共查询到20条相似文献，搜索用时 15 毫秒
1.
Tillmann Fünfstück Mimi Arandjelovic David B. Morgan Crickette Sanz Thomas Breuer Emma J. Stokes Patricia Reed Sarah H. Olson Ken Cameron Alain Ondzie Martine Peeters Hjalmar S. Kühl Chloe Cipolletta Angelique Todd Shelly Masi Diane M. Doran‐Sheehy Brenda J. Bradley Linda Vigilant 《American journal of primatology》2014,76(9):868-878
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Melissa J. Remis 《American journal of primatology》1997,43(2):111-133
The ranging and grouping patterns of a gorilla group were studied during 27 months from 1990–1992 at the Bai Hokou study site, Central African Republic. The study group ranged far daily (average = 2.3 km/day) and had a large home range (22.9 km2), relative to mountain gorillas, and ranging patterns differed between years. During 1990–1992, the bimale study group foraged less cohesively and had more flexible grouping patterns than mountain gorillas. The study group sometimes split into two distinct foraging subgroups, each led by a silverback, and these subgroups occasionally slept apart (mean = 950 m apart). Lowland gorillas rely on many of the same fruit resources as sympatric chimpanzees, and under certain demographic situations gorillas, like sympatric chimpanzees, may adapt their foraging group size to reduce intragroup feeding competition. However, the fiber content of the lowland gorilla diet likely relaxes constraints on foraging party size and facilitates group cohesion relative to chimpanzees. Am. J. Primatol. 43:111–133, 1997. © 1997 Wiley-Liss, Inc. 相似文献
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The successful management of a captive gorilla population often necessitates the hand‐rearing of infants and their subsequent re‐integration into social groups of conspecifics. In the present study we quantified the changes in nearest‐neighbor associations in a group consisting of a silverback male, three adult females, and two sub‐adult females after the introduction of five hand‐reared infants. Additionally, we examined the associations among kin and non‐kin group members to determine whether genetic relatedness was a factor influencing the integration of the infants into the group and the subsequent patterns of association among infants and adults. Results showed that after the introduction, the silverback male spent >60% of his time in close proximity to an infant and 10% of his time within a “cluster” of infants. There was a significant change in a female's nearest‐neighbor associations; however, the change did not include an infant. The most significant finding among infants was a strong bias by each to associate with another infant. When the infants associated with an adult, three of the five associated most with the silverback male (P < 0.001), whereas the other two infants distributed their time among all the adults. The most significant change in behavior patterns was exhibited by one of the sub‐adult females who displayed parental behaviors 18% of the time compared to <1% for all other females. Adults and one sub‐adult female associated significantly more often with related infants compared to unrelated infants (P < 0.025), and the infants showed a bias to associate with another related infant (P < 0.0001). Results of an infant's association with an adult showed that three of the five infants preferred to associate with a related adult (P < 0.0001). An individual's age, sex, and behavioral profile may have also influenced association patterns among group members. These findings lend strong support to the importance of peer groups and the presence of a silverback male for facilitating the integration of hand‐reared infants into established adult groups. Zoo Biol 18:261–278, 1999. © 1999 Wiley‐Liss, Inc. 相似文献
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Habituation of western gorillas to human presence is generally an expensive, lengthy and difficult process. Here we describe the habituation process for two groups of western gorillas at the Mondika Research Center, with the hope that the lessons we learned will facilitate future gorilla studies. We expand upon earlier studies by describing the process through complete habituation for both males and females, and for more than one group. The major obstacle to habituation was developing sufficient tracking skills to follow gorilla trail on a daily basis. Once this was achieved, the silverback became semi-habituated (i.e. ignoring human presence during half of contacts) within a year, although the majority of group females continued to avoid humans. As female presence at contacts increased, a period of male recidivism followed, requiring an additional year before his complete habituation was reached. Habituating the females took longer than the male, but we found, contrary to earlier studies, that it consisted of the same stages, including avoidance, aggression, and curiosity before habituation. We compare results between groups and across sites and discuss how factors such as tracking abilities, group size and cohesion, population density and home range overlap, and the manner of approaching gorillas during contacts influence the habituation process. 相似文献
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Rebecca N. Lewis Yu-Mei Chang Amanda Ferguson Tracey Lee Lisa Clifforde Siobhan M. Abeyesinghe 《Zoo biology》2020,39(5):283-296
