors: Estrada Alejandro , Coates‐Estrada Rosamond 
Published: June 2005

AbstractThe frugivory and ranging habits of howling monkeys living in the rain forest of Los Tuxtlas, Veracruz, Mexico, were studied for 5 consecutive years with the aim of investigating the role of seed dispersal agents played by the howling monkeys. The howling monkeys' consumption of fruit occupied half of their feeding time, and 80% of this time was spent feeding on mature fruit. Observations confirmed use of 19 tree species and a preference for a few species of Moraceae and Lauraceae. Fruit exploitation was very seasonal; only two species provided fruit year‐round. Home range size was about 60 ha, and animals in the troop (N = 16) showed a day range of 10–893 m. Monthly collection of fecal samples during 2 years indicated that 90% of the seeds (N = 7,928) in the samples belonged to eight tree species and to one liana; the rest belonged to 15 unidentified species of vines. Germination success for the seeds in the feces was about 60% and for control seeds was 35%. Howling monkeys created diverse seed shadows in the vicinity of their leaf and fruit sources, and while they dispersed the seeds of some plant species, they also produced a great deal of fruit and seed waste for others.
Social influences on sexual maturation of female Saguinus oedipus oedipus
Authors: Tardif S. D. 
Published: June 2005

AbstractThe hypothesis tested was that Saguinus oedipus oedipus females housed with adult males would mature, sexually, at an earlier age than females remaining in their natal family groups. Six females were housed with strange, unrelated males. Five females remained in their natal groups. Blood samples were taken twice weekly, and the plasma was assayed for progesterone. Sexual maturation was operationally defined as that age at which plasma progesterone levels became consistently detectable. Females housing with males did mature at an earlier age than females remaining in their natal groups. In addition, it was noted that the presence or absence of a healthy, reproductive mother in the natal group was not related to the daughter's maturation age. However, whether the natal group, as a whole, inhibited maturation of young females, or an unrelated male accelerated maturation, or both, remains unknown.
Low potency of intact male rhesus monkeys after long‐term visual contact with their female partners
Authors: Zumpe Doris , Michael Richard P. 
Published: June 2005

AbstractWe have examined the possibility that prolonged visual contact between future sexual partners, in the absence of any direct sexual contact and mating activity, is sufficient to produce the familiar‐female phenomenon and is associated loss of male potency. For 1 year, 32 intact, feral‐reared male rhesus monkeys were housed so that 14 males were in constant visual contact with their four future testing females, and 18 of the males were without any visual contact with females. After 1 year, each male was then tested once with each ovariectomized, estrogen‐treated female (128 tests). Males in the group having prolonged prior visual contact (group II) were significantly less potent than males without prior visual contact (group I), and this difference was not related to plasma testosterone levels, prior history, time since capture, or presumed age. Group II males had fewer ejaculations during tests and ejaculated with fewer partners, and this appeared to be because they required significantly more stimulation (mounting and thrusting) to reach ejaculation. The data suggested that the familiar‐partner phenomenon was not restricted to the male and was associated with increased social affinity and decreased agonistic tension between partners. Under natural conditions, the phenomenon may encourage troop transfers and outbreeding, and in laboratory studies, prior visual contact between testing partners should be regarded as a potentially uncontrolled source of variation.
Female mate choice in vervet monkeys (Cercopithecus aethiops sabaeus)
Authors: Keddy Anne C. 
Published: June 2005

AbstractFemale mate choice was examined in a captive group of vervet monkeys (Cercopithecus aethiops sabaeus). Male‐female interactions were examined under both dyadic and group conditions to determine whether females mate with different males under the two conditions. Results showed that all females preferred to mate with the alpha male under both dyadic and group conditions. Alpha females, however, were more successful than subordinate females in rejecting the sexual solicitations of subordinate males. Thus female dominance status played an important role in determining the degree to which females exercised mate choice.
Influence of acute stress and the adrenal axis on regulation of LH and testosterone in the male rhesus monkey (Macaca mulatta)
Authors: Hayashi Kevin T. , Moberg Gary P. 
Published: June 2005

