[cytogenetic study of six species or sub-species of mangabeys monkeys (papiinae, cercopithecidae) (author's transl)].chromosome banding patterns of six mangabey species or sub-species are studied and compared. by comparison with the other papiinae previously studied (papio and macaca) lophocebus albigena and l. aterrimus possess very similar karyotypes, differing a most by a pericentric inversion of the y chromosome. the other four, cercocebus torquatus torquatus, c. t. fuliginosus, c. galeritus galeritus and c. g. chrysogaster differ by a complex rearrangement of chromosome no. 10 and by acquisition of hetero ...1979115374
frequency and intensity discrimination in mongolian gerbils, african monkeys and humans.frequency (delta f) and intensity (delta i) difference limens were directly compared in mongolian gerbils (meriones unguiculatus), old world african monkeys (cercopithecus mitis, cercocebus albigena), and humans. methods employed a repeating background ax discrimination procedure, and positive (food) reinforcement for animals. for delta i, there were small quantitative differences between the species. at 1 khz, 70 db spl, dls averaged 2.82 db for gerbils, 2.29 db for monkeys, and 0.75 db for hum ...19921618711
temporal integration in two species of old world monkeys: blue monkeys (cercopithecus mitis) and grey-cheeked mangabeys (cercocebus albigena).changes in auditory sensitivity as a function of signal duration were studied in two species of old world monkeys. testing was conducted under free-field conditions with pure tones 250, 800, 1600, and 4000 hz in frequency. test stimuli ranged in duration from 35-2000 ms. the results showed that the temporal integration functions for the blue monkeys were similar to those reported for rhesus monkeys [t. d. clack, j. acoust. soc. am. 40, 1140-1146 (1966)], but differed significantly from those for ...19863700861
positional behavior in five sympatric old world monkeys.observations of positional behavior and habitat use were recorded on focal individuals of five species of old world monkeys at kibale forest, uganda, through the dry season of 1990 and 1991. cercopithecus ascanius, cercopithecus mitis, cercocebus albigena, colobus badius, and colobus guereza commonly utilize five similar types of positional behavior (i.e., quadrupedalism, leaping, climbing, sitting, and standing), but in varying frequencies and situations. as a group, colobines use oblique suppo ...19957645673
further description of blood stages of plasmodium petersi from cercocebus albigena monkey.additional information is given on the erythrocytic stages of plasmodium petersi (poirriez, baccam, dei-cas, brogan et landau, 1933), which was found in a cercocebus albigena monkey from the central-african republic. the first colour pictures of p. petersi are presented. in 60% of young trophozoites, the vacuole is divided into two or three parts by thin cytoplasmic streaks. in young trophozoites and almost mature schizonts, 80% of nuclei are oval or kidney-shaped; they are two-coloured; measure ...19947883248
the primate community of the lopé reserve, gabon: diets, responses to fruit scarcity, and effects on biomass.the diets of all diurnal primates (gorilla g. gorilla, pan t. troglodytes, mandrillus sphinx, colobus satanas, cercocebus albigena, cercopithecus nictitans, c. pogonias, c. cephus) in the lópe reserve, central gabon, are described from qualitative and quantitative data collected over 10 years. a total of 397 foods were recorded, of which 91% were from plants. the diet of seven of the eight species were numerically dominated by fruit, the exception being colobus satanas with a diet dominated by s ...19979108968
some gastro-intestinal parasites of zoonotic (public health) importance commonly observed in old world non-human primates in kenya.a study was undertaken to categorise some gastro-intestinal (git) parasites commonly observed in kenyan non-human primates (nhps) on the basis of their health implications for humans. six species of locally available non-human primates, namely olive baboons (papio cyanocephalus anubis), vervet monkey (cercopithecus aethiops), sykes monkey (cercopithecus mitis), black and white colobus (colobus abyssinicus), debrazzas monkey (cercopithecus neglectus) and grey and black mangabeys (cercocebus torqu ...19989776144
bone geometry in cercopithecoid mandibles.this study explores the relation between cortical bone geometry in the mandibular corpus and in vivo masticatory stress patterns and dietary specialization in cercopithecoid primates. cortical bone distribution in the mandibles of three species of old world monkeys (macaca fascicularis, procolobus badius, lophocebus albigena) was measured by computed tomography. the arrangement of bone within sections was quantified as (1) the ratio of cortical area to the enclosed (total) subperiosteal area; (2 ...200211922874
