| the intestinal parasites of a community of feral chimpanzees, pan troglodytes schweinfurthii. | fecal specimens from 32 champanzees living in gombe national park, tanzania, were examined. six species of helminths and 2 species of ciliates were found: probstmayris gombensis file (in press), strongyloides fuelleborni von linstow 1905, necator sp., oesophagostomum sp., abbreviata caucasica von linstow 1902, trichuris sp., troglodytella abrassarti brumpt and joyeux 1921, and an unidentified ciliate. none of the parasitic infections were heavy. this is the first such survey of the chimpanzee in ... | 1976 | 817011 |
| body weights of wild chimpanzees (pan troglodytes schweinfurthii) of the mahale mountains national park, tanzania. | ten male and nine female habituated chimpanzees (pan troglodytes schweinfurthii) in the kasoje area of the mahale mountains national park, tanzania, were weighed intermittently between december 1973 and march 1980 by luring them up a rope hung on a spring balance: six adult males averaged 42.0 kg and eight adult females 35.2 kg. seasonal change in body weight was recognized at least partially; body weights tended to decrease in the later part of the wet season presumably because of food shortage ... | 1987 | 3578495 |
| paternity exclusion in a community of wild chimpanzees using hypervariable simple sequence repeats. | we report the use of hypervariable simple sequence repeat (ssr) nuclear loci to study paternity in a community of wild chimpanzees (pan troglodytes schweinfurthii) in gombe national park, tanzania. all 43 living members of a habituated community were sampled and 35 were genotyped at 8 ssr loci using dna amplified from hair. paternity exclusions were performed for 25 chimpanzees including 10 for whom the mother was also genotyped. in each case 12-20 males were potential fathers based on their age ... | 1994 | 7952327 |
| patterns of predation by chimpanzees on red colobus monkeys in gombe national park, 1982-1991. | predatory patterns in wild chimpanzees are important evidence in the continuing debate about the role of hunting in the behavior of early hominids. data are presented on the predator-prey ecology of red colobus monkeys colobus badius tephrosceles) and chimpanzees (pan troglodytes schweinfurthii) in gombe national park, tanzania, from 1982 through 1991. during this period chimpanzees were observed to kill 429 mammalian prey items, 350 of which were red colobus. hunts were undertaken by chimpanzee ... | 1994 | 8085613 |
| a survey of reproductive parameters in the free-ranging chimpanzees of gombe national park. | this study is a review of reproductive records for chimpanzees (pan troglodytes schweinfurthii) living in gombe national park, tanzania, between 1964 and 1994. females exhibited their first full anogenital swelling at approximately 10.8 years of age. duration of adolescent infertility averaged 2.37 years, with first conception occurring at 12.7 years and first parturition at 13.3 years. the menstrual cycles of young nulliparous females were significantly longer than those of older multiparous fe ... | 1997 | 9155740 |
| the geographic apportionment of mitochondrial genetic diversity in east african chimpanzees, pan troglodytes schweinfurthii. | this study is a geographically systematic genetic survey of the easternmost subspecies of chimpanzee, pan troglodytes schweinfurthii. dna was noninvasively collected in the form of shed hair from chimpanzees of known origin in uganda, rwanda, tanzania, and zaïre. two hundred sixty-two dna sequences from hypervariable region 1 of which of the mitochondrial control region were generated. eastern chimpanzees display levels of mitochondrial genetic variation which are low and which are similar to le ... | 1997 | 9287430 |
| changes in the activity budget of cycling female chimpanzees. | this study is a preliminary report on the time allocated to various activities by female wild chimpanzees (pan troglodytes schweinfurthii) during their sexual cycle. cycling females with maximal tumescence (estrous females) tended to spend more time moving than cycling females with quiescent sexual skin (anestrous females). although there was no statistically significant decrease in any specific activity that corresponded to the increase in time spent moving, feeding time did decrease in four of ... | 1998 | 9773678 |
| mahale chimpanzees: grouping patterns and cycling females. | the social system of chimpanzees (pan troglodytes schweinfurthii) is characterized by the fission-fusion of social groups. several studies have reported that females are less gregarious than males. in the current study, adult female gregariousness depended on their reproductive state. noncycling adult females (pregnant, lactating, or post reproductive) were observed in large bisexual parties less often than cycling adult females. on the other hand, cycling adult females were observed in large bi ... | 1999 | 10075434 |
| tt viruses (ttv) of non-human primates and their relationship to the human ttv genotypes. | sera from eight different non-human primate species, in total 216 samples, were analysed for the presence of tt virus (ttv) sequences. a very high incidence of ttv infection was found in sera from both common chimpanzees and pygmy chimpanzees, 48.8% and 66.7%, respectively. sequence analysis of pcr fragments from two pygmy chimpanzees and seven common chimpanzees resulted in a total of 14 different ttv sequences. phylogenetic analysis, including human ttv of all known genotypes, revealed that: ( ... | 1999 | 10501506 |
| death of a wild chimpanzee community member: possible outcome of intense sexual competition. | our observations strongly support the view that a lethal gang attack occurred against a young adult male within a wild chimpanzee (pan troglodytes schweinfurthii) community. this is the first report of such an occurrence. at least three adult male chimpanzees are believed to have been involved in the attack. this case is unusual because the attack was fatal, involved directed group aggression within a community, and was not linked to the overthrow of the alpha male. during the period before the ... | 2000 | 10941440 |