AbstractIn order to determine the mechanism by which stress may affect the secretion and function of luteinizing hormone (LH) in primates, the response of the adrenal and gonadal axes was followed in male rhesus monkeys during brief restraint in primate chairs and during various hormone treatments. To further assess the responsiveness of the gonadal axis, gonadotropin releasing hormone (GnRH) was administered during the experiments. Corticosteroid levels were elevated throughout the first restraint trial as compared to those in subsequent trials. LH was elevated in the first sample of the first trial as compared to that in the following trials. The responses of LH to GnRH were equivalent in all trials, while the testosterone response to GnRH was attenuated in the first trial. A single injection of adrenocorti‐cotropin (ACTH, 40 IU), while increasing circulating corticosteroids similarly to that observed during the first restraint trial, failed to cause an acute initial release of LH. However, ACTH did lower the testosterone response to GnRH. Following 5 days of ACTH treatment (40 IU twice daily), basal LH was suppressed, and the testosterone response to GnRH was decreased. Following 5 days of cortisol injections (100 mg twice daily), basal LH and testosterone were suppressed, but again only the testosterone response to GnRH was attenuated. Acute restraint stress, acting by some mechanism other than the activation of adrenal axis, stimulates a transient release of LH. While the stress‐stimulated release of corticosteroids failed to affect the LH response following GnRH administration, it did act directly on the testes to prevent the normal release of testosterone. Finally, chronic elevation of corticosteroids, produced by ACTH or cortisol administration, suppressed basal serum LH and attenuated the response of testosterone to GnRH.
Aspects of fight interference in free‐ranging and compound‐dwelling rhesus macaques (Macaca mulatta)
Authors: Kaplan Jay R. , Chikazawa Dennis K. , Manuck Stephen B. 
Published: June 2005

AbstractPatterns of fight interference (agonistic aiding) were compared among three groups of rhesus monkeys (Macaca mulatta) living in two settings: (1) two groups at Cayo Santiago (Caribbean Primate Center); and (2) one group at the Yerkes Regional Primate Research Center (YRPRC). A total of 1,227 interference episodes were recorded in 1,650 hours of observation. The only significant intergroup difference was the increased tendency of males at YRPRC to aid aggressors rather than victims. Among other findings, females aided relatives, interfered against target animals dominant to themselves, aided juveniles, and aided victims more consistently and frequently than did males. Importantly, female interference became more male‐like in pattern when aid was given to nonrelatives. Neither the dominant males nor males in general displayed a unique or consistent tendency to interfere in fights in a manner which could be interpreted as controlling aggression. The males' interference patterns also did not suggest they were forming coalitions to either attain or defend status rankings. It is concluded that, overall, observations of compound‐dwelling and free‐ranging rhesus monkeys reveal similar relationships. Further, while female rhesus monkeys interfered in fights in a manner consistent with the control of aggression and protection of kin, the motives of male interferers remain unknown; however, their behavior is consistent with the hypothesis that they were reducing intermale tensions while, at the same time, minimizing physical risk.
Do line‐transect surveys systematically underestimate primate densities in logged forests?
Authors: Skorupa Joseph P. 
Published: June 2005

AbstractThe rate at which social groups of primates are encountered in disturbed rain forest may be biased relative to undisturbed rain forest. A recently reported case study revealed a 25% reduction in postlogging raw encounter rates even though the true density of primates remained at the prelogging level. If biased raw encounter rates are typical of disturbed forests, and if they translate into equally biased line‐transect density estimates, results of many comparative surveys might prove misleading (ie, apparent declines of primates in disturbed forest may not be real). Here a set of line‐transect density estimates from logged forest are tested for systematic bias by comparing them to range‐mapping density estimates, and the response of a Fourier series detectability function to several hypothetical patterns of bias in raw encounter rates is illustrated. Tests of line‐transect density estimates from logged forest provide no evidence of systematic bias. The Fourier series results suggest that biased raw encounter rates may often be ameliorated by line‐transect density estimators. Available evidence suggests that line‐transect density estimates or similarly transformed encounter rates usually provide reliable comparative results within the limits of a particular study's resolution. In contrast, conclusions drawn directly from comparative raw encounter rates (without transforming them into density estimates) are more prone to error.
Fatal intragroup kidnapping in yellow baboons
Authors: Shopland Jennifer M. , Altmann Jeanne 
Published: June 2005