distribution, population density, and status of sympatric cercopithecids in the campo-ma'an area, southwestern cameroon.a study on species composition, distribution, and population density of cercopithecids in the campo-ma'an area, southwestern cameroon, was undertaken from december 1997 until august 2000. a total of 665.5 km of line transects was used for the census. thirteen diurnal primate species including five endangered species (gorilla g. gorilla, pan troglodytes, mandrillus sphinx, colobus satanas, cercocebus torquatus) were recorded in the campo forest, the greatest part of which is a logging concession. ...200212145397
hardness of cercopithecine foods: implications for the critical function of enamel thickness in exploiting fallback foods.we evaluate the hardness of foods consumed by sympatric cercopithecus ascanius (redtail guenons) and lophocebus albigena (grey-cheeked mangabeys), and consider how selection might operate to influence foraging adaptations. since l. albigena has among the thickest dental enamel in extant primates and is commonly referred to as a hard-object consumer, we predicted that their diet would be harder than that of the guenon. data on diet and food hardness (as measured by resistance to puncture and crus ...200415386250
dental microwear and diets of african early homo.conventional wisdom ties the origin and early evolution of the genus homo to environmental changes that occurred near the end of the pliocene. the basic idea is that changing habitats led to new diets emphasizing savanna resources, such as herd mammals or underground storage organs. fossil teeth provide the most direct evidence available for evaluating this theory. in this paper, we present a comprehensive study of dental microwear in plio-pleistocene homo from africa. we examined all available ...200616226788
spatial distribution of primates in a mosaic of colonizing and old growth forest at ngogo, kibale national park, uganda.primate censuses were conducted in a mosaic of colonizing (two locations) and old-growth forests using line transect methods at the ngogo study site, kibale national park, uganda. black and white colobus monkeys (colobus guereza) were encountered more frequently in the colonizing forests than in the old growth forest, while chimpanzees (pan troglodytes) were encountered more frequently in the old growth forest than in colonizing forests. although not significant, results suggest that blue monkey ...200616479411
molar microwear in praeanthropus afarensis: evidence for dietary stasis through time and under diverse paleoecological conditions.molar microwear fabrics in extant mammals vary with diet and, more particularly, the physical properties of the items that are consumed. praeanthropus afarensis is well represented in the fossil record over a prolonged and radiometrically controlled temporal span, and reasonably robust paleoecological reconstructions are available for the various localities from which it is known. we therefore examined molar microwear in this species to determine whether diet varied in relation to time or in res ...200616750841
primate abundance along five transect lines at ngogo, kibale national park, uganda.using the line transect methods, i studied the primate density at ngogo, kibale national park, uganda for 18 months. comparisons with other studies show that the population of red colobus monkeys (procolobus rufomitratus) and blue monkeys (cercopithecus mitis) is declining, whereas the populations of black-and-white colobus (colobus guereza), red-tailed monkeys (cercopithecus ascanius), grey-cheeked mangabeys (lophocebus albigena), baboons (papio anubis), and chimpanzees (pan troglodytes) remain ...200717330309
identification and molecular characterization of new stlv-1 and stlv-3 strains in wild-caught nonhuman primates in cameroon.humans and simian species are infected by deltaretroviruses (htlv and stlv respectively), which are collectively called primate t-cell lymphotropic viruses (ptlvs). in humans, four types of htlv have been described (htlv-1 to -4) with three of them having closely related simian virus analogues named stlv-1, 2 and 3. in this study, our aim was to search for a simian htlv-4-related virus and to document and characterize further the diversity of stlv infections in wild primate populations. we scree ...200817976676
extensive survey on the prevalence and genetic diversity of sivs in primate bushmeat provides insights into risks for potential new cross-species evaluate the risk of cross-species transmissions of sivs from non-human primates to humans at the primate/hunter interface, a total of 2586 samples, derived from primate bushmeat representing 11 different primate species, were collected at 6 distinct remote forest sites in southeastern cameroon and in yaoundé, the capital city. siv prevalences were estimated with an updated siv lineage specific gp41 peptide elisa covering the major part of the siv diversity. siv positive samples were confirme ...201019393772
