bluuebunny/crossref_metadata_2025_split huggingface dataset:
Semen characteristics of the adult male chimpanzee (Pan troglodytes)
Authors: Gould Kenneth G. , Young Leona G. , Smithwick Eleanor B. , Phythyon Sarah R. 
Published: June 2005

AbstractThe chimpanzee, because of its similarities to the human, is especially valuable in studies of reproductive function. However, relatively little is known about the physiology of reproduction in the adult male chimpanzee. This study provides, for five adult male chimpanzees, baseline values for testicular volume without and with pressure and for cellular and biochemical characteristics of ejaculates collected by artificial vagina (AV). There was no correlation between body weight and testicular volume measured without or with pressure. The ratios of mean testicular volume without and with pressure were not statistically different among animals. Statistical analysis of penetration of denuded hamster oocytes by ejaculated chimpanzee sperm revealed no correlations between sperm count and percentage of eggs penetrated. There was significant variability in concentrations of protein and fructose and in activities of alpha‐glucosidase and acid phosphatase among samples from different animals. Computer‐assisted motion analysis (CAMA) of sperm provided baseline data on motion parameters necessary for future evaluation of this technique for semen analysis in the chimpanzee. The level of demonstrated inter‐animal variation mandates use of each animal as its own control for studies on normal and altered reproductive function. © 1993 Wiley‐Liss, Inc.
Midazolam as an effective intravenous adjuvant to prolonged ketamine sedation in young rhesus (Macaca mulatta) and Vervet (Cercopithecus aethiops sabaeus) monkeys: A preliminary report
Authors: Jacobs Bob , Harris Gregory C. , Allada Vivekanand , Chugani Harry T. , Pollack Deborah B. , Raleigh Michael J. 
Published: June 2005

AbstractThe present study investigated a recently developed benzodiazepine, midazolam, as an intravenous adjuvant to ketamine in infant monkeys undergoing prolonged sedation during positron emission tomography of the brain and heart. Subjects were two rhesus macaque (Macaca mulatta) and ten vervet monkeys (Cercopithecus aethiops sabaeus) ranging in age from 26 to 260 days. Midazolam was an effective intravenous adjuvant to ketamine. This treatment regime resulted in complete immobilization of the animals. Ketamine infusion rates did not vary significantly with age for either species. Sensitivity to midazolam appeared to be age‐dependent in vervets because significantly lower dose rates were sufficient to maintain anesthesia in older animals. For rhesus monkeys, midazolam dose rates decreased until approximately 4 months of age, and increased gradually thereafter. © 1993 Wiley‐Liss, Inc.
Inter‐group encounters and female transfer in mountain gorillas: Influence of group composition on male behavior
Authors: Sicotte Pascale 
Published: June 2005

AbstractThis paper examines the behaviors used by male gorillas (G. gorilla beringei) to influence female choice during inter‐group encounters. Encounters are related to the acquisition of females rather than to the defense of a group's range. Data on 58 independent encounters confirms that encounters are generally aggressive, but that contact aggression is less frequent than previously reported. A high number of potential migrants in one of the groups involved, rather than the newness of either group, predicts the likelihood of contact aggression between males. Encounters with a newly formed unit last longer than encounters involving established groups. Male herding serves to prevent female transfer. Females without dependent offspring are more likely than others to be herded. Proceptive females are the target of herding more often than non‐proceptive cycling females. Groups where herding has been observed are more likely to be newly formed, and they include significantly more males. This last result confirms that there are advantages to male cooperation in gorillas. It also raises the question of why such cooperation does not occur more often. © 1993 Wiley‐Liss, Inc.
Population dynamics of Macaca sylvanus in Algeria: An 8‐year study
Authors: Ménard Nelly , Vallet Dominique 
Published: June 2005