Primates, especially apes, are popular with the public, often attracting large crowds. These crowds could cause behavioral change in captive primates, whether positive, neutral, or negative. We examined the impact of visitors on the behavior of six western lowland gorillas (Gorilla gorilla gorilla), observing the troop over 6 weeks during high season (4.5 hr/day, 35 days, May–July 2016). We used focal scan sampling to determine activity budget and enclosure usage, and focal continuous sampling to identify bouts of anxiety-related behavior (visitor-directed vigilance, self-scratching, and aggression). Both daily zoo-entry numbers (VGATE) and instantaneous crowds at the exhibit (VDENSITY) were measured. Overall, VGATE had little effect across behaviors. However, consistent with the more acute time frame of measurement, VDENSITY was a better predictor of behavior; at high crowd volumes, we observed significant group-level changes in activity budget (increased inactivity, increased locomotion, and decreased environment-related behaviors), increase in some anxiety-related behaviors, and decreased enclosure usage. Although contributing similar effects, it could not be determined if crowd numbers, composition, or noise most affected the troop, nor any chronic effects of exposure to large crowds. Nevertheless, our findings suggest that measures to minimize the impacts of large crowds at the exhibit would be beneficial. Furthermore, we highlight potential discrepancies between common methods for measuring visitor numbers: VGATE is less sensitive to detecting visitor effects on behavioral indices than VDENSITY. Future studies should appropriately match the biological time frame of welfare indicators and visitor measures used to ensure the reliability of findings. 相似文献
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Melissa Remis 《American journal of physical anthropology》1995,97(4):413-433
The objectives of this 27 month study were to document the positional behaviors used by lowland gorillas (Gorilla gorilla gorilla) in the Central African Republic and to compare the effects of body size dimorphism on the use of arboreal substrates. During this study, despite their great size, all gorillas used trees regularly. Predictions concerning the relationship of body size to arboreal behavior were generally upheld. Small branch and suspensory activities were rare for silverbacks. Females used smaller and multiple substrates and suspensory postures more frequently than males. Although females foraged in the periphery of trees, males stayed close to the cores and rarely used terminal branches. In addition to body size, this study found that party size, social rank, and tree structure all influence an animal's substrate choice and subsequent positional activities. Lone males typically remained in the cores of trees where substrates are large. Group males may have been forced to use all parts of trees because others were present. Lone males used small crown trees which provided easy access to terminal branch foods. Males and females foraging together used larger trees (containing more feeding sites) than single sex groups. Female positional behavior may have been affected by the presence of males. When apart from males, females used the cores of trees and larger substrates more than when foraging with males. As habitat and social context both influence substrate use, they should be considered essential components of body-sized based interpretations of the behavior of fossil or extant species. © 1995 Wiley-Liss, Inc. 相似文献
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Based on their geographic proximity to the Virunga Volcanoes (≈ 25 km), the Bwindi-Impenetrable Forest gorillas have been referred to the subspecies Gorilla gorilla beringei. Differences in anatomy, habitat, ecology, and behavior, however, suggest Bwindi gorillas are distinct from those in the Virungas. Relative to Virunga gorillas, Bwindi gorillas live at lower elevations, in warmer temperatures, are much more arboreal, have longer day ranges and larger home ranges, and eat much more fruit and pith, and less bamboo and leaves. Morphological differences reflect the differences in ecology, habitat, and behavior. Bwindi gorillas measured have smaller bodies, relatively longer limbs, hands, and feet, shorter trunks, thumbs, big toes, and tooth row lengths, and narrower trunks and orbital breadths than Virunga gorillas. These differences indicate Bwindi gorillas do not belong to G.g. beringei and should not be referred to as “mountain gorillas.” How unique the distinguishing features of Bwindi gorillas are, and whether or not they should be assigned to a new taxon, depends on the expression of these features in eastern lowland gorillas (G.g. graueri). © 1996 Wiley-Liss, Inc. 相似文献
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Ontogenic development is divided into infant, juvenile, adolescent and adult life‐stages. Although the developmental trajectory of an individual is a flexible entity, which differs within species, environment and sex, life‐stage classifications are generally structured, age‐based systems. This invariably leads to rigidity within a dynamic system and consequently hampers our understanding of primate life history strategies. We propose that life‐stage classifications should be quantitative, flexible entities, which use a reliable measurement of development. Here, we provide a methodological example where placement into a life‐stage is based upon behavioral variance between other similar‐aged individuals. Behavioral data were collected from 12 male (3–11 years old) and 9 female (3–8 years old) captive immature western gorillas (Gorilla gorilla gorilla) housed in five family groups, using continuous focal sampling; 900 hr of data were collected over 131 days. Data were applied to four published life‐stage classifications for mountain gorillas (Gorilla beringei beringei), which showed variable ability to determine life‐stage in western gorillas. A new life‐stage classification (Hutchinson & Fletcher) was proposed specifically for western gorillas, whereby multiple co‐varying behavior provided a robust measure of linear development across immaturity. Each life‐stage was found to be a distinct ontogenic phase and the classification discriminated life‐stage with a high level of accuracy. Using the Hutchinson & Fletcher classification we provide evidence for disparity in developmental trajectories between the sexes from the juvenile period onwards. To expand the understanding of primate life histories, we propose that flexible classifications should be used to enable comparison of allometric life history traits within and between species, from birth onwards. Am. J. Primatol. 72:492–501, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