the phylogenetic roots of cognitive dissonance.we presented 7 old world monkeys (japanese macaques [macaca fuscata], gray-cheeked mangabey [lophocebus albigena], rhesus macaques [macaca mulatta], bonnet macaque [macaca radiate], and olive baboon [papio anubis]), 3 chimpanzees (pan troglodytes), 6 members of the parrot (psittacinae) family, and 4 american black bears (ursus americanus) with a cognitive dissonance paradigm modeled after egan, santos, and bloom (2007). in experimental trials, subjects were given choices between 2 equally prefer ...201020836593
brief communication: enamel thickness and durophagy in mangabeys revisited.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 ...201122101774
postreproductive survival and behavior in a free-ranging female mangabey.the survival and behavior of a postreproductive free-ranging female cercocebus albigena is documented; her patterns of grooming, aggression, and other social and spatial relationships with members of her group are described and compared with those of other, cycling, females. the phenomenon of female postreproductive survival in free-ranging nonhuman primates is briefly reviewed.200095995
enamel microwear texture properties of igf 11778 (oreopithecus bambolii) from the late miocene of baccinello, italy.late miocene oreopithecus bambolii has been posited as a folivore from its pronounced molar shearing crests. however, scanning electron microscopy yields conflicting results with one study of oreopithecus showing folivory and another indicating a coarser diet was consumed. to address this debate, the dietary proclivities of the well-known igf 11778 oreopithecus bambolii specimen are reconstructed by comparing the enamel texture properties of this specimen to extant alouatta palliata (n = 11), ce ...201323833018
teasing apart the contributions of hard dietary items on 3d dental microtextures in primates.3d dental microtexture analysis is a powerful tool for reconstructing the diets of extinct primates. this method is based on the comparison of fossils with extant species of known diet. the diets of primates are highly diversified and include fruits, seeds, grass, tree leaves, bark, roots, tubers, and animal resources. fruits remain the main component in the diets of most primates. we tested whether the proportion of fruit consumed is correlated with dental microtexture. two methods of microtext ...201222705031
public health significance of zoonotic bacterial pathogens from bushmeat sold in urban markets of gabon, central africa.wild animal meat represents an important source of protein for many people in central africa. also known as bushmeat, this meat commodity is derived from wild animals hunted under uncontrolled conditions, transported to distant markets under rudimentary or no hygienic methods, and often eviscerated >24 hr after death. considering the plausible role of wildlife as a reservoir for bacterial zoonotic pathogens, bushmeat may be an important public health risk in central africa. this cross-sectional ...201222740547
variability in social visual attention in the red-capped mangabey (cercocebus torquatus torquatus) and the grey-cheeked mangabey (cercocebus albigena albigena). 200810567831
reductions in primate abundance and diversity in a multiuse protected area: synergistic impacts of hunting and logging in a congo basin forest.this article explores spatial and temporal changes in diurnal primate abundance and behavior in response to hunting, logging, and conservation at the dzanga sangha dense forest reserve (rds), central african republic over time. we use a combination of line-transect surveys in 2002 and 2009 (n = 540 km) and ethnographic interviews (n = 210) to investigate changes in the status of cercopithecines and colobines at rds, with additional comparisons to earlier work. this protected area was lightly log ...201222644576
do dispersing monkeys follow kin? evidence from gray-cheeked mangabeys (lophocebus albigena).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 an ...201121475401
folivory or fruit/seed predation for mesopithecus, an earliest colobine from the late miocene of eurasia?here we compare dental microwear textures from specimens of the fossil genus mesopithecus (cercopithecidae, colobinae) from the late miocene of eastern europe with dental microwear textures from four extant primate species with known dietary differences. results indicate that the dental microwear textures of mesopithecus differ from those of extant leaf eaters alouatta palliata and trachypithecus cristatus and instead resemble more closely those of the occasional hard-object feeders cebus apella ...200919733899
food site residence time and female competitive relationships in wild gray-cheeked mangabeys (lophocebus albigena).authors of socioecological models propose that food distribution affects female social relationships in that clumped food resources, such as fruit, result in strong dominance hierarchies and favor coalition formation with female relatives. a number of old world monkey species have been used to test predictions of the socioecological models. however, arboreal forest-living old world monkeys have been understudied in this regard, and it is legitimate to ask whether predominantly arboreal primates ...200919633733