| degenerative joint disease in african great apes: an evolutionary perspective. | degenerative joint disease is investigated in the spine and major peripheral joints (shoulder, elbow, hip and knee) in samples of chimpanzees (pan troglodytes schweinfurthii; p. troglodytes troglodytes), lowland gorillas (gorilla gorilla gorilla), and bonobos (p. paniscus). the p. troglodytes schweinfurthii sample comes from gombe national park, tanzania, while the other samples are derived from museum materials originally collected in west/central africa. total data for african ape samples incl ... | 2000 | 10968928 |
| noninvasive paternity assignment in gombe chimpanzees. | the relative success of chimpanzee male mating strategies, the role of male dominance rank and the success of inbreeding avoidance behaviour can only be assessed when paternities are known. we report the probable paternities of 14 chimpanzees included in a long-term behavioural study of chimpanzees (pan troglodytes schweinfurthii) at gombe national park, tanzania. dna samples were collected noninvasively from shed hair and faeces and genotyped using 13-16 microsatellite loci characterized in hum ... | 2001 | 11380884 |
| gene flow in wild chimpanzee populations: what genetic data tell us about chimpanzee movement over space and time. | the isolation of phylogenetically distinct primate immunodeficiency viruses from at least seven wild-born, captive chimpanzees indicates that viruses closely related to hiv-1 may be endemic in some wild chimpanzee populations. the search for the chimpanzee population or populations harbouring these viruses is therefore on. this paper attempts to answer the question of whether or not such populations of chimpanzees are likely to exist at all, and, if so, where they are likely to be found. we summ ... | 2001 | 11405936 |
| sources of variation in the nesting behavior of chimpanzees (pan troglodytes schweinfurthii) in the budongo forest, uganda. | data on nesting behavior and nests of the sonso community of chimpanzees (pan troglodytes schweinfurthii) living in the budongo forest, uganda, were collected between october 1995 and december 1996. analysis of the selection of nests shows a preference for particular tree species, especially cynometra alexandri. male chimpanzees nested lower than females. day nests were found to be structurally simpler than night nests and were built in tree species used for feeding, at the same height as feedin ... | 2001 | 11536316 |
| incident of intense aggression by chimpanzees against an infant from another group in mahale mountains national park, tanzania. | we document here an unusual case of intense aggression against an infant male from another group by chimpanzees (pan troglodytes schweinfurthii) of the mahale mountains national park, in tanzania. adult males of the study group collectively attacked an unknown male infant. although an unknown female, probably the mother, tried to retrieve him, the infant was seriously injured and most likely died. during this incident, the unknown female attacked and injured two researchers. after the aggressive ... | 2002 | 12478626 |
| amplification of a complete simian immunodeficiency virus genome from fecal rna of a wild chimpanzee. | current knowledge of the genetic diversity of simian immunodeficiency virus (sivcpz) infection of wild chimpanzees (pan troglodytes) is incomplete since few isolates, mostly from captive apes from cameroon and gabon, have been characterized; yet this information is critical for understanding the origins of human immunodeficiency virus type 1 (hiv-1) and the circumstances leading to the hiv-1 pandemic. here, we report the first full-length sivcpz sequence (tan1) from a wild chimpanzee (pan troglo ... | 2003 | 12525658 |
| extraordinarily low bone mineral density in an old female chimpanzee (pan troglodytes schweinfurthii) from the mahale mountains national park. | we examined bone mineral density (bmd) of the femoral neck and lumbar vertebrae of four chimpanzee skeletons from mahale mountains national park, tanzania, and four captive ones, with a dual energy x-ray absorptiometer. the bmd of wansombo, an old female chimpanzee from mahale, was remarkably lower than the mean of the other six younger adult female chimpanzees and categorized as osteoporosis. posture, locomotion, and trunk-sacral anatomy of chimpanzees may have prevented fractures in wansombo, ... | 2003 | 12687478 |
| association between galago thomasi and pan troglodytes schweinfurthii in the kibale national park, uganda. | | 2003 | 12778909 |
| foci of endemic simian immunodeficiency virus infection in wild-living eastern chimpanzees (pan troglodytes schweinfurthii). | simian immunodeficiency virus of chimpanzees (sivcpz) is the immediate precursor to human immunodeficiency virus type 1 (hiv-1), yet remarkably, the distribution and prevalence of sivcpz in wild ape populations are unknown. studies of sivcpz infection rates in wild chimpanzees are complicated by the species' endangered status and by its geographic location in remote areas of sub-saharan africa. we have developed sensitive and specific urine and fecal tests for sivcpz antibody and virion rna (vrn ... | 2003 | 12805455 |
| [results of fecal parasitologic examination performed on a population of wild chimpanzees (pan troglodytes schweinfurthii) in uganda ]. | two hundred and fifty two stool samples from 38 chimpanzees in a natural population in western uganda were examined. almost all individuals were infected but the number of parasites detected by the two techniques used was low. significant seasonal differences were observed in prevalences. | 2003 | 12836519 |
| use of leaves to inspect ectoparasites in wild chimpanzees: a third cultural variant? | we report 26 cases of using leaves as tools with which wild chimpanzees (pan troglodytes schweinfurthii) in the sonso community, budongo forest, uganda, appeared to inspect objects removed during grooming. careful removal of potential ectoparasites and delicate lip or manual placement on leaves followed by intense visual examination characterised this behaviour. it appears to be done to judge whether either ingestion or discarding is most appropriate, the former occurring in most cases. this beh ... | 2004 | 15179558 |