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We observed a colony of lowland gorillas in order to assess the occurrence of Peaceful Post-Conflict Interactions between Aggressors and Bystanders (PPIAB). We compared the dynamics of PPIAB with those of Peaceful Post-Conflict Interactions between Victims and Bystanders (PPIVB), which are directed toward victims. We confirmed the occurrence of PPIAB (mean Triadic Contact Tendency: 41.7%+/-16.2% SEM) at frequencies comparable to PPIVB. Immature gorillas were responsible for most PPIAB. PPIAB occurred when the bystander was unrelated to either the aggressor or the victim, and when it was a relative of the aggressor. However, affinitive contact rates were higher in the former case. Unlike PPIVB, PPIAB significantly reduced the likelihood of further aggressions within the group, suggesting that they work at an immediate level. Our data also suggest that bystanders decide when a peaceful contact may be too risky; in fact, neither PPIAB nor PPIVB occurred after high-intensity aggressions. 相似文献
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Mätz-Rensing K Kunze M Zöller M Roos C Kiderlen AF Ludwig C Kaup FJ 《Journal of medical primatology》2011,40(6):437-440
Background A 12‐year‐old female western lowland gorilla died in a zoological garden in Germany after exhibiting general neurological signs. Methods Balamuthia mandrillaris was identified as causative agent by indirect immunofluorescent staining of brain sections and confirmed by PCR and respective sequencing. Results The animal suffered from a chronic progressive necrotizing amebic meningoencephalitis. Conclusion This is the first case of Balamuthia amebic encephalitis in Germany. 相似文献
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Artificial insemination in the great apes has not achieved its potential as a tool in maintenance of the endangered captive population. Three factors can influence the success rate of artificial insemination: sperm preparation, site of insemination, and timing of insemination. We have tried to optimize methods regarding these three steps. A modified method for insemination is described which has resulted in a 21% success rate (six term pregnancies from 29 inseminations) in the chimpanzee and which has successfully initiated a pregnancy in a gorilla. 相似文献
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Laurent Prtt Jennifer Mickelberg Jodi Carrigan Tara Stoinski Redouan Bshary Sarah F. Brosnan 《American journal of primatology》2021,83(1)
A goal of the comparative approach is to test a variety of species on the same task. Here, we examined whether the factors that helped capuchin monkeys improve their performance in a dichotomous choice task would generalize to three other primate species: orangutans, gorillas, and drill monkeys. In this task, subjects have access to two options, each resulting in an identical food, but one (the ephemeral option) is only available if it is chosen first, whereas the other one (the permanent option) is always available. Therefore, the food‐maximizing solution is to choose the ephemeral option first, followed by the permanent option for an additional reward. On the original version (plate task), the options were discriminated by the color and pattern of the plates holding the food, while on two subsequent versions we used altered cues that we predicted would improve performance: (1) the color of the foods themselves (color task), which we hypothesized was relevant to primates, who choose foods rather than substrates on which foods are found when foraging, and (2) patterned cups covering the foods (cup task), which we hypothesized would help primates avoid the prepotent response associated with visible food. Like capuchins, all three species initially failed to solve the plate task. However, while orangutans improved their performance from the plate to the color task, they did not for the cup task, and only a few gorillas and no drills succeeded in either task. Unfortunately, our ability to interpret these data was obscured by differences in the subjects' level of experience with cognitive testing and practical constraints that precluded the use of completely identical procedures across species. Nonetheless, we consider what these results can tell us, and discuss the value of conducting studies across multiple sites despite unavoidable differences. 相似文献