social factors increase fecal testosterone levels in wild male gray-cheeked mangabeys (lophocebus albigena).testosterone can be expected to play a significant role in mediating behavior and life history in social animals, but the number of species with data from the wild is still too small to make generalizations. we investigated the influence of social factors (social status, aggression, and reproductive females) and environmental variation (rainfall and temperature) on fecal testosterone concentrations in wild male gray-cheeked mangabeys (lophocebus albigena) living in five groups in kibale national ...201121376722
postural effect on manual laterality in different tasks in captive grey-cheeked mangabey (lophocebus albigena).the authors examined the effects of task complexity and posture on laterality and compared lateralization during different tasks in 9 captive grey-cheeked mangabeys (lophocebus albigena) during spontaneous food processing and 3 experimental tasks. comparisons with data of red-capped mangabeys (cercocebus torquatus torquatus; semiterrestrial species) were used. less than half the monkeys were lateralized for simple everyday activities, but 6 were lateralized for complex daily activities. moreover ...200717516799
primates take weather into account when searching for fruits.temperature and solar radiation are known to influence maturation of fruits and insect larvae inside them . we investigated whether gray-cheeked mangabeys (lophocebus albigena johnstonii) of kibale forest, uganda, take these weather variables into account when searching for ripe figs or unripe figs containing insect larvae. we predicted that monkeys would be more likely to revisit a tree with fruit after several days of warm and sunny weather compared to a cooler and more cloudy period. we prese ...200616782015
patterns of male residency and intergroup transfer in gray-cheeked mangabeys (lophocebus albigena).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" ...200516104031
red colobus as prey: the leaping habits of five sympatric old world monkeys.this study explored the leaping habits of five sympatric old world monkeys (colobus badius, colobus guereza, cercopithecus ascanius, cercopithecus mitis and cercocebus albigena) in an attempt to determine why chimpanzees prefer to hunt red colobus. we videotaped the leaps of the monkeys for 3 months in uganda's kibale national park. data were collected on leap preparation time as well as several other variables of the leaps. the leap preparation time of red colobus was found to be about double t ...200515775681
mangabey (cercocebus albigena) ranging patterns in relation to fruit availability and the risk of parasite infection in kibale national park, uganda.two opposing hypotheses concerning determinants of mangabey (cercocebus albigena) ranging patterns have been advocated. one hypothesis suggests that ranging patterns of mangabeys are largely a response to fruit availability, while the other hypothesis advocates that concerns of fruit availability are supplemented or overridden by concerns of fecal contamination and that the risk of parasite infection, especially during dry weather, determines their pattern of range use. in this 9 month study of ...19979294642
competition, predation, and the evolutionary significance of the cercopithecine cheek pouch: the case of cercopithecus and lophocebus.reports of cercopithecine cheek pouch use and functional significance are largely anecdotal, and to date there have been no investigations into its use by species living in closed forest habitats. here, i report on cheek pouch use in cercopithecus ascanius and lophocebus albigena in the kibale national park, uganda, between july-october 1997. two hypotheses were evaluated: this feature was selected for because of its role in 1) increasing feeding efficiency via a reduction in potential feeding c ...200515386232
influence of food dispersion on feeding activity and social interactions in captive lophocebus albigena and cercocebus torquatus torquatus.we analysed the impact of the distribution of food items on feeding activity and social interactions in captive red-capped and grey-cheeked mangabeys. three different feeding situations were presented: food items were either placed in a single heap or dispersed in several smaller heaps on the ground or in space. social interactions were estimated by the frequency of positive, as well as of negative social interactions and by the structure of visual social attention. feeding activity was estimate ...200515349792
