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Rebecca L. Chancellor - One of the best experts on this subject based on the ideXlab platform.
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Determinants of Reproductive Performance Among Female Gray-Cheeked Mangabeys (Lophocebus albigena) in Kibale National Park, Uganda
International Journal of Primatology, 2015Co-Authors: Małgorzata E. Arlet, Colin A. Chapman, Lynne A. Isbell, Freerk Molleman, Raivo Mänd, Rebecca L. Chancellor, Ants Kaasik, James R. CareyAbstract:Identifying the causes of differential reproductive success is key to understanding natural selection and the forces of selection operating on animals. Here we present results from a 9-yr (2004–2012) study of female reproductive performance in relation to mother’s age and rank, presence of immigrant males, rainfall, and fig fruit abundance in four groups of gray-cheeked mangabeys ( Lophocebus albigena ) in Kibale National Park, Uganda. We found that females had a rank- and age-specific reproductive pattern, with high-ranking females maturing earlier, having their first births earlier, and exhibiting significantly slower reproductive aging than low-ranking females. We also found that both immigrant and resident males were associated with higher birth rates. Finally, we found that reproduction was aseasonal and did not correlate with rainfall, but that births correlated positively with the abundance of fruits of Ficus spp. Our results show broad similarities between arboreal, forest-dwelling gray-cheeked mangabeys and their more terrestrial, open habitat-dwelling papionin relatives in the importance of dominance rank in estrous cycle initiation, first reproduction, and reproductive aging.
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Maternal Investment and Infant Survival in Gray-Cheeked Mangabeys (Lophocebus albigena)
International Journal of Primatology, 2014Co-Authors: Małgorzata E. Arlet, Colin A. Chapman, Lynne A. Isbell, Freerk Molleman, Raivo Mänd, Rebecca L. Chancellor, Ants Kaasik, James R. CareyAbstract:Differences among females in infant survival can contribute substantially to variance in fitness. Infant survival is a product of external risk factors and investment by kin, especially the mother, and is thus closely tied with the evolution of behavior and life history. Here we present a 9-yr study (2004–2012) of infant survival and sex ratio relative to age and dominance ranks of mothers and the presence of immigrant males in a free-ranging population of gray-cheeked mangabeys (Lophocebus albigena) in Kibale National Park, Uganda. We consider immigrant males because they are known to increase infant mortality in several other species. We found that infants of older mothers had higher survival than those of younger mothers but that high rank did not confer a significant benefit on infant survival. Female infants had higher survival than male infants. Young, low-ranking females had more male infants than young, high-ranking females, which had slightly more daughters, but this difference declined as females aged because low-ranking females had more daughters as they aged. With limited data, we found a significant relationship between the presence of male immigrants and infant mortality (falls and unexplained disappearances) to 18 mo. Our results suggest that infant survival in gray-cheeked mangabeys is most precarious when mothers must allocate energy to their own growth as well as to their infants, that sons of young mothers are at greatest risk, and that immigrant males can negatively affect infant survival.
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Food
2013Co-Authors: Rebecca L. Chancellor, Lynne A. IsbellAbstract:site residence time and female competitive relationships in wild gray-cheeked mangabeys (Lophocebus albigena
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Correlations between social context and fecal glucocorticoid metabolite concentrations in free-ranging female gray-cheeked mangabeys (Lophocebus albigena) in Kibale National Park, Uganda.
Folia Biologica, 2013Co-Authors: Małgorzata E. Arlet, Lynne A. Isbell, Freerk Molleman, James R. Carey, Rebecca L. Chancellor, Raivo MändAbstract:An elevated concentration of glucocorticoids is an indicator of stress, and chronically high glucocorticoid levels are often associated with poor health and reduced fertility. We explored conditions that might be stressors in the lives of adult female gray-cheeked mangabeys (Lophocebus albigena) by measuring fecal glucocorticoid metabolites (fGCM) concentrations. During a six-month study we collected 109 fecal samples from 28 adult females from five groups in Kibale National Park, Uganda. We examined fecal fGCM levels of individual females relative to their own reproductive status (cycling or not cycling) and that of other females and to the presence of newcomer (immigrant) males. We found elevated fGCM concentrations in females when other females in their groups were at the peak of sexual swelling, and when immigrant males joined the group.