| urinalysis in free-living chimpanzees (pan troglodytes schweinfurthii) in uganda. | | 2004 | 15214519 |
| dominance rank and fecal testosterone levels in adult male chimpanzees (pan troglodytes schweinfurthii) at ngogo, kibale national park, uganda. | in an attempt to describe hormone-behavior interactions in a sample of wild male chimpanzees, we quantified testosterone in 67 fecal samples obtained from 22 adult male chimpanzees at ngogo, kibale national park, uganda. a mixed-model methodology that controlled for age-class identified a significant positive association between testosterone levels and dominance rank. the results are consistent with those reported from a separate, smaller chimpanzee community in the same population in a study th ... | 2004 | 15356859 |
| manual laterality in anvil use: wild chimpanzees cracking strychnos fruits. | wild chimpanzees (pan troglodytes schweinfurthii) at gombe national park, tanzania, smash open the hard-shelled fruits of strychnos spp. on anvils of stone or woody vegetation. in this food-processing task, most of the apes show exclusive use of one hand or the other, that is, strong individual hand preferences. such extreme laterality of manual functioning corresponds to level 3 on a five-level descriptive model of lateralisation that appears to reflect the increasingly skillful demands of obje ... | 1999 | 15513106 |
| parasitological analyses of the male chimpanzees (pan troglodytes schweinfurthii) at ngogo, kibale national park, uganda. | numerous intestinal parasites identified in populations of wild nonhuman primates can be pathogenic to humans. furthermore, nonhuman primates are susceptible to a variety of human pathogens. because of increasing human encroachment into previously nonimpacted forests, and the potential for disease transmission between human and nonhuman primate populations, further detailed investigations of primate ecological parasitology are warranted. for meaningful comparisons to be made, it is important for ... | 2005 | 15706587 |
| agonistic screams in wild chimpanzees (pan troglodytes schweinfurthii) vary as a function of social role. | some nonhuman primates have demonstrated the capacity to communicate about external objects or events, suggesting primate vocalizations can function as referential signals. however, there is little convincing evidence for functionally referential communication in any great ape species. here, the authors demonstrate that wild chimpanzees (pan troglodytes schweinfurthii) of budongo forest, uganda, give acoustically distinct screams during agonistic interactions depending on the role they play in a ... | 2005 | 15740431 |
| re-analysis of a human hepatitis b virus (hbv) isolate from an east african wild born pan troglodytes schweinfurthii: evidence for interspecies recombination between hbv infecting chimpanzee and human. | according to current estimates, hepatitis b virus (hbv) has infected 2 billion people worldwide and among them, 360 million suffer from chronic hbv infection. except humans, hbv or hbv-like viruses have also been isolated from different species of apes and mammals. although recombination has been described to occur extensively between different genotypes within the human hbv lineage, no recombination event has ever been reported between human and non-human primate hbv sequences. it was our objec ... | 2005 | 15777724 |
| fruit sharing between wild adult chimpanzees (pan troglodytes schweinfurthii): a socially significant event? | although food sharing is a habitual aspect of chimpanzee (pan troglodytes) life, sharing of plant foods between unrelated adults is rare. observations of such behavior have typically been interpreted as the outcome of a process by which individuals that are otherwise unable to gain access to the food manage to obtain a nutritional benefit. here we present behavioral details and an acoustic analysis regarding an observation of food sharing between unrelated adult wild chimpanzees that we suggest ... | 2005 | 15834886 |
| ethnomedicinal and bioactive properties of plants ingested by wild chimpanzees in uganda. | wild chimpanzees eat several plant species claimed by traditional healers to cure diseases. however, the behaviour leading apes to ingest these peculiar species is not clearly understood. some of the items consumed by chimpanzees have low nutritional value, and there is a growing body of evidence suggesting that health might be improved or regulated by such ingestion. observations concerning the diet and the health condition of wild chimpanzees (pan troglodytes schweinfurthii) in the kibale nati ... | 2005 | 15913933 |
| testosterone and energetics in wild chimpanzees (pan troglodytes schweinfurthii). | ovarian function in female hominoids is sensitive to both energy flux and energy balance, resulting in a reduced probability of conception during periods when a successful reproductive outcome is less likely. however, the extent to which energetic factors constrain gonadal function in male hominoids is not clear. we examined the effects of both acute and chronic variation in energy availability on urinary testosterone (t) levels in adult male chimpanzees. acute changes in energy availability, wh ... | 2005 | 15940710 |
| characterization of a novel vpu-harboring simian immunodeficiency virus from a dent's mona monkey (cercopithecus mona denti). | we report the identification of a new simian immunodeficiency virus (siv), designated sivden, in a naturally infected dent's mona monkey (cercopithecus mona denti), which was kept as pet in kinshasa, capital of the democratic republic of congo. sivden is genetically distinct from the previously characterized primate lentiviruses. analysis of the full-length genomic sequence revealed the presence of a vpu open reading frame. this gene is also found in the virus lineage of human immunodeficiency v ... | 2005 | 15956597 |