polyspecific associations of cercocebus albigena: geographic variation and ecological correlates.the characteristics of mixed-species groups and interspecific interactions involving the mangabey, cercocebus albigena, are described. polyspecific associations are common and behaviorally complex. in uganda, ecological data suggest that associations with some species are related to foraging, although evidence that these associations benefit the individuals involved remains equivocal. west african data indicate considerable geographic variability in polyspecific association tendencies.19807191390
visual categorization of natural and abstract items in forest monkeys and humans.a preference for novelty paradigm was used to investigate whether mangabeys (lophocebus albigena), an arboreal non-human primate species, were able to discriminate and to categorize different visual stimuli belonging to natural (food items) and abstract (non-food items) categories. in a comparative perspective human subjects were tested with the same procedure and the same stimuli. two out of four mangabeys and three out of the four humans showed significant preference for novelty when comparing ...200111390091
seasonal variation in the feeding ecology of the grey-cheeked mangabey (lophocebus albigena) in cameroon.seasonal fluctuations in resource abundance often cause primates to change their feeding behavior and ecology. the objective of this study was to examine the response of a largely frugivorous monkey, the grey-cheeked mangabey (lophocebus albigena), to seasonal variations in fruit abundance. we used 15-min scan sampling to quantify feeding, activity, and habitat use by monkeys between february and december 1998 in the dja reserve, cameroon. l. albigena were found to have omnivorous feeding habits ...200111376447
reproductive cycles of the mangabey cercocebus albigena. 19704985669
the susceptibility of cercocebus albigena johnstoni (lydekker) to yellow fever. 195613340675
affiliative behavior of adult female sooty mangabeys (cercocebus atys).a 14-month study of 30 adult female members of a captive group of sooty mangabeys investigated their affiliative interactions with group members of varying age and sex. the adult females preferentially affiliated with other adults and interacted less than expected with immature group members. dyadic frequencies suggested especially frequent affiliation with the three resident adult males, although the pattern of interaction with each male was distinct and apparently was related to age and domina ...198831968897
catarrhine photopigments are optimized for detecting targets against a foliage background.the colour vision of many primates is trichromatic, whereas that of all other mammals is thought to be dichromatic or monochromatic. moreover, the triplets of cone pigments in different catarrhines (old world apes and monkeys) are strikingly similar in their spectral positions. we ask whether the selective advantage of trichromacy lies in an enhanced ability to find edible leaves or fruit. further, we ask whether any factor in these two search tasks has constrained the particular set of cone spe ...200010851115
the blood-stages of plasmodium georgesi, p. gonderi and p. petersi: course of untreated infection in their natural hosts and additional morphological distinctive the blood of a cercocebus albigena and of a c. galeritus agilis monkey, the infection with plasmodium gonderi was found to follow its well-known chronic course; p. georgesi seemed to occur as a relapsing type of malaria parasite; p. petersi was found for only a few days and at a low level in c. albigena (end of an attack?). as shown by using polarized light, the pigment granules appeared mostly as fine dots in p. georgesi, short rods in p. gonderi and long needles in p. petersi. the three spe ...19958559586
[cytogenic study of lophocebus albigena (primate catarrhini cercopithecidae). description of a male karyotype].gtg chromosomic banding of a male and a female lophocebus albigena is reported. the chromosome number of the karyotypes is 2 n = 42, characterized by a pair of marked chromosomes and a mediocentric y chromosome, similar to that of the lophocebus aterimus.19806781770
the perception of vocal signals by blue monkeys and grey-cheeked mangabeys.old world forest primates may need to signal vocally over long distances in noisy habitats. perceptual experiments focused on the audibility of signals in noise were conducted in the laboratory using standard psychoacoustical methods. six human listeners, two blue monkeys (cercopithecus mitis), and two grey-cheeked mangabeys (cercocebus albigena) served as subjects. based upon measurements of east african rain forests (brown and waser 1984) testing was conducted in the presence of simulated rain ...19863732496
scanning electron microscopic analysis of dental wear on the heavily worn second molars of the wild japanese monkey (macaca fuscata).microscopic features on scanning electron micrographs of epoxy-replicas of the second molars of nine wild-caught adult female japanese monkeys, macaca fuscata, from oita takasakiyama, kyushu, were measured using a digitizer. these monkeys had been fed a monkey-diet during three or four days of captivity before replicas were made. six of these specimens showed such heavily worn second molars that narrow peripheral enamel bands surrounded large dentin exposures and the cusps of the others had been ...19911947932