AbstractThe demography and dynamics of two groups, one living in an evergreen cedar‐oak forest (Tigounatine) and the other, in a deciduous oak forest (Akfadou) in Algeria, were studied from 1982 to 1990. Group size fell within the range of other wild groups except for the Tigounatine group when it reached 88 individuals before splitting into three new independent groups. The structure of the studied groups, except one which was temporarily “one male,” was comparable to that of other groups of Barbary macaques. There were 43–50% of immatures on average depending on the group. The sex ratio (M:F) of the sexually mature animals was relatively balanced (1:0.9–1.2). The mean age of primiparous females was 5.5 years in Tigounatine and 5.3 in Akfadou; the rate of reproduction of sexually mature females was 0.56 and 0.63, respectively, while the infant mortality rate was 0.23 and 0.38, respectively. Great interannual variations occurred at both sites. The differences between natality and mortality induced a higher intrinsic mean annual increase for the Tigounatine group (14.6%) than for the Akfadou group (4.8%). The rate of intergroup transfers was not correlated with the increase in group size. Integration of male immigrants did not lead to the departure of resident males. Conversely, fission process promoted a substantial increase in the number of transfers in Tigounatine.The period presenting the greatest risk of infant mortality was the summer dry period, in both habitats. Wide interannual variations occurred in the availability of two staple foods for monkeys: caterpillars and acorns. The cumulative effects of a low acorn supply during the gestation period (autumn) and a low caterpillar supply during the beginning of the following nursing period (spring) led to a temporary increase in infant mortality. © 1993 Wiley‐Liss, Inc.
Infant survival and number of helpers in captive groups of common marmosets (Callithrix jacchus)
Authors: Rothe H. , Koenig A. , Darms K. 
Published: June 2005

AbstractIn a colony of captive marmoset monkeys (Callithrix jacchus), the survival rate of infants up to the age of 90 days after birth was analyzed with special reference to the number of members in the group. The number of group members (newborns excluded) varied between two (parents only) and 18 (parents plus non‐reproductive helpers); the number of adult group members varied between two and 15. Five hundred ninety‐two live‐born, parent‐reared infants of 263 litters from 56 breeding females were included in the analysis. The greatest reproductive success was observed in groups of ten to 11 members or four to five adults, including the parents. However, the survival rate was fairly constant over group size at approximately 80% of an expected maximum value and no significant correlation was observed between the total number of group members and infant survival rate, or between the number of adult members and infant survival. While helpers may be necessary to increase the survival rate of infants in wild groups, help of non‐reproductive animals is not required in captivity, where energetic demands are comparatively low and ecological constraints absent. Under laboratory conditions the parents' skill in infant handling and the mother's physical condition, i.e., the ability to provide enough milk for the infants, is likely to be the most important factor for infant survival. © 1993 Wiley‐Liss, Inc.
Genetic characterization of parental cell lines and biochemical analysis of somatic cell hybrids between mouse (RAG) cells and fibroblasts of Ateles paniscus chamek (primates, platyrrhini)
Authors: Seuánez Héctor N. , Alves Gilda , O'brien Stephen J. 
Published: June 2005

AbstractMouse (RAG) cells, (deficient in hypoxanthine‐phosphoribosyl‐transferase), and Ateles paniscus chamek primary fibroblasts were used in fusion experiments to generate somatic cell hybrids. Both parental cell lines were genetically characterized by karyological and biochemical analyses with 27 isozyme systems. These procedures were useful for monitoring primate chromosome segregation in somatic cell hybrids, for detecting chromosome rearrangements of primate chromosomes, and for identifying individual primate chromosomes.These characterizations are necessary to distinguish between different hybrid cell lines and to generate a panel for gene mapping studies. This is achieved by selecting cell lines that segregate different sets of relatively few primate isozymes and chromosomes. Conversely, we eliminated hybrid cell lines either showing: (1) rearrangements between primate and mouse chromosomes, (2) extensive rearrangements of primate chromosomes, or (3) a large number of primate biochemical markers. © 1993 Wiley‐Liss, Inc.
Composition of the diet of chimpanzees and comparisons with that of sympatric lowland gorillas in the lopé reserve, gabon
Authors: Tutin Caroline E. G. , Fernandez Michel 
Published: June 2005