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Do Dispersing Monkeys Follow Kin? Evidence from Gray-cheeked Mangabeys (Lophocebus albigena)
International journal of primatology, 2011Co-Authors: Rebecca L. Chancellor, William Olupot, Jessica Satkoski, Debbie George, Nathanael I. Lichti, David Glenn Smith, Peter M. WaserAbstract:Among social vertebrates, immigrants may incur a substantial fitness cost when they attempt to join a new group. Dispersers could reduce that cost, or increase their probability of mating via coalition formation, by immigrating into groups containing first- or second-degree relatives. We here examine whether dispersing males tend to move into groups containing fathers or brothers in gray-cheeked mangabeys (Lophocebus albigena) in Kibale National Park, Uganda. We sampled blood from 21 subadult and adult male mangabeys in 7 social groups and genotyped them at 17 microsatellite loci. Twelve genotyped males dispersed to groups containing other genotyped adult males during the study; in only 1 case did the group contain a probable male relative. Contrary to the prediction that dispersing males would follow kin, relatively few adult male dyads were likely first- or second-degree relatives; opportunities for kin-biased dispersal by mangabeys appear to be rare. During 4 yr of observation, adult brothers shared a group only once, and for only 6 wk. Mean relatedness among adult males sharing a group was lower than that among males in different groups. Randomization tests indicate that closely related males share groups no more often than expected by chance, although these tests had limited power. We suggest that the demographic conditions that allow kin-biased dispersal to evolve do not occur in mangabeys, may be unusual among primates, and are worth further attention.
W. Scott Mcgraw - One of the best experts on this subject based on the ideXlab platform.
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The International Encyclopedia of Primatology - Mangabeys (Cercocebus and Lophocebus)
The International Encyclopedia of Primatology, 2017Co-Authors: W. Scott McgrawAbstract:Molecular, morphological, and behavioral data indicate that the primates commonly referred to as mangabeys do not comprise a natural group. The Cercocebus mangabeys are seven species of African monkeys also referred to as “drill-mangabeys.” Cercocebus is the sister taxon of Mandrillus (mandrills and drills). The five species of Lophocebus mangabeys, also known as baboon mangabeys, form a clade with Papio, Rungwecebus, and Theropithecus. The Cercocebus–Mandrillus clade is united by a suite of skeletodental features and behavioral adaptations related to the acquisition and processing of hard-object foods collected from the forest floor. Mangabey diphyly highlights the considerable homoplasy among African papionins. Keywords: conservation; physical/biological anthropology; primatology
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Brief communication: Enamel thickness and durophagy in mangabeys revisited
American journal of physical anthropology, 2011Co-Authors: W. Scott Mcgraw, James D Pampush, David J. DaeglingAbstract:The documentation of enamel thickness variation across primates is important because enamel thickness has both taxonomic and functional relevance. The Old World monkeys commonly referred to as mangabeys have figured prominently in investigations of feeding ecology and enamel thickness. In this article, we report enamel thickness values for four mangabey taxa (Cercocebus atys, Cercocebus torquatus, Lophocebus aterrimus, and Lophocebus albigena), offer revised interpretation of the significance of thick enamel in papionin evolution, and place our new data in a broader comparative framework. Our data indicate that all mangabeys have thick enamel and that the values obtained for Cercocebus and Lophocebus equal or exceed those published for most extant non-human primates. In addition, new field data combined with a current reading of the dietary literature indicate that hard foods make up a portion of the diet of every mangabey species sampled to date. Clarification on the relationship between diet and enamel thickness among mangabeys is important not only because of recognition that mangabeys are not a natural group but also because of recent arguments that explain thick enamel as an evolved response to the seasonal consumption of hard foods.