odontometric study of african monkey teeth.univariate analysis of the mesiodistal and buccolingual crown diameters of cercocebus albigena, cercopithecus aethiops and cercopithecus ascanius revealed a complex pattern of contrasts depending upon which tooth dimension was compared. by contrast, multivariate analysis discriminated between the dentitions of cercocebus albigena on the one hand and cercopithecus aethiops and cercopithecus ascanius on the other hand, but whether these differences reflected genetic or environmental factors requir ...1976823785
call rates of mothers change with maternal experience and with infant characteristics in free-ranging gray-cheeked mangabeys.studies have shown that becoming a mother triggers important social changes within females, according to both social experience and infant characteristics, showing different maternal concerns. but how this impacts call usage has been far less studied. based on 6 months of observations of five free-ranging groups of gray-cheeked mangabeys, we investigated variations in the production of three call types (contact, excitement, and alarm calls) in 29 females of different ages, dominance ranks, and i ...201627273714
fragmented living: behavioural ecology of primates in a forest fragment in the lopé reserve, gabon.a 17-month study was made of the primates using a 9-ha "island" of forest, surrounded by savanna, in the northern part of the lopé reserve, gabon. one group ofcercopithecus cephus (plus a young malecercopithecus nictitans who was in permanent association with them) were resident in the fragment and groups of five other species of primates made visits during 127 days of observation:pan troglodytes, 15 visits;cercocebus albigena, 10;colobus satanas, 3;cercopithecus nictitans, 2;c. pogonias, 1. vis ...199923179544
co-infection and cross-species transmission of divergent hepatocystis lineages in a wild african primate community.hemoparasites of the apicomplexan family plasmodiidae include the etiological agents of malaria, as well as a suite of non-human primate parasites from which the human malaria agents evolved. despite the significance of these parasites for global health, little information is available about their ecology in multi-host communities. primates were investigated in kibale national park, uganda, where ecological relationships among host species are well characterized. blood samples were examined for ...201323603520
chimpanzee-red colobus encounter rates show a red colobus population decline associated with predation by chimpanzees at ngogo.chimpanzees (pan troglodytes) hunt various primates, but concentrate on red colobus monkeys (piliocolobus spp.) wherever the two species are sympatric. the extraordinarily large ngogo chimpanzee community in kibale national park, uganda, preys heavily on the local population of red colobus (p. tephrosceles). census data showed a steep decline in this population in the center of the chimpanzees' home range between 1975 and 2007 [lwanga et al., 2011; teelen, 2007b]. given no obvious change in food ...201323775942
redtail and red colobus monkeys show intersite urinary cortisol concentration variation in kibale national park, uganda.non-invasive measurement of urinary cortisol is a proven method of evaluating the impact of environmental stressors on wild primates. variation in cortisol concentrations can reflect physiological stress, and prolonged elevation of circulating cortisol can significantly affect individual and population-level health. in a previous study, we found that urinary cortisol concentrations in grey-cheeked mangabeys (lophocebus albigena) were higher at a highly disturbed site (mainaro) in kibale national ...201527293691
comparative ecology of cercocebus albigena (gray) and cercocebus torquatus (kerr) in rio muni, west africa. 19684972700
technical note: dental microwear textures of "phase i" and "phase ii" facets.the power stroke of mastication has been traditionally divided into two parts, one which precedes centric occlusion, and the other which follows it-"phase i" and "phase ii," respectively. recent studies of primate mastication have called into question the role of phase ii in food processing, as they have found little muscle activity or accompanying bone strain following centric occlusion. that said, many researchers today look to phase ii facets to relate diet to patterns of dental microwear. th ...200818785631
dietary reconstruction of pliocene parapapio whitei from makapansgat, south africa, using dental microwear texture analysis.pliocene parapapio whitei fossils from makapansgat have yielded stable isotope values suggesting some foraging on c4 plants and possibly underground storage organs (usos). dental microwear texture analysis on pp.whitei (m 3147, mp 62, mp 223 and mp 239) from makapansgat members 3-4 is performed to examine whether tooth surface damage from mastication agrees with prior dietary inferences from isotopes. the enamel surface texture of pp. whitei is relatively complex, resembling lophocebus albigena ...201424280695