| diet and seasonal changes in sympatric gorillas and chimpanzees at kahuzi-biega national park. | based on 8 years of observations of a group of western lowland gorillas (gorilla beringei graueri) and a unit-group of chimpanzees (pan troglodytes schweinfurthii) living sympatrically in the montane forest at kahuzi-biega national park, we compared their diet and analyzed dietary overlap between them in relation to fruit phenology. data on fruit consumption were collected mainly from fecal samples, and phenology of preferred ape fruits was estimated by monitoring. totals of 231 plant foods (116 ... | 2006 | 16142424 |
| reproductive endocrinology of wild female chimpanzees (pan troglodytes schweinfurthii): methodological considerations and the role of hormones in sex and conception. | fecal and urine samples were collected from 81 female east african chimpanzees (pan troglodytes schweinfurthii) in three major study populations in gombe national park, tanzania, and budongo forest reserve and kibale national park, uganda. in this study i evaluated issues related to sample storage and assay reliability, and used these methods to investigate the significance of ovarian hormone levels in terms of conception success and sexual behavior. drying of feces proved to be an effective tec ... | 2005 | 16163723 |
| what is the role of mothers in the acquisition of termite-fishing behaviors in wild chimpanzees (pan troglodytes schweinfurthii)? | this paper explores the role of maternal influences on the acquisition of a tool-using task in wild chimpanzees (pan troglodytes schweinfurthii) in order to build on and complement previous work done in captivity. young chimpanzees show a long period of offspring dependency on mothers and it is during this period that offspring learn several important skills, especially how to and on what to forage. at gombe national park, one skill that is acquired during dependency is termite-fishing, a comple ... | 2006 | 16195914 |
| tool-use for drinking water by immature chimpanzees of mahale: prevalence of an unessential behavior. | use of leaves or sticks for drinking water has only rarely been observed during long-term study of wild chimpanzees (pan troglodytes schweinfurthii) at mahale. recently, however, we observed 42 episodes of tool-use for drinking water (73 tools and two cases of using "tool-sets") between 1999 and 2004. interestingly, all of the performers were immature chimpanzees aged from 2 to 10 years. immature chimpanzees sometimes observed the tool-using performance of others and subsequently reproduced the ... | 2006 | 16228665 |
| bioactive properties of plant species ingested by chimpanzees (pan troglodytes schweinfurthii) in the kibale national park, uganda. | we measured the biological activities of a selected sample (84 crude extracts) of 24 species eaten by wild chimpanzees (pan troglodytes schweinfurthii) in the kibale national park, western uganda, to assess their potential chemotherapeutic values. antibacterial, antimalarial, and/or antileishmania activities were observed in some crude extracts, and five of these extracts showed a significant cytotoxicity against human tumor cells. active compounds isolated from three plant parts occasionally in ... | 2006 | 16419122 |
| red-tailed monkeys (cercopithecus ascanius) hunt green pigeons (treron calva) in the kalinzu forest in uganda. | red-tailed monkeys (cercopithecus ascanius) were observed hunting green pigeons (treron calva) in the kalinzu forest in uganda. during 2 h 39 min, i observed two cases of successful hunting and one case of unsuccessful hunting in a ficus saussureana tree. red-tailed monkeys stalked the pigeons until they were within 2-3 m, and then jumped and caught them. in both successful cases, blue monkeys (c. mitis) ran to the hunting site from adjacent trees in order to poach the prey, and the red-tailed m ... | 2006 | 16467957 |
| high frequency of postcoital penis cleaning in budongo chimpanzees. | cultural or tool use behaviours are typically conducted in social or food procurement contexts where the individual interacts with conspecifics, heterospecifics or environmental features. we report on postcoital penis cleaning in chimpanzees, an activity that does not fit this pattern. in penis cleaning, leaves are employed as 'napkins' to wipe clean the penis after sex. alternatively, the same cleaning motion can be done without leaves, simply using the fingers. not all chimpanzee communities s ... | 2006 | 16912503 |
| wild chimpanzee infant urine and saliva sampled noninvasively usable for dna analyses. | in many genetic studies on the great apes, fecal or hair samples have been used as sources of dna. however, feces and hairs are difficult to collect from chimpanzee infants under 3 years of age. as alternative dna sources, we investigated the efficiency of collecting urine samples from infants compared with fecal samples, as well as the validity of the dna extracted from urine and saliva samples of well-habituated m group chimpanzees (pan troglodytes schweinfurthii) in the mahale mountains natio ... | 2007 | 17111091 |
| male coercion and the costs of promiscuous mating for female chimpanzees. | for reasons that are not yet clear, male aggression against females occurs frequently among primates with promiscuous mating systems. here, we test the sexual coercion hypothesis that male aggression functions to constrain female mate choice. we use 10 years of behavioural and endocrine data from a community of wild chimpanzees (pan troglodytes schweinfurthii) to show that sexual coercion is the probable primary function of male aggression against females. specifically, we show that male aggress ... | 2007 | 17264062 |
| etho-archaeology of manual laterality: well digging by wild chimpanzees. | we present the first indirect test of manually lateralized behaviour in non-human primates, based on wells dug for drinking water by wild chimpanzees (pan troglodytes schweinfurthii). apes at toro-semliki wildlife reserve, in uganda, dig bimanually in sandy riverbeds, leaving behind paired piles of excavated sand. the volumes of left- versus right-side piles do not differ, suggesting a lack of behavioural laterality, but this needs to be verified by further, direct observational data. | 2007 | 17505134 |