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Functional morphology of the mangabey mandibular corpus: Relationship to dental specializations and feeding behavior
American journal of physical anthropology, 2007Co-Authors: David J. Daegling, W. Scott McgrawAbstract:Recent molecular and morphological surveys suggest that mangabeys do not represent a monophyletic group. Specifically, Cercocebus is the sister taxon of Mandrillus, whereas Lophocebus forms an unresolved trichotomy with Papio and Theropithecus. The Cercocebus-Mandrillus clade is characterized by skeletal and dental adaptations related to acquisition and processing of hard-object foods that resist decomposition for months on the forest floor. Although species of both mangabey genera can be described as frugivorous seed predators with a strong reliance on hard-object foods, a growing body of evidence indicates that Cercocebus (terrestrial) and Lophocebus (arboreal) mangabeys differ in the hardness of the seeds they consume and the manner in which seeds are processed. The taxa are also distinguished on the basis of dental morphology. Given the purported differences in feeding behaviors of the two mangabey genera, we consider whether there are predictable biomechanical consequences of these behaviors that are reflected in mandibular corpus dimensions. In addition, we present metric data summarizing functional aspects of mangabey mandibular corpus morphology. Mangabey genera are generally not distinguished by differences in relative corpus size, either in postcanine or symphyseal regions. Distinct symphyseal scaling patterns characterize the Papio-Lophocebus clade and the Mandrillus-Cercocebus clade, while the postcanine corpus scales similarly between them. The hypothesis that preferential use of the incisors vs. premolars to initially process these foods results in distinct stress environments is weakly supported, given circumstantial evidence that the relative importance of bending vs. torsion may differ between Cercocebus and Lophocebus. Am J Phys Anthropol, 2007. © 2007 Wiley-Liss, Inc.
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Skeletal and dental morphology of African papionins: unmasking a cryptic clade.
Journal of human evolution, 2002Co-Authors: John G. Fleagle, W. Scott McgrawAbstract:Abstract One of the more perplexing problems in primate systematics concerns the phyletic relationships of the large African monkeys— Mandrillus (including drills), Papio , Lophocebus and Cercocebus . For over twenty years, there has been molecular evidence that mangabeys are an unnatural group and that the terrestrial forms— Cercocebus —are the sister taxon of Mandrillus , while the arboreal forms— Lophocebus mdash;are more closely allied with Papio . Nevertheless, most systematists have been reluctant to accept this scheme due to the lack of morphological evidence. In this paper, we undertake a detailed analysis of the scapula, humerus, radius, ulna, pelvis, femur and dentition of papionin primates. We identify a host of features shared by Cercocebus and Mandrillus to the exclusion of Lophocebus and Papio . The polarity of characters is established by examining an outgroup comprised of several species of Macaca. The features shared by Cercocebus and Mandrillus are functionally related to specific feeding and locomotor behaviors that include aggressive manual foraging, the processing of hard-object foods and the climbing of vertical trunks. We hypothesize that the ability to subsist on hard seeds and nuts gleaned from the forest floor is a key adaptation for the Cercocebus–Mandrillus clade.
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Skeletal and dental morphology supports diphyletic origin of baboons and mandrills
Proceedings of the National Academy of Sciences of the United States of America, 1999Co-Authors: John G. Fleagle, W. Scott McgrawAbstract:Numerous biomolecular studies from the past 20 years have indicated that the large African monkeys Papio, Theropithecus, and Mandrillus have a diphyletic relationship with different species groups of mangabeys. According to the results of these studies, mandrills and drills (Mandrillus) are most closely related to the torquatus–galeritus group of mangabeys placed in the genus Cercocebus, whereas baboons (Papio) and geladas (Theropithecus) are most closely related to the albigena–aterrimus mangabeys, now commonly placed in the genus Lophocebus. However, there has been very little morphological evidence linking mandrills on the one hand and baboons and geladas on the other with different groups of mangabeys. In a study of mangabey locomotion and skeletal anatomy, we have identified features of the postcranial skeleton and the dentition that support the molecular phylogeny and clearly link mandrills with Cercocebus and Papio with Lophocebus. Moreover, the features linking Cercocebus and Mandrillus accord with ecological studies of these species indicating that these two genera are a cryptic clade characterized by unique adaptations for gleaning insects, hard nuts, and seeds from the forest floor.
Peter M. Waser - One of the best experts on this subject based on the ideXlab platform.