correlations between social context and fecal glucocorticoid metabolite concentrations in free-ranging female gray-cheeked mangabeys (lophocebus albigena) in kibale national park, 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 exa ...201324279175
long-term site fidelity and individual home range shifts in lophocebus albigena.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 mo ...200920376178
matching vocalizations to faces of familiar conspecifics in grey-cheeked mangabeys (lophocebus albigena).integration of information coming from several sensory modalities is crucial for communication and individual recognition in many species. in this experiment, we tested 6 grey-cheeked mangabeys with still pictures and vocalizations of familiar conspecifics. during the tests, the subjects faced 2 computer screens. pictures of different familiar conspecifics were displayed simultaneously on each screen, and the vocalizations of 1 of the 2 individuals were played. we recorded the subjects' fixation ...200919710557
reproductive tactics influence cortisol levels in individual male gray-cheeked mangabeys (lophocebus albigena).concentration of the hormone cortisol is often used as an indicator of stress, and chronically high cortisol levels are often associated with poor health. among group living animals that compete for resources, agonistic social interactions can be expected to contribute to variation in cortisol levels within and among individuals over time. reproductive tactics of males can change with individual quality, relatedness, and social structure, and affect cortisol levels. in gray-cheeked mangabey (lop ...200918996388
dental microwear texture analysis: technical microwear analysis is commonly used to infer aspects of diet in extinct primates. conventional methods of microwear analysis have usually been limited to two-dimensional imaging studies using a scanning electron microscope and the identification of apparent individual features. these methods have proved time-consuming and prone to subjectivity and observer error. here we describe a new methodological approach to microwear: dental microwear texture analysis, based on three-dimensional surf ...200616908052
socialization processes in primates: use of multivariate analyses. i: application to social development of captive mangabeys.we hypothesized that, within a primate group, socialization processes are influenced by each group member behaving according to his own social network. therefore socialization processes would differ in various social environments. in this study, we considered two main socialization processes, the acquisition of a social behavioral repertoire and the development of a network of social relationships, and consequently defined six comprehensive developmental parameters. we analyzed the variability o ...199624896681
locomotor differentiation and different skeletal morphologies in mangabeys (lophocebus and cercocebus).the postcranial morphology of the arboreal white-cheeked mangabey (lophocebus albigena) differs from that of partly terrestrial cercocebus mangabeys (c. torquatus, c. galeritus). its humerus has a reduced greater tuberosity, weak muscular insertions on the humeral shaft, less salient trochlear keels, a thinner diaphysis and less retroflexed medial epicondyle. the femur of l. albigena is characterized by a lowered greater trochanter, a thinner shaft, a flattened distal epiphysis and a wide and sh ...19968953746
the functional significance of primate mandibular form.a stress analysis of the primate mandible suggests that vertically deep jaws in the molar region are usually an adaptation to counter increased sagittal bending stress about the balancing-side mandibular corpus during unilateral mastication. this increased bending stress about the balancing side is caused by an increase in the amount of balancing-side muscle force. furthermore, this increased muscle force will also cause an increase in dorso-ventral shear stress along the mandibular symphysis. s ...1979458862
mangabey(cercocebus albigena). social organization and population density in relation to food use and are presented on the feeding behavior and activities of mangabeys (cercocebus albigena) in the ngogo study area, kibale forest, uganda. mangabeys spend 47% of activity observations feeding, 27% moving, and the remainder of the activity observations is accounted for by grooming, playing, vocalizing, copulating, etc. feeding on fruit constitutes 58% of feeding records, arthropods 25%, young leaves and flowers 10%, cambium 5% and rare and unidentified items 2%. 29 tree species are used as sour ...1979118905