AbstractThe fatal kidnapping of a 5‐day‐old baboon (Papio cynocephalus) in Amboseli National Park, Kenya, is described. Although pulling and rough handling of primate infants by nonmothers are frequently observed, records of fatal intragroup kidnappings are rare. In the instance described here, the mother, a healthy, primiparous female, did not retrieve the infant from the kidnapper, a higher‐ranking juvenile female of the same group, until he died 3 days later, presumably from starvation or dehydration. This incident is compared with other fatal intragroup kidnappings in nonhuman primates and related to adaptive interpretations.
Description of ultrasonic vocalizations of the mouse lemur (Microcebus murinus) and the fat‐tailed dwarf lemur (Cheirogaleus medius)
Authors: Cherry James A. , Izard M. Kay , Simons Elwyn L. 
Published: June 2005

AbstractUltrasonic (>20 kHz) vocalizations were recorded from two species of prosimian primates, Microcebus murinus and Cheirogaleus medius. Three types of ultrasonic calls were emitted by isolated or paired M. murinus: 1) “chirps,” short‐duration (30 msec) calls with a sharp onset at 40 kHz followed by rapid and steep declines in frequency and intensity; 2) “twitters,” characterized by a brief pulse at 25 kHz prior to the onset of repeating, frequency‐modulated units; and 3) “long whistles,” monotone signals with a frequency of 20 kHz. Partially ultrasonic “whines” were recorded from C. medius during interactions between mothers and infants. These calls began with a short, high‐intensity component at 25 kHz and then dropped gradually in frequency before leveling off at 15 kHz. Study of the acoustic behavior and the structure of vocalizations in these species may lead to a better understanding of animal communication at high frequencies.
Adrenal myelolipoma in the cottontop tamarin (Saguinus o. oedipus)
Authors: Pearson G. R. , Kirkwood J. K. , Scullion F. 
Published: June 2005

AbstractTwo cases of myelolipoma in the cottontop tamarin (Saguinus o. oedipus) were found unequivocally within the adrenal gland, supporting an earlier suggestion that the adrenal gland was the possible origin of a juxtarenal myelolipoma in the same species. In the present study a 30‐mm‐diameter myelolipoma was present in the adrenal gland in case 1, whereas in case 2 the myelolipoma was only detected on histological examination. In case 1, changes in the adrenal gland were considered to be of minor clinical significance, whereas in case 2 the myelolipoma was an incidental finding.
Reactions of nuclear‐family–reared rhesus macaques to the births of younger siblings
Authors: DiGregorio Gayle , Suomi Stephen J. , Eisele Carole E. , Chapman Sharon A. 
Published: June 2005

AbstractA group of juvenile rhesus macaques (Macaca mulatta) living in a nuclear‐family laboratory environment was studied to determine their responses to the births of siblings. The frequencies of interactions with family members (mothers, fathers, and new siblings) and nonfamily (peers, unrelated infants, and unrelated adults) were studied over both the year preceding and the year following sibling birth. The frequencies of specific behaviors in each of those interactions and the frequencies of interactions in each area of the nuclear‐family unit (home cage, play area, or other families' cage) were also examined. After new siblings arrived, several measures of interactions with mothers, fathers, and new siblings increased significantly; by contrast interactions with peers decreased substantially over the post‐birth year. Although the frequency of interactions in home cages remained stable over the 2‐year period, interactions outside of the subjects' home cages decreased significantly after siblings were born. An additional subject group whose mothers became pregnant but failed to deliver viable offspring showed no significant changes in total levels of interactions with peers; they did, however, exhibit increases in some interactions with unrelated infants and adults. Female juveniles interacted with new siblings significantly more often than did males when siblings were less than 6 months old, but as siblings grew older (6–12 months), females' levels of interaction with them fell to a level equal to that of males. In the nuclear‐family social structure, the birth of a sibling resulted in an increased emphasis on family interactions at the expense of peer interactions.
Terrestrial locomotion and back anatomy in vervets (Cercopithecus aethiops) and patas monkeys (Erythrocebus patas)
Authors: Hurov Jack R. 
Published: June 2005