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Do Dispersing Monkeys Follow Kin? Evidence from Gray-cheeked Mangabeys (Lophocebus albigena)
International journal of primatology, 2011Co-Authors: Rebecca L. Chancellor, William Olupot, Jessica Satkoski, Debbie George, Nathanael I. Lichti, David Glenn Smith, Peter M. WaserAbstract:Among social vertebrates, immigrants may incur a substantial fitness cost when they attempt to join a new group. Dispersers could reduce that cost, or increase their probability of mating via coalition formation, by immigrating into groups containing first- or second-degree relatives. We here examine whether dispersing males tend to move into groups containing fathers or brothers in gray-cheeked mangabeys (Lophocebus albigena) in Kibale National Park, Uganda. We sampled blood from 21 subadult and adult male mangabeys in 7 social groups and genotyped them at 17 microsatellite loci. Twelve genotyped males dispersed to groups containing other genotyped adult males during the study; in only 1 case did the group contain a probable male relative. Contrary to the prediction that dispersing males would follow kin, relatively few adult male dyads were likely first- or second-degree relatives; opportunities for kin-biased dispersal by mangabeys appear to be rare. During 4 yr of observation, adult brothers shared a group only once, and for only 6 wk. Mean relatedness among adult males sharing a group was lower than that among males in different groups. Randomization tests indicate that closely related males share groups no more often than expected by chance, although these tests had limited power. We suggest that the demographic conditions that allow kin-biased dispersal to evolve do not occur in mangabeys, may be unusual among primates, and are worth further attention.
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Do Dispersing Monkeys Follow Kin? Evidence from Gray-cheeked Mangabeys (Lophocebus albigena)
2010Co-Authors: Rebecca L. Chancellor, William Olupot, Peter M. Waser, Jessica Satkoski, Debbie George, Nathanael I. Lichti, David Glenn Smith, W. OlupotAbstract:# The Author(s) 2011. This article is published with open access at Springerlink.com Abstract Among social vertebrates, immigrants may incur a substantial fitness cost when they attempt to join a new group. Dispersers could reduce that cost, or increase their probability of mating via coalition formation, by immigrating into groups containing first- or second-degree relatives. We here examine whether dispersing males tend to move into groups containing fathers or brothers in gray-cheeked mangabeys (Lophocebus albigena) in Kibale National Park, Uganda. We sampled blood from 21 subadult and adult male mangabeys in 7 social groups and genotyped them at 17 microsatellite loci. Twelve genotyped males dispersed to groups containing other genotyped adult males during the study; in only 1 case did the group contain a probable male relative. Contrary to the prediction that dispersing males would follow kin, relatively few adult male dyads were likely first- or second-degree relatives; opportunities for kin-biased dispersal by mangabeys appear to be rare. During 4 yr of observation, adult brothers shared a group only once, and fo
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Long-term Site Fidelity and Individual Home Range Shifts in Lophocebus albigena
International Journal of Primatology, 2009Co-Authors: Karline R. L. Janmaat, Rebecca L. Chancellor, William Olupot, Malgorzata E. Arlet, Peter M. WaserAbstract:We investigated long-term site fidelity of gray-cheeked mangabey ( Lophocebus albigena ) groups in Kibale National Park, Uganda. Concurrently, we monitored shifts in home range by individual females and subadult and adult males. We documented home range stability by calculating the area of overlap in successive years, and by recording the drift of each group’s monthly centroid from its initial location. Home ranges remained stable for 3 of our 4 groups (overlap over 10 yr >60%). Core areas were more labile, but group centroids drifted an average of only 530 m over the entire decade. Deviations from site fidelity were associated with dispersal or group fission. During natal dispersal, subadult males expanded their home ranges over many months, settling ≤4 home ranges away. Adult males, in contrast, typically dispersed within a few days to an adjacent group in an area of home range overlap. Adult males made solitary forays, but nearly always into areas used by their current group or by a group to which they had previously belonged. After secondary dispersal, they expanded their ranging in the company of their new group, apparently without prior solitary exploration of the new area. Some females also participated in home range shifts. Females shifted home ranges only within social groups, in association with temporary or permanent group splits. Our observations raise the possibility that male mangabeys use a finder-joiner mechanism when moving into new home ranges during secondary dispersal. Similarly, females might learn new resource locations from male immigrants before or during group fission.