| chimpanzee deaths at mahale caused by a flu-like disease. | a flu-like disease spread among chimpanzees (pan troglodytes schweinfurthii) of the m group at mahale mountains national park, tanzania, from june to july 2006. this epizootic or epidemic killed up to 12 chimpanzees. the obvious evidence of their deaths came from finding the bodies of three infants who had previously shown some symptoms of the disease. at least one of these infants died of pneumonia. in addition, nine chimpanzees were missing after the outbreak. these individuals were assumed to ... | 2008 | 17721678 |
| morphological variation in adult chimpanzees (pan troglodytes verus) of the taï national park, côte d'ivoire. | twenty five adult chimpanzee skeletons (pan troglodytes verus) of known age and sex (15 females, 10 males) from a long-term study site in taï national park, cote d'ivoire present new data on variation. these skeletons provide a rare opportunity to measure the cranium and postcranium from the same individuals. we compare measurements and indices of the taï sample with those of relatively complete pan troglodytes schweinfurthii skeletons from gombe national park, tanzania. measurements of pan pani ... | 2008 | 17786999 |
| responses of wild chimpanzees (pan troglodytes schweinfurthii) toward seismic aftershocks in the mahale mountains national park, tanzania. | this is the first report documenting the responses of wild chimpanzees (pan troglodytes schweinfurthii) to seismic activities. during our long-term fieldwork in mahale mountains national park, tanzania, a high-intensity earthquake with a richter magnitude of 6.8 occurred at 15:19 hours local time on 5 december 2005. during the main tremor, the chimpanzees displayed the "wraa" call, "scream," and "pant bark" or "bark" vocalizations. many mild aftershocks followed the main tremor, and the wild chi ... | 2008 | 17885734 |
| diet and reproductive function in wild female chimpanzees (pan troglodytes schweinfurthii) at kibale national park, uganda. | human female reproductive function is highly sensitive to current energetic condition, indicating adaptation to modulate reproductive effort in accordance with changing ecological conditions that might favor or disfavor the production of offspring. here, we test the hypothesis that reproductive capacity in female chimpanzees is likewise limited by current energetic condition. we used 12 years of data on wild chimpanzees (pan troglodytes schweinfurthii) in the kanyawara community of kibale nation ... | 2008 | 18046778 |
| skeletal pathology in pan troglodytes schweinfurthii in kibale national park, uganda. | the ecological pressures shaping chimpanzee anatomy and behavior are the subject of much discussion in primatology and paleoanthropology, yet empirical data on fundamental parameters including body size, morbidity, and mortality are rare for wild chimpanzees. here, we present skeletal pathology and body size data for 20 (19 crania, 12 postcrania) chimpanzees (pan troglodytes schweinfurthii) from kibale national park, uganda. we compare these data with other east african populations, especially g ... | 2008 | 18067120 |
| geophagy: soil consumption enhances the bioactivities of plants eaten by chimpanzees. | geophagy, the deliberate ingestion of soil, is a widespread practice among animals, including humans. although some cases are well documented, motivations and consequences of this practice on the health status of the consumer remain unclear. in this paper, we focused our study on chimpanzees (pan troglodytes schweinfurthii) of the kibale national park, uganda, after observing they sometimes ingest soil shortly before or after consuming some plant parts such as leaves of trichilia rubescens, whic ... | 2008 | 18188538 |
| functional ecology and evolution of hominoid molar enamel thickness: pan troglodytes schweinfurthii and pongo pygmaeus wurmbii. | the divergent molar characteristics of pan troglodytes and pongo pygmaeus provide an instructive paradigm for examining the adaptive form-function relationship between molar enamel thickness and food hardness. although both species exhibit a categorical preference for ripe fruit over other food objects, the thick enamel and crenulated occlusal surface of pongo molar teeth predict a diet that is more resistant to deformation (hard) and fracture (tough) than the diet of pan. we confirm these predi ... | 2008 | 18243275 |
| the influence of age on fecal steroid hormone levels in male budongo forest chimpanzees (pan troglodytes schweinfurthii). | potential interactions between age and endocrinological functioning have been understudied in wild ape populations. therefore, we examined the relationship between age and the secretion of androgens and glucocorticoids in 15 juvenile, subadult, and adult male chimpanzees (pan troglodytes schweinfurthii) free ranging in the budongo forest of uganda. one hundred and nine fecal samples were opportunistically collected, between 07:30 and 13:30 hr, during the wet season. fecal samples were preserved, ... | 2008 | 18449883 |
| social learning of nut-cracking behavior in east african sanctuary-living chimpanzees (pan troglodytes schweinfurthii). | nut cracking is restricted to communities of wild chimpanzees living in west africa, suggesting it is an example of a socially transmitted tradition. detailed study of the acquisition of nut cracking in wild chimpanzees is consistent with this conclusion. however, only 2, small-scale experiments have been carried out in captivity to explore the role of social transmission in the acquisition of this behavior. the study presented here does this with a comparatively larger, statistically viable sam ... | 2008 | 18489234 |
| hyperprogesteronemia in response to vitex fischeri consumption in wild chimpanzees (pan troglodytes schweinfurthii). | chimpanzees in gombe national park consume fruits of vitex fischeri during a short annual fruiting season. this fruit species is a member of a genus widely studied for phytoestrogen composition and varied physiological effects. one particularly well-studied species, v. agnus-castus, is noted for its documented effects on female reproductive function, evidenced in increased progesterone levels and consequent regulation of luteal function. we examined reproductive hormone levels in both male and f ... | 2008 | 18646183 |