AbstractThis comparative study addressed the problem of relationships between locomotor behavior and back anatomy in the cursorial monkeys, Cercopithecus aethiops and Erythrocebus patas. Analysis of cine‐film revealed that patas and vervet monkeys differed significantly in the degree to which they used their backs to increase stride length during galloping. C. aethiops showed increased ranges of sagittal back motion as galloping speed increased almost fivefold; E. patas failed to show significant increases in amplitudes of sagittal back motion despite a five‐to‐sixfold increase in galloping speed. Comparison of epaxial anatomies demonstrated conservative morphologic features which could not be used to explain interspecific differences in sagittal movement patterns of the back. However, when compared to patas monkeys, vervets possessed thicker intervertebral discs, relative to vertebral bone, and reduced dorsoventral diameters of their theracic cages. These anatomic differences were explained on the basis of theoretical bio‐mechanics as being necessary structural prerequisites for enhancing sagittal back mobility. The present analysis of locomotor behavior involving the back and epaxial morphologies was integrated with observations of interspecific differences in limb anatomies and comparative anatomic studies of other mammalian species to develop a general description of strategies used by patas and vervet monkeys to increase stride length during galloping.
Scratching, dominance, tension, and displacement in male baboons
Authors: Easley Stephen Phillip , Coelho Anthony M. , Taylor Linda L. 
Published: June 2005

AbstractThis paper reports a study designed to test the hypothesis that a relationship exists among dominance rank, tension, and scratch behaviors in anubis baboons (Papio cynocephalus anubis). Our study was conducted on two groups of male baboons, each containing eight unrelated individuals who were approximately 6 years of age and who shared common rearing histories. Focal animal sampling was used to collect behavioral data. Hand scratching, foot scratching, avoid, tension, allogrooming, autogrooming, and manipulation were measured as acts performed per hour of sampling. Dominance matrices were constructed based on net difference of avoid behavior performed and received (adjusted for time sampled). Individual status ranks were grouped into two status classes, high and low. Analysis of variance models demonstrated significant differences in the performance rate of scratching behaviors by dominance rank class, as well as differences in scratching performance by tension class. Individuals in the high status class had significantly higher rates of total scratching, hand scratching, foot scratching, and tension behavior performance than their counterparts in the low status class. No significant difference was found between status classes or tension classes for performance rate of allogrooming, autogrooming, or manipulation behavior. The frequency of scratching and general level of activity were not significantly correlated. The results are interpreted to indicate the possibility that scratching may function as a displacement behavior, which subjectively appears to communicate heightened frustration, anxiety, or arousal.
Prevalence of glucose intolerance in free‐ranging Macaca fascicularis of Mauritius
Authors: Dunaif Andrea , Tattersall Ian 
Published: June 2005

AbstractOral glucose tolerance tests (OGTTs) were carried out on 30 free‐ranging long‐tailed macaques (Macaca fascicularis) on the island of Mauritius, following the suggestion that severe glucose intolerance and diabetes mellitus might be prevalent in this macaque population. OGTTs revealed no evidence of frank diabetes mellitus in the sample. However, 13% of individuals showed impaired glucose tolerance, with preserved insulin secretion, suggesting the presence of the target tissue resistance to insulin characteristic of human noninsulin‐dependent diabetes mellitus (NIDDM). The macaques with impaired glucose tolerance were neither obese nor aged. Glucose levels at all time points of the OGTT in normal macaques in our free‐ranging sample were lower than reported in captive populations, perhaps due to greater physical activity. Our observations demonstrate that a genetic predisposition to glucose intolerance does exist in M. fascicularis, and that this condition, well documented in laboratory macaques, is not simply an artifact of captivity.
Wounding patterns in three species of captive macaques
Authors: Ruehlmann Thomas E. , Bernstein Irwin S. , Gordon Thomas P. , Balcaen Peter 
Published: June 2005

AbstractThe incidence of wounding in captive groups of rhesus (Macaca mulatta), pigtail (M. nemestrina), and stumptail (M. arctoides) macaques was studied for 21 months. Groups were monitored daily for evidence of wounding. Wounded animals were captured, treated by veterinary staff, and returned following recovery. Records were kept on the age, sex, and species of the recipient, along with the type and location of wound. In each species of macaque, adult males incurred the highest frequency of wounds and multiple wounds of any age‐sex class. This contrasted with previously reported behavioral data indicating low frequencies of aggression received by adult males, especially contact aggression and bites. These discrepancies indicate wounding frequencies do not necessarily correspond with behavioral measures of aggression. Inhibition of aggression directed toward infants and the selective avoidance of bites directed to vital body regions were presented as possible mechanisms that modify intragroup aggression. Increased wounding in the birth season under captive conditions suggests that the pattern of increased wounding reported during the breeding season under freeranging conditions may reflect xenophobic responses to immigrating males, rather than direct male‐male competition for estrous females.