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Long-term Site Fidelity and Individual Home Range Shifts in Lophocebus albigena
2009Co-Authors: Karline R. L. Janmaat, Rebecca L. Chancellor, William Olupot, Malgorzata E. Arlet, Peter M. Waser, K. R. L. JanmaatAbstract:# The Author(s) 2009. This article is published with open access at Springerlink.com Abstract We investigated long-term site fidelity of gray-cheeked mangabey (Lophocebus albigena) groups in Kibale National Park, Uganda. Concurrently, we monitored shifts in home range by individual females and subadult and adult males. We documented home range stability by calculating the area of overlap in successive years, and by recording the drift of each group’s monthly centroid from its initial location. Home ranges remained stable for 3 of our 4 groups (overlap over 10 yr>60%). Core areas were more labile, but group centroids drifted an average of only 530 m over the entire decade. Deviations from site fidelity were associated with dispersal or group fission. During natal dispersal, subadult males expanded their home ranges over many months, settling ≤4 home ranges away. Adult males, in contrast, typically dispersed within a few days to an adjacent group in an area of home range overlap. Adult males made solitary forays, but nearly always into areas used by their current group or by a group to which they had previously belonged. After secondary dispersal, they expanded their ranging in the company of their ne
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Patterns of male residency and intergroup transfer in gray-cheeked mangabeys (Lophocebus albigena).
American journal of primatology, 2005Co-Authors: William Olupot, Peter M. WaserAbstract:We describe the movements and fates of 36 collared gray-cheeked male mangabeys (Lophocebus albigena) that resided in seven social groups in Kibale National Park, Uganda. The male mangabeys were captured, radiotagged, and then contacted regularly over a period of up to 8 years. Individuals varied considerably in how tightly they were associated with their groups. “Central” males were usually found in close spatial association with their own groups, but they sometimes visited others. “Peripheral” males were often found several hundred meters away from their own groups. Most adult males were characterized by repeated intergroup transfers, manifested as “visits” and “dispersals.” Visits were transfers that did not result in mating. The visits were brief, and ranged from a few minutes to a few days before the male returned to his previous group, moved on to another group, or returned to solitary life. The term “dispersal” refers to a transfer that results in mating, after which the male remains in the new group. Young males began to drift away from their natal groups in early subadulthood, but the timing of first associations with estrous females in other groups was highly variable. Natal dispersers were generally solitary for a month or more, and at least half moved into nonadjacent groups. Secondary dispersal was common. After they immigrated, adult males remained in a group for a median of 19 months before they emigrated again, with the probability of departure being approximately constant in time. Secondary dispersal was usually made into an adjacent group and lasted less than 7 days. Emigration and immigration were not seasonal, and males emigrated singly and apparently independently; however, immigrations were clumped in time, and male dispersal contributed to considerable heterogeneity of group composition. L. albigena dispersal patterns are intermediate between those described for Papio baboons and forest Cercopithecus, and models that predict demographic consequences of dispersal for baboons can be refined to apply to mangabeys. Am. J. Primatol. 66:331–349, 2005. © 2005 Wiley-Liss, Inc.
Karline R. L. Janmaat - One of the best experts on this subject based on the ideXlab platform.
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Exploring New Areas: How Important is Long-Term Spatial Memory for Mangabey ( Lophocebus albigena johnstonii ) Foraging Efficiency?