AbstractOver an eight‐year period, a total of 174 food items were recorded for chimpanzees (Pan t. troglodytes) in the Lopé Reserve in central Gabon. Plant foods, principally fruit, dominated the diet but insects were eaten regularly, and predation on at least three species of mammal occurred infrequently. The diversity of the vegetative component of the diet (leaves, stems, and bark) was probably underestimated by fecal analysis. Comparison of chimpanzee diet at Lopé with that of sympatric lowland gorillas showed the majority of foods were eaten by both species (73% of chimpanzee food items and 57% of gorilla food items). The overlap of fruit species was greater (82% and 79%, respectively) than that of other food classes. Both chimpanzees and gorillas harvested the majority of their plant foods arboreally (76% and 69%, respectively). The high degree of dietary overlap suggested that ecological competition between these two closely related species might exist. Few overt signs of competition for food either between or within species were observed but when fruit was scarce, the diets of the two species showed greatest divergence. The major differences between chimpanzee and gorilla diet at Lopé were the larger quantities of vegetative foods regularly eaten by gorillas and their ability to resort to a diet dominated by vegetative foods when fruit was scarce. In these respects, chimpanzees at Lopé resembled populations of Pan troglodytes studied elsewhere while Lopé gorillas resembled mountain gorillas (Gorilla g. beringei) and bonobos (Pan paniscus) in their greater dependence on vegetative foods. © 1993 Wiley‐Liss, Inc.
Photopigments underlying color vision in ringtail lemurs (Lemur catta) and brown lemurs (Eulemur fulvus)
Authors: Jacobs Gerald H. , Deegan Jess F. 
Published: June 2005

AbstractA recent examination of color vision in the ringtail lemur produced evidence that these prosimians could make color discriminations consistent with a diagnosis of trichromatic color vision. However, it was unclear if this behavior reflected the presence of three classes of cone or whether lemurs might be able to utilize signals from rods in conjunction with those from only two classes of cone. To resolve that issue, spectral sensitivity functions were obtained from ringtail lemurs (Lemur catta) and brown lemurs (Eulemur fulvus) using a noninvasive electrophysiological procedure, electroretinographic flicker photometry. Results from experiments involving chromatic adaptation indicate that these lemurs routinely have only a single class of cone photopigment in the middle to long wavelengths (peak sensitivity of about 545 nm); they also have a short‐wavelengthsensitive cone pigment with peak of about 437 nm. The earlier behavioral results are suggested to have resulted from the ability of lemurs to jointly utilize signals from rods and cones. The cone pigment complements of these lemurs differ distinctly from those seen among the anthropoids. © 1993 Wiley‐Liss, Inc.
Acoustic analysis of wild chimpanzee pant hoots: Do Kibale Forest chimpanzees have an acoustically distinct food arrival pant hoot?
Authors: Clark Adam P. , Wrangham Richard W. 
Published: June 2005

AbstractRecordings were made of 193 pant hoots given by 6 adult males during ad lib sampling over a 16‐month period in 1988 and 1989. The presence or absence of a let‐down phase, and acoustic measures of the let‐down and climax phases of the calls, were compared for different call contexts to determine if an acoustically distinct pant hoot was given uniquely upon arrival at fruiting trees. The greatest proportion of pant hoots with a let‐down (LD pant hoots) occurred immediately upon arrival at fruiting trees. However, LD pant hoots also occurred at other times during feeding bouts. The frequency and duration of the first exhaled element of 19 letdown phases were measured, and four measures were made on the highest pitched element of 49 climax phases: duration, maximum and minimum frequencies, and average frequency. No differences were found in these acoustic measures that distinguished calls given immediately upon arrival at a food tree from calls given later during feeding bouts. Thus no evidence was found that an acoustically distinct pant hoot was given uniquely upon arrival at fruiting trees. However, the analyses did suggest that identifiable pant hoot variants are given in different social contexts. The proportion of LD pant hoots decreased in more interactive social contexts, and other acoustic features may be available to distinguish this pant hoot variant at long distances. We suggest that different pant hoot variants might broadcast information specific to social, as opposed to ecological, context. © 1993 Wiley‐Liss, Inc.
Rank differences in the production of vocalizations by wild chimpanzees as a function of social context
Authors: Clark Adam P. 
Published: June 2005