| food material properties and mandibular load resistance abilities in large-bodied hominoids. | numerous comparative studies have sought to demonstrate a functional link between feeding behavior, diet, and mandibular form in primates. in lieu of data on the material properties of foods ingested and masticated, many investigators have relied on qualitative dietary classifications such as "folivore" or "frugivore." here we provide the first analysis of the relationship between jaw form, dietary profiles, and food material properties in large-bodied hominoids. we employed ratios of area momen ... | 2008 | 18656244 |
| temperature's influence on the activity budget, terrestriality, and sun exposure of chimpanzees in the budongo forest, uganda. | chimpanzee (pan troglodytes schweinfurthii) activity budget, terrestriality, and sun exposure were found to be influenced by the immediate environmental temperature. thirty adult chimpanzees in the budongo forest, uganda, were observed for 247 h. temperatures in the shade and sun, sky cover, sun exposure, activity, and terrestriality were recorded at 5-min intervals at <15 m from the center of the party. terrestriality frequency was 26.5% for females and 41.5% for males. terrestriality and resti ... | 2009 | 19012327 |
| urinary c-peptide tracks seasonal and individual variation in energy balance in wild chimpanzees. | c-peptide of insulin presents a promising new tool for behavioral ecologists that allows for regular, non-invasive assessment of energetic condition in wild animals. c-peptide is produced on an equimolar basis with insulin, thus is indicative of the body's response to available glucose and, with repeated measurement, provides a biomarker of energy balance. as yet, few studies have validated the efficacy of c-peptide for monitoring energy balance in wild animals. here, we assess seasonal and inte ... | 2009 | 19084530 |
| wild chimpanzees (pan troglodytes schweinfurthii) distinguish between different scream types: evidence from a playback study. | when experiencing aggression from group members, chimpanzees commonly produce screams. these agonistic screams are graded signals and vary acoustically as a function of the severity of aggression the caller is facing. we conducted a series of field playback experiments with a community of wild chimpanzees in the budongo forest, uganda, to determine whether individuals could meaningfully distinguish between screams given in different agonistic contexts. we compared six subjects' responses to scre ... | 2009 | 19112583 |
| male dominance rank and reproductive success in chimpanzees, pan troglodytes schweinfurthii. | competition for fertile females determines male reproductive success in many species. the priority of access model predicts that male dominance rank determines access to females, but this model has been difficult to test in wild populations, particularly in promiscuous mating systems. tests of the model have produced variable results, probably because of the differing socioecological circumstances of individual species and populations. we tested the predictions of the priority of access model in ... | 2009 | 19498952 |
| prevalence of troglodytella abrassarti brumpt and joyeux, 1912 in wild chimpanzees (pan troglodytes schweinfurthii) at mahale mountains national park in western tanzania. | we examined stool samples for trophozoites of the entodiniomorphid ciliate troglodytella abrassarti brumpt and joyeux, 1912, from a habituated group of chimpanzees (pan troglodytes schweinfurthii) at mahale mountains national park in western tanzania. in our study, fresh fecal samples from identified individuals were collected immediately after defecation and fixed in 10% formalin. in total, 52 samples from 38 chimpanzees (61% of 62 chimpanzees in the group) were examined using a direct smear me ... | 2010 | 19799491 |
| paternity and social rank in wild chimpanzees (pan troglodytes) from the budongo forest, uganda. | we analyzed patterns of paternity and male dominance rank in the sonso community of wild east african chimpanzees (pan troglodytes schweinfurthii) in the budongo forest, uganda. our major objective was to determine whether and how social rank influenced paternity success. we successfully genotyped 52 individuals at up to nine microsatellite loci, using dna extracted from fecal samples. of 24 offspring analyzed, we identified sires for 21. paternity success was significantly correlated with socia ... | 2010 | 20033921 |
| a new entodiniomorphid ciliate, troglocorys cava n. g., n. sp., from the wild eastern chimpanzee (pan troglodytes schweinfurthii) from uganda. | troglocorys cava n. g., n. sp. is described from the feces of wild eastern chimpanzee, pan troglodytes schweinfurthii, in uganda. this new species has a spherical body with a frontal lobe, a long vestibulum, a cytoproct located at the posterior dorsal side of the body, an ovoid macronucleus, a contractile vacuole near the cytoproct, and a large concavity on the left surface of the body. buccal ciliature is non-retractable and consists of three ciliary zones: an adoral zone surrounding the vestib ... | 2010 | 20070451 |
| fecal bacterial diversity of human-habituated wild chimpanzees (pan troglodytes schweinfurthii) at mahale mountains national park, western tanzania. | although the intestinal flora of chimpanzees has not been studied, insight into this dynamic environment can be obtained through studies on their feces. we analyzed fecal samples from human-habituated, wild chimpanzees at mahale mountains national park, tanzania, and compared microbial community profiles to determine if members of the same social group were similar. between july and december 2007, we collected fresh fecal samples from 12 individuals: four juveniles, four adolescents, and four ad ... | 2010 | 20146237 |
| demographic and ecological effects on patterns of parasitism in eastern chimpanzees (pan troglodytes schweinfurthii) in gombe national park, tanzania. | from january 2006 to january 2008, we collected 1,045 fecal samples from 90 individually-recognized, free-ranging, eastern chimpanzees (pan troglodytes schweinfurthii) inhabiting gombe national park, tanzania to determine how patterns of parasitism are affected by demographic and ecological covariates. seventeen parasite species were recovered, including eight nematodes (oesophagostomum sp., necator sp., probstmayria gombensis, strongyloides fulleborni, ascaris sp., trichuris sp., abbreviata cau ... | 2010 | 20623606 |