International Journal of Primatology, 2010Co-Authors: Karline R. L. Janmaat, Rebecca L. ChancellorAbstract:Studies of primate foraging efficiency during the exploration of new areas can provide important insights into the adaptive value of long-term spatial memory. After 6 yr of observation of a group of gray-cheeked mangabeys (Lophocebus albigena johnstonii) in Kibale National Park, Uganda, we observed exploration of a new area, followed 7 mo later by a group split. We recorded their ranging and foraging behavior for 22 mo after the first exploration. Controlling for weather variables, we found that mangabeys moved longer daily travel distances, explored more area per day, and had larger group spreads in the new area compared to the old area in both parent and daughter groups. The increase in search swath in the new area likely enabled the monkeys to counteract their lack of knowledge of food locations in the new area, as the efficiency in finding fruit in general did not differ between the old and new areas. We did, however, find a lower efficiency in finding fruit from preferred fig trees whose edibility could not be assessed by visual cues in the new area. Fig finding efficiency remained lower, even when we controlled for potential differences in fig density. In addition, mangabeys traveled and foraged less often on the ground in the new compared to the old area. However, when the monkeys became more familiar with the new area, terrestrial behavior increased. Our results are consistent with the hypothesis that when monkeys move into an area in which they have no experience, an absence of knowledge acquired via long-term spatial memory decreases their foraging efficiency.
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Long-term Site Fidelity and Individual Home Range Shifts in Lophocebus albigena
International Journal of Primatology, 2009Co-Authors: Karline R. L. Janmaat, Rebecca L. Chancellor, William Olupot, Malgorzata E. Arlet, Peter M. WaserAbstract:We investigated long-term site fidelity of gray-cheeked mangabey ( Lophocebus albigena ) groups in Kibale National Park, Uganda. Concurrently, we monitored shifts in home range by individual females and subadult and adult males. We documented home range stability by calculating the area of overlap in successive years, and by recording the drift of each group’s monthly centroid from its initial location. Home ranges remained stable for 3 of our 4 groups (overlap over 10 yr >60%). Core areas were more labile, but group centroids drifted an average of only 530 m over the entire decade. Deviations from site fidelity were associated with dispersal or group fission. During natal dispersal, subadult males expanded their home ranges over many months, settling ≤4 home ranges away. Adult males, in contrast, typically dispersed within a few days to an adjacent group in an area of home range overlap. Adult males made solitary forays, but nearly always into areas used by their current group or by a group to which they had previously belonged. After secondary dispersal, they expanded their ranging in the company of their new group, apparently without prior solitary exploration of the new area. Some females also participated in home range shifts. Females shifted home ranges only within social groups, in association with temporary or permanent group splits. Our observations raise the possibility that male mangabeys use a finder-joiner mechanism when moving into new home ranges during secondary dispersal. Similarly, females might learn new resource locations from male immigrants before or during group fission.
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Long-term Site Fidelity and Individual Home Range Shifts in Lophocebus albigena
2009Co-Authors: Karline R. L. Janmaat, Rebecca L. Chancellor, William Olupot, Malgorzata E. Arlet, Peter M. Waser, K. R. L. JanmaatAbstract:# The Author(s) 2009. This article is published with open access at Springerlink.com Abstract We investigated long-term site fidelity of gray-cheeked mangabey (Lophocebus albigena) groups in Kibale National Park, Uganda. Concurrently, we monitored shifts in home range by individual females and subadult and adult males. We documented home range stability by calculating the area of overlap in successive years, and by recording the drift of each group’s monthly centroid from its initial location. Home ranges remained stable for 3 of our 4 groups (overlap over 10 yr>60%). Core areas were more labile, but group centroids drifted an average of only 530 m over the entire decade. Deviations from site fidelity were associated with dispersal or group fission. During natal dispersal, subadult males expanded their home ranges over many months, settling ≤4 home ranges away. Adult males, in contrast, typically dispersed within a few days to an adjacent group in an area of home range overlap. Adult males made solitary forays, but nearly always into areas used by their current group or by a group to which they had previously belonged. After secondary dispersal, they expanded their ranging in the company of their ne
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Evidence for a spatial memory of fruiting states of rainforest trees in wild mangabeys
Animal Behaviour, 2006Co-Authors: Karline R. L. Janmaat, Richard W. Byrne, Klaus ZuberbühlerAbstract:We investigated the ranging behaviour of two groups of wild mangabey monkeys (sooty mangabeys, Cercocebus atys atys, and grey-cheeked mangabeys, Lophocebus albigena johnstoni) relative to a number of preselected target trees within their home range. We observed the groups' visiting patterns and speed when they approached within a critical distance of a target tree as a function of the tree's fruiting state. For both groups, the likelihood of coming into sight or actually entering these trees was significantly higher if fruit was available. Target trees with fruit were also approached significantly faster than were trees without fruits. These behavioural differences were unlikely to be the result of auditory, visual or olfactory cues available over long distances, suggesting that monkeys relied on spatial memory to relocate fruit trees and distinguish between trees that had and had not carried fruit in the immediate past. Results further indicated that the monkeys clearly distinguished between different types of fruit-bearing target trees. We suggest that the monkeys used memory of previous feeding experience to assess each tree's differences and were able to anticipate changes in fruit quality. We found no evidence that individuals belonging to a particular age or sex class led the group towards trees with fruit more often than did others.