AbstractRank differences in the production of vocalizations by wild, semihabituated, unprovisioned chimpanzees were investigated during a 10‐month study in the Kibale Forest, Uganda. Vocalization rates were calculated from data collected during 230 hours of focal‐animal sampling on adult females, adult males, and subadult males. Rates were calculated according to whether individuals were alone, with adult females only, or in mixed parties, and the results were compared with published data collected at the Gombe provisioning area. Adult females and low‐ranking adult and sub‐adult males were generally quiet except when they were in mixed parties, whereas high‐ranking males vocalized in all social contexts. These results were in partial contrast to data collected at Gombe, which indicated that vocal production was similar across all age and sex classes. Vocal production at Gombe did, however, resemble that from mixed parties at Kibale, suggesting that the provisioning area at Gombe was comparable to a natural socioecological context occurring at large fruiting trees. It is suggested that low‐ranking chimpanzees refrain from loud vocalizing when they are alone or with females only in order to avoid attracting feeding competition and/or potentially aggressive males. These individuals may vocalize when they are associating with high‐ranking males in order to advertise the presence of large parties and to deter other individuals from joining them. The use of loud, interparty calls by high‐ranking males, when alone or with others, is consistent with the greater sociality of adult male chimpanzees. Loud calling might be advantageous for adult males in attracting mates or allies. © 1993 Wiley‐Liss, Inc.
Field Techniques for Monitoring Cotton‐Top Tamarins (Saguinus oedipus oedipus) in Colombia
Authors: Savage Anne , Giraldo L. Humberto , Sblumer Evan , Soto Luis H. , Burger William , Snowdon Charles T. 
Published: June 2005

AbstractWe present reliable field techniques for capturing, anesthetizing, and Iidentifying individual cotton‐top tamarins (Saguinus oedipus oedipus). A new technique is presented for radio‐tracking small bodied primates. A backpack‐style harness was designed to carry a transmitter. This system appears effective in minimizing potential injury and does not appear to interfere with the normal behavior of the animal. © 1993 Wiley‐Liss, Inc.
Sex differences in adolescent rhesus monkey (Macaca mulatta) Behavior
Authors: Bernstein Irwin S. , Judge Peter G. , Ruehlmann Thomas E. 
Published: June 2005

AbstractSex differences in the behavior of 2.5‐ to 4.5‐year‐old rhesus monkeys, living in two social groups approximating natural compositions, were studied over a period of 3 years. Both sexes interacted significantly more often with members of their own sex in agonistic and affiliative interactions even when total rates and durations for male and female subjects did not differ. Strong sexual segregation was also seen in proximity, nonspecific contact, and huddling partners. Males were more involved in play and sex than were females and engaged in these activities primarily with other males. Females did more grooming than males, but groomed both male and female partners. Females also appeared to interact with a wider age range of partners than did males. Although total participation in aggressive interactions did not differ between the two sexes, females used more active forms of agonistic expression than did males. These differences in the behavior of adolescent rhesus are hypothesized to lead to social bonding among adolescent males, while females remain bonded to their matri‐lines, including younger males and some fully adult males associated with matrilineal relatives. Adolescent males emigrate from their natal groups but retain sociality and bond to males and females in new groups as they become adult. © 1993 Wiley‐Liss, Inc.
Food sharing in lion tamarins: Tests of three hypotheses
Authors: Price Eluned C. , Feistner Anna T. C. 
Published: June 2005