| lc-ms analysis of androgen metabolites in serum and urine from east african chimpanzees (pan troglodytes schweinfurthii). | testosterone regulates a wide variety of behavioral and physiological traits in male vertebrates. it influences reproductive and aggressive behaviors and is used as a marker of gonadal activity. while testosterone is the primary biologically active male gonadal steroid in the blood, it is metabolized into a variety of related steroids when excreted via urine and feces. to monitor endocrinological profiles studies on wild-living animals primarily rely on non-invasively collected samples such as u ... | 2010 | 20888823 |
| the "original" hepatitis b virus of eastern chimpanzees (pan trogrodytes schweinfurthii). | little is known about hepatitis b virus (hbv) infections in chimpanzees. therefore, we investigated the prevalence of chimpanzee hbv (chhbv) infections in captive, wild born chimpanzees in the sanctuary on ngamba island, uganda and one sample from a wild free ranging chimpanzee. in one third of the plasma samples (32.4%; 12/37) we detected antibodies to hepatitis b (core) antigen. amongst those individuals hbv dna was detected in one captive wild born and the wild chimpanzee. in contrast to the ... | 2010 | 20970465 |
| the costs of dominance: testosterone, cortisol and intestinal parasites in wild male chimpanzees. | abstract: | 2010 | 21143892 |
| a direct comparison of scan and focal sampling methods for measuring wild chimpanzee feeding behaviour. | focal sampling is the most accurate method for measuring primate activity budgets but is sometimes impractical. an alternative is scan sampling, in which the behaviour of the group is recorded at regular intervals. the simplest technique is to record whether at least 1 animal is engaged in the behaviour of interest. by direct comparison with focal data collected simultaneously on the same population, we assess the validity of this simple group level sampling method for studying chimpanzee (pan t ... | 2010 | 21196752 |
| characterization of a new simian immunodeficiency virus strain in a naturally infected pan troglodytes troglodytes chimpanzee with aids related symptoms. | data on the evolution of natural siv infection in chimpanzees (sivcpz) and on the impact of siv on local ape populations are only available for eastern african chimpanzee subspecies (pan troglodytes schweinfurthii), and no data exist for central chimpanzees (pan troglodytes troglodytes), the natural reservoir of the ancestors of hiv-1 in humans. here, we report a case of naturally-acquired sivcpz infection in a p.t.troglodytes chimpanzee with clinical and biological data and analysis of viral ev ... | 2011 | 21232091 |
| campylobacter troglodytis sp. nov., isolated from feces of human-habituated wild chimpanzees (pan troglodytes schweinfurthii) in tanzania. | the transmission of simian immunodeficiency and ebola viruses to humans in recent years has heightened awareness of the public health significance of zoonotic diseases of primate origin, particularly from chimpanzees. in this study, we analyzed 71 fecal samples collected from 2 different wild chimpanzee (pan troglodytes) populations with different histories in relation to their proximity to humans. campylobacter spp. were detected by culture in 19/56 (34%) group 1 (human habituated for research ... | 2011 | 21278267 |
| a retrospective analysis of factors correlated to chimpanzee (pan troglodytes schweinfurthii) respiratory health at gombe national park, tanzania. | infectious disease and other health hazards have been hypothesized to pose serious threats to the persistence of wild ape populations. respiratory disease outbreaks have been shown to be of particular concern for several wild chimpanzee study sites, leading managers, and researchers to hypothesize that diseases originating from and/or spread by humans pose a substantial risk to the long-term survival of chimpanzee populations. the total chimpanzee population in gombe national park, tanzania, has ... | 2011 | 21562902 |
| high prevalence of simian immunodeficiency virus infection in a community of savanna chimpanzees. | simian immunodeficiency virus (sivcpz) has a significant negative impact on the health, reproduction and lifespan of chimpanzees; yet, the prevalence and distribution of this virus in wild-living populations is still only poorly understood. here, we show that savanna chimpanzees, who live in ecologically marginal habitats at 10 to 50-fold lower population densities than forest chimpanzees, can be infected with sivcpz at high prevalence rates. fecal samples were collected from non-habituated east ... | 2011 | 21775446 |
| diet of chimpanzees (pan troglodytes schweinfurthii) at ngogo, kibale national park, uganda, 1. diet composition and diversity. | chimpanzees (pan troglodytes) are ecologically flexible omnivores with broad diets comprising many plant and animal foods, although they mostly eat fruit (including figs). like other ecologically flexible nonhuman primates (e.g., baboons, papio spp.) with broad diets, their diets vary across habitats. much data on diets come from short studies that may not capture the range of variation, however, and data are scant on variation within habitats and populations. we present data on diet composition ... | 2011 | 22109938 |
| Frequency of removal movements during social versus self-grooming among wild chimpanzees. | Grooming was observed in 11 wild chimpanzees (Pan troglodytes schweinfurthii) in Mahale, Tanzania, and the number of removal and stroke movements and grooming duration were recorded. Removal movements were more frequent during social grooming than during self-grooming. Chimpanzees used one or both hands for grooming, and grooming using both hands was more efficient for removing small objects. Due to physical constraints, self-grooming of the arms was almost always done using only one hand. The r ... | 2011 | 21861114 |