William Olupot - One of the best experts on this subject based on the ideXlab platform.
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Do Dispersing Monkeys Follow Kin? Evidence from Gray-cheeked Mangabeys (Lophocebus albigena)
International journal of primatology, 2011Co-Authors: Rebecca L. Chancellor, William Olupot, Jessica Satkoski, Debbie George, Nathanael I. Lichti, David Glenn Smith, Peter M. WaserAbstract:Among social vertebrates, immigrants may incur a substantial fitness cost when they attempt to join a new group. Dispersers could reduce that cost, or increase their probability of mating via coalition formation, by immigrating into groups containing first- or second-degree relatives. We here examine whether dispersing males tend to move into groups containing fathers or brothers in gray-cheeked mangabeys (Lophocebus albigena) in Kibale National Park, Uganda. We sampled blood from 21 subadult and adult male mangabeys in 7 social groups and genotyped them at 17 microsatellite loci. Twelve genotyped males dispersed to groups containing other genotyped adult males during the study; in only 1 case did the group contain a probable male relative. Contrary to the prediction that dispersing males would follow kin, relatively few adult male dyads were likely first- or second-degree relatives; opportunities for kin-biased dispersal by mangabeys appear to be rare. During 4 yr of observation, adult brothers shared a group only once, and for only 6 wk. Mean relatedness among adult males sharing a group was lower than that among males in different groups. Randomization tests indicate that closely related males share groups no more often than expected by chance, although these tests had limited power. We suggest that the demographic conditions that allow kin-biased dispersal to evolve do not occur in mangabeys, may be unusual among primates, and are worth further attention.
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Do Dispersing Monkeys Follow Kin? Evidence from Gray-cheeked Mangabeys (Lophocebus albigena)
2010Co-Authors: Rebecca L. Chancellor, William Olupot, Peter M. Waser, Jessica Satkoski, Debbie George, Nathanael I. Lichti, David Glenn Smith, W. OlupotAbstract:# The Author(s) 2011. This article is published with open access at Springerlink.com Abstract Among social vertebrates, immigrants may incur a substantial fitness cost when they attempt to join a new group. Dispersers could reduce that cost, or increase their probability of mating via coalition formation, by immigrating into groups containing first- or second-degree relatives. We here examine whether dispersing males tend to move into groups containing fathers or brothers in gray-cheeked mangabeys (Lophocebus albigena) in Kibale National Park, Uganda. We sampled blood from 21 subadult and adult male mangabeys in 7 social groups and genotyped them at 17 microsatellite loci. Twelve genotyped males dispersed to groups containing other genotyped adult males during the study; in only 1 case did the group contain a probable male relative. Contrary to the prediction that dispersing males would follow kin, relatively few adult male dyads were likely first- or second-degree relatives; opportunities for kin-biased dispersal by mangabeys appear to be rare. During 4 yr of observation, adult brothers shared a group only once, and fo
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Long-term Site Fidelity and Individual Home Range Shifts in Lophocebus albigena
International Journal of Primatology, 2009Co-Authors: Karline R. L. Janmaat, Rebecca L. Chancellor, William Olupot, Malgorzata E. Arlet, Peter M. WaserAbstract:We investigated long-term site fidelity of gray-cheeked mangabey ( Lophocebus albigena ) groups in Kibale National Park, Uganda. Concurrently, we monitored shifts in home range by individual females and subadult and adult males. We documented home range stability by calculating the area of overlap in successive years, and by recording the drift of each group’s monthly centroid from its initial location. Home ranges remained stable for 3 of our 4 groups (overlap over 10 yr >60%). Core areas were more labile, but group centroids drifted an average of only 530 m over the entire decade. Deviations from site fidelity were associated with dispersal or group fission. During natal dispersal, subadult males expanded their home ranges over many months, settling ≤4 home ranges away. Adult males, in contrast, typically dispersed within a few days to an adjacent group in an area of home range overlap. Adult males made solitary forays, but nearly always into areas used by their current group or by a group to which they had previously belonged. After secondary dispersal, they expanded their ranging in the company of their new group, apparently without prior solitary exploration of the new area. Some females also participated in home range shifts. Females shifted home ranges only within social groups, in association with temporary or permanent group splits. Our observations raise the possibility that male mangabeys use a finder-joiner mechanism when moving into new home ranges during secondary dispersal. Similarly, females might learn new resource locations from male immigrants before or during group fission.