AbstractInfant marmosets and tamarins (Callitrichidae) frequently receive food from older group members. Three possible functions of food sharing in lion tamarins were examined experimentally. The first hypothesis, that food sharing ensures that infants receive sufficient food even if it is difficult for them to acquire it themselves, was tested by varying the ease with which infants could reach a food source. When access to food was restricted, infants fed themselves less, received more food from others, and had a higher success rate in begging attempts. The second hypothesis, that food sharing helps teach infants an appropriate diet, was tested by presenting fruits that were novel to infants. Although infants fed themselves less under these conditions, adults were less likely to share novel foods than familiar foods. The final experiment compared food sharing when food was abundant with behavior when food items were presented singly. Infants fed themselves less and received more food from others when food items were rare. These results suggest that food sharing in lion tamarins helps to ensure that infants receive adequate amounts of food which is difficult to locate or acquire, but that it is not involved in teaching infants which foods they should eat. © 1993 Wiley‐Liss, Inc.
How to obtain individual urine samples from undisturbed marmoset families
Authors: Anzenberger G. , Gossweiler H. 
Published: June 2005

AbstractAn apparatus and a method are described, which allow simultaneous urine collection from all individual members of undisturbed marmoset families. The monkeys have been trained, after leaving their sleeping box, to enter single adjacent compartments where they are rewarded. There the monkeys micturate within minutes and the clean urine runs directly into cryotubes. These simultaneously collected urine samples open up the opportunity for investigation of the relationship between endocrine function and behavioral dynamics within entire marmoset groups. © 1993 Wiley‐Liss, Inc.
Complex leaf‐gathering skills of mountain gorillas (Gorilla g. beringei): Variability and standardization
Authors: Byrne Richard W. , Byrne Jennifer M. E. 
Published: June 2005

AbstractThe skills that mountain gorillas use to deal with the stings, tiny hooks, and spines protecting common plant leaves in their diet were examined for variation within and between animals. Many elements of uni‐ and bimanual performance were identified, often involving delicate precision and coordination, and varying idiosyncratically, erch individual having a different set of preferred elements. Many of these elements are functionally equivalent, and all but one weaned animals showed full processing capability; the history of the one exception suggests that early experience with the task may be important. Gorillas' idiosyncrasy in manual skill elements is entirely consistent with trial‐and‐error learning at this level. By contrast, each individual uses very few techniques (structured sequences of elements) for most processing, and these techniques are the same across the population. Where animals deviate from this generalization, they largely employ the simpler technique normally used for undefended leaves. Lateralization increases from start to finish, consistent with a logical structure in which each stage has a laterality bias and each stage is sequentially dependent on the last. Variations from their commonest, techniques occur in all animals (on average, about nine variant techniques were recorded from each animal). The repertoire of techniques increases significantly with age, whereas the repertoire of elements does not. This points to an initial reliance on a single logical structuring that is well established by weaning (about 3.5 years), with subsequent development of the ability to vary the technique used so as to take advantage of variations in the environment. Standardization of logical organization, despite variability between different animals in individual elements and behavioral laterality, suggests that the logical ordering of elements and the interrelationships of processing stages is copied by program‐level imitation. © 1993 Wiley‐Liss, Inc.
Range use of the forest chimpanzees of Kibale: Implications for the understanding of chimpanzee social organization
Authors: Chapman Colin A. , Wrangham Richard W. 
Published: June 2005

AbstractWe contrast the range use patterns of male and female chimpanzees (Pan troglodytes) based on repeated sightings over three years of 19 individuals in the Kanyawara community of Kibale Forest Reserve, Uganda. Depending on how home range size was calculated, male chimpanzees used an area that was 1.5 to 2 times greater than that of females. There was no difference between the sexes in whether their home ranges were used in a clumped or uniform fashion. However, males were more likely to be seen in boundary areas than females. These results are discussed in light of previously proposed models of chimpanzee social organization. It is concluded that the scenario in which females have smaller core areas within the defended home range of the males is most strongly supported by the range use patterns observed in Kibale chimpanzees. © 1993 Wiley‐Liss, Inc.