| Diet of chimpanzees (Pan troglodytes schweinfurthii) at Ngogo, Kibale National Park, Uganda, 2. temporal variation and fallback foods. | Highly frugivorous primates like chimpanzees (Pan trogolodytes) must contend with temporal variation in food abundance and quality by tracking fruit crops and relying more on alternative foods, some of them fallbacks, when fruit is scarce. We used behavioral data from 122 months between 1995 and 2009 plus 12 years of phenology records to investigate temporal dietary variation and use of fallback foods by chimpanzees at Ngogo, Kibale National Park, Uganda. Fruit, including figs, comprised most of ... | 2011 | 22125130 |
| Androgen and androgen metabolite levels in serum and urine of East African chimpanzees (Pan troglodytes schweinfurthii): comparison of EIA and LC-MS analyses. | The primary male androgen testosterone (T) is often used as an endocrinological marker to investigate androgen-behaviour interactions in males. In chimpanzees and bonobos, studies investigating the relationship between T levels and dominance rank or aggressive behaviour have revealed contradictory results. The immunoassays used in these studies were originally developed for the measurement of steroids in serum. Their application to non-invasively collected samples, however, can lead to methodolo ... | 2011 | 21983173 |
| fitness benefits of coalitionary aggression in male chimpanzees. | coalitionary aggression occurs when at least two individuals jointly direct aggression at one or more conspecific targets. scientists have long argued that this common form of cooperation has positive fitness consequences. nevertheless, despite evidence that social bond strength (which is thought to promote coalition formation) is correlated with fitness in primates, cetaceans, and ungulates, few studies have directly examined whether coalitionary aggression improves reproductive success. we tes ... | 2012 | 23459197 |
| investigations on anopheline mosquitoes close to the nest sites of chimpanzees subject to malaria infection in ugandan highlands. | malaria parasites (plasmodium sp.), including new species, have recently been discovered as low grade mixed infections in three wild chimpanzees (pan troglodytes schweinfurthii) sampled randomly in kibale national park, uganda. this suggested a high prevalence of malaria infection in this community. the clinical course of malaria in chimpanzees and the species of the vectors that transmit their parasites are not known. the fact that these apes display a specific behaviour in which they consume p ... | 2012 | 22510395 |
| parasitology of five primates in mahale mountains national park, tanzania. | parasitological surveillance in primates has been performed using coprological observation and identification of specimens from chimpanzees (pan troglodytes schweinfurthii) in mahale mountains national park, tanzania (mahale). in this study, we conducted coprological surveillance to identify the fauna of parasite infection in five primate species in mahale: red colobus (procolobus badius tephrosceles), red-tailed monkeys (cercopithecus ascanius schmidti), vervet monkeys (cercopithecus aethiops p ... | 2012 | 22661394 |
| molecular identification of entamoeba species in savanna woodland chimpanzees (pan troglodytes schweinfurthii). | to address the molecular diversity and occurrence of pathogenic species of the genus entamoeba spp. in wild non-human primates (nhp) we conducted molecular-phylogenetic analyses on entamoeba from wild chimpanzees living in the issa valley, tanzania. we compared the sensitivity of molecular [using a genus-specific polymerase chain reaction (pcr)] and coproscopic detection (merthiolate-iodine-formaldehyde concentration) of entamoeba spp. we identified entamoeba spp. in 72 chimpanzee fecal samples ... | 2016 | 26935395 |
| neutralization properties of simian immunodeficiency viruses infecting chimpanzees and gorillas. | broadly cross-reactive neutralizing antibodies (bnabs) represent powerful tools to combat human immunodeficiency virus type 1 (hiv-1) infection. here, we examined whether hiv-1-specific bnabs are capable of cross-neutralizing distantly related simian immunodeficiency viruses (sivs) infecting central (pan troglodytes troglodytes) (sivcpzptt) and eastern (pan troglodytes schweinfurthii) (sivcpzpts) chimpanzees (n = 11) as well as western gorillas (gorilla gorilla gorilla) (sivgor) (n = 1). we foun ... | 2015 | 25900654 |
| eastern chimpanzees, but not bonobos, represent a simian immunodeficiency virus reservoir. | chimpanzees in west central africa (pan troglodytes troglodytes) are endemically infected with simian immunodeficiency viruses (sivcpzptt) that have crossed the species barrier to humans and gorillas on at least five occasions, generating pandemic and nonpandemic forms of human immunodeficiency virus type 1 (hiv-1) as well as gorilla siv (sivgor). chimpanzees in east africa (pan troglodytes schweinfurthii) are also infected with sivcpz; however, their viruses (sivcpzpts) have never been found in ... | 2012 | 22837215 |
| noninvasive tuberculosis screening in free-living primate populations in gombe national park, tanzania. | recent advances in noninvasive detection methods for mycobacterial infection in primates create new opportunities for exploring the epidemiology of tuberculosis in free-living species. chimpanzees (pan troglodytes schweinfurthii) and baboons (papio anubis) in gombe national park, tanzania, were screened for infection with pathogens of the mycobacterium tuberculosis complex using fecal is6110 pcr; none was positive. this study demonstrates the feasibility of large-scale mycobacterial screening in ... | 2016 | 26419483 |
| a comparative molecular survey of malaria prevalence among eastern chimpanzee populations in issa valley (tanzania) and kalinzu (uganda). | habitat types can affect vector and pathogen distribution and transmission dynamics. the prevalence and genetic diversity of plasmodium spp. in two eastern chimpanzee populations-kalinzu forest reserve, uganda and issa valley, tanzania-inhabiting different habitat types was investigated. as a