cranial vault thickness in primates: homo erectus does not have uniquely thick vault bones.extremely thick cranial vaults have been noted as a diagnostic characteristic of homo erectus since the first fossil of the species was identified, but relatively little work has been done on elucidating its etiology or variation across fossils, living humans, or extant non-human primates. cranial vault thickness (cvt) is not a monolithic trait, and the responsiveness of its layers to environmental stimuli is unknown. we obtained measurements of cranial vault thickness in fossil hominins from th ...201626767964
taxonomic assessment of the allopatric gray-cheeked mangabey (cercocebus albigena) and black mangabey (c. aterrimus): comparative socioecological data and the species concept.a brief review of past taxonomic assessments of the allopatric gray-cheeked mangabey (cercocebus albigena) and the black mangabey (cercocebus aterrimus) is presented. on the basis of pelage, cranial, and biomolecular morphology, aterrimus and albigena have been lumped together in the same species-group, superspecies, subgenus, or species by various systematists over the years. a comparison of the available socioecological data on the two forms supports their close taxonomic association, as they ...198731973509
the socioecology of the black mangabey (cercocebus aterrimus) near lake tumba, zaire.socioecological data were gathered in a two-year study of black mangabey monkeys in a secondary forest on the west bank of lake tumba, zaire. the mangabeys of the study area lived in multi-male, multi-female groups numbering between 14 and 19 individuals. they were completely arboreal, fed mostly on fruit and nuts, and frequently were associated with other species of arboreal monkeys. their predators were human hunters and the crowned hawk-eagle. the primary vocalizations of black mangabeys were ...198731973502
maternal care in free-ranging arboreal grey-cheeked mangabeys (lophocebus albigena johnstoni) in kibale national park, uganda.maternal styles have been intensively studied in a variety of terrestrial species of primates, but far less in arboreal species. however, to have a balanced view of the evolution of maternal care, it is necessary to investigate this behaviour in the context of habitat. here, we investigate whether the mother's parity, age and dominance rank, as well as the infant's age and sex, influence maternal care and mother-infant proximity in arboreal grey-cheeked mangabeys (lophocebus albigena). we observ ...201931230043
group movements in response to competitors' calls indicate conflicts of interest between male and female grey-cheeked mangabeys.long-distance vocalizations mediate spacing patterns by allowing groups to choose whether to draw close enough to a neighbor to initiate a short-range interaction. it is unclear, however, whether the patterning of calls and the resulting movements are invariant or change in response to social and ecological variables. in this study, we compare the impact of long-distance calls on neighboring groups' movements in two populations of grey-cheeked mangabeys (lophocebus albigena) in uganda, which dif ...201830281808
influence of availability of perches on the behavioral well-being of captive, group-living mangabeys.environmental enrichment is expected to increase the well-being of animals. changes in well-being can be measured by variations in behavioral patterns. this study reports on behavioral changes induced, in arboreal monkeys, by progressively increasing the number of perches, from none to five, in an "experimental cage." a cage equipped with five perches was used as the control cage. the behaviors of a group of seven gray-cheeked mangabeys in the control cage and in the "experimental" cage were com ...199631918475
mangabey (cercocebus albigena) population density, group size, and ranging: a twenty-year comparison.mangabey groups studied in the kibale forest reserve, uganda, in 1971 were studied again in 1991 using similar data collection protocols. the results were used to assess the effect of group size on activity budgets and travel costs, and to document the effects of habitat changes on mangabey density and demography. larger mangabey groups traveled longer distances per day than smaller groups. time budgets were less clearly influenced by group size. mangabey population density increased over the 20 ...199431936918
ontogenic development of dyadic social relationships: assessing individual roles.socialization processes lead to creation and differentiation of social relationships. it is often difficult to qualify them, especially due to ontogenic changes of social behavior. in this paper, an attempt is made to assess the role of each partner in a dyad by defining the quality of their overall relationship. a social investment index (sii) was devised to describe these roles throughout ontogeny. sii is expressed as (g% - r%)/2, where g% and r% represent the difference between the sum of coh ...198331991951
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