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Long-term Site Fidelity and Individual Home Range Shifts in Lophocebus albigena
2009Co-Authors: Karline R. L. Janmaat, Rebecca L. Chancellor, William Olupot, Malgorzata E. Arlet, Peter M. Waser, K. R. L. JanmaatAbstract:# The Author(s) 2009. This article is published with open access at Springerlink.com Abstract We investigated long-term site fidelity of gray-cheeked mangabey (Lophocebus albigena) groups in Kibale National Park, Uganda. Concurrently, we monitored shifts in home range by individual females and subadult and adult males. We documented home range stability by calculating the area of overlap in successive years, and by recording the drift of each group’s monthly centroid from its initial location. Home ranges remained stable for 3 of our 4 groups (overlap over 10 yr>60%). Core areas were more labile, but group centroids drifted an average of only 530 m over the entire decade. Deviations from site fidelity were associated with dispersal or group fission. During natal dispersal, subadult males expanded their home ranges over many months, settling ≤4 home ranges away. Adult males, in contrast, typically dispersed within a few days to an adjacent group in an area of home range overlap. Adult males made solitary forays, but nearly always into areas used by their current group or by a group to which they had previously belonged. After secondary dispersal, they expanded their ranging in the company of their ne
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Patterns of male residency and intergroup transfer in gray-cheeked mangabeys (Lophocebus albigena).
American journal of primatology, 2005Co-Authors: William Olupot, Peter M. WaserAbstract:We describe the movements and fates of 36 collared gray-cheeked male mangabeys (Lophocebus albigena) that resided in seven social groups in Kibale National Park, Uganda. The male mangabeys were captured, radiotagged, and then contacted regularly over a period of up to 8 years. Individuals varied considerably in how tightly they were associated with their groups. “Central” males were usually found in close spatial association with their own groups, but they sometimes visited others. “Peripheral” males were often found several hundred meters away from their own groups. Most adult males were characterized by repeated intergroup transfers, manifested as “visits” and “dispersals.” Visits were transfers that did not result in mating. The visits were brief, and ranged from a few minutes to a few days before the male returned to his previous group, moved on to another group, or returned to solitary life. The term “dispersal” refers to a transfer that results in mating, after which the male remains in the new group. Young males began to drift away from their natal groups in early subadulthood, but the timing of first associations with estrous females in other groups was highly variable. Natal dispersers were generally solitary for a month or more, and at least half moved into nonadjacent groups. Secondary dispersal was common. After they immigrated, adult males remained in a group for a median of 19 months before they emigrated again, with the probability of departure being approximately constant in time. Secondary dispersal was usually made into an adjacent group and lasted less than 7 days. Emigration and immigration were not seasonal, and males emigrated singly and apparently independently; however, immigrations were clumped in time, and male dispersal contributed to considerable heterogeneity of group composition. L. albigena dispersal patterns are intermediate between those described for Papio baboons and forest Cercopithecus, and models that predict demographic consequences of dispersal for baboons can be refined to apply to mangabeys. Am. J. Primatol. 66:331–349, 2005. © 2005 Wiley-Liss, Inc.