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In the present study we investigated the gestural communication of gorillas (Gorilla gorilla). The subjects were 13 gorillas (1-6 years old) living in two different groups in captivity. Our goal was to compile the gestural repertoire of subadult gorillas, with a special focus on processes of social cognition, including attention to individual and developmental variability, group variability, and flexibility of use. Thirty-three different gestures (six auditory, 11 tactile, and 16 visual gestures) were recorded. We found idiosyncratic gestures, individual differences, and similar degrees of concordance between and within groups, as well as some group-specific gestures. These results provide evidence that ontogenetic ritualization is the main learning process involved, but some form of social learning may also be responsible for the acquisition of special gestures. The present study establishes that gorillas have a multifaceted gestural repertoire, characterized by a great deal of flexibility with accommodations to various communicative circumstances, including the attentional state of the recipient. The possibility of assigning Seyfarth and Cheney's [1997] model for nonhuman primate vocal development to the development of nonhuman primate gestural communication is discussed. 相似文献
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Pascale Sicotte 《American journal of primatology》1993,30(1):21-36
This 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. 相似文献
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Clifford SL Anthony NM Bawe-Johnson M Abernethy KA Tutin CE White LJ Bermejo M Goldsmith ML McFarland K Jeffery KJ Bruford MW Wickings EJ 《Molecular ecology》2004,13(6):1551-1565
The geographical distribution of genetic variation within western lowland gorillas (Gorilla gorilla gorilla) was examined to clarify the population genetic structure and recent evolutionary history of this group. DNA was amplified from shed hair collected from sites across the range of the three traditionally recognized gorilla subspecies: western lowland (G. g. gorilla), eastern lowland (G. g. graueri) and mountain (G. g. beringei) gorillas. Nucleotide sequence variation was examined in the first hypervariable domain of the mitochondrial control region and was much higher in western lowland gorillas than in either of the other two subspecies. In addition to recapitulating the major evolutionary split between eastern and western lowland gorillas, phylogenetic analysis indicates a phylogeographical division within western lowland gorillas, one haplogroup comprising gorilla populations from eastern Nigeria through to southeast Cameroon and a second comprising all other western lowland gorillas. Within this second haplogroup, haplotypes appear to be partitioned geographically into three subgroups: (i) Equatorial Guinea, (ii) Central African Republic, and (iii) Gabon and adjacent Congo. There is also evidence of limited haplotype admixture in northeastern Gabon and southeast Cameroon. The phylogeographical patterns are broadly consistent with those predicted by current Pleistocene refuge hypotheses for the region and suggest that historical events have played an important role in shaping the population structure of this subspecies. 相似文献
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To visualize long‐term social relationships among 12 gorillas in a captive breeding group at the San Diego Wild Animal Park, San Diego, CA, the multidimensional scaling (MDS) procedure was applied to proximity (within 5 m) values collected in five different periods over 2.5 years. The resulting two‐dimensional representations clearly show that in samples taken during this 2.5‐year period, the silverback male was surrounded by five adult females, while three infant or young juvenile females, gathered in a body, remained between the silverback male and adult females. Some adult females maintained proximity to the silverback male more frequently than other adult females throughout the five periods. Unlike mountain gorillas in the wild, females with dependent offspring did not tend to stay near the silverback male more frequently than other females, and related females did not tend to spend more time near each other than non‐related females. Three older juvenile or young adult males were plotted the furthest from the silverback male, with gradual changes with increasing age. The usefulness of the MDS procedure, which can be used to visualize easily and clearly the social relationships among individuals, is discussed from the viewpoint of the management of breeding groups of captive gorillas. Zoo Biol 20:197–209, 2001. © 2001 Wiley‐Liss, Inc. 相似文献
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Florence Magliocca Sophie Querouil Annie Gautier‐Hion 《American journal of primatology》1999,48(1):1-14
Population studies are an essential part of conservation actions. Under exceptional observation conditions we studied a western lowland gorilla population visiting the Maya salt‐clearing (north of the Parc national d'Odzala, P.N.O., Congo) over an 8 month period; 36 groups and 18 solitary individuals (a total of 420 individuals) have been identified visiting the clearing, which suggests a high gorilla density in the region. Ninety‐six percent of the gorillas entered the clearing in groups. One‐male groups had a mean size of 11.2. Ninety percent of solitary individuals were silver‐back males. Compared with other populations of both lowland gorillas and mountain gorillas, the Maya population had the highest immature rate and the highest number of infants per female. Ecological correlates that could explain the attractiveness of the Maya clearing are discussed. The present status and the renewal rate of the Maya population indicate the need for further studies and confirm the importance of developing eco‐tourism in this region as part of the sustainable park management activities developed by the ECOFAC programme (European Union). The results also provide arguments to support the proposal for extending the P.N.O. to include this region, which is rich in salt‐clearings and attracts many other key‐species of mammal such as forest elephants. Am. J. Primatol. 48:1–14, 1999. © 1999 Wiley‐Liss, Inc. 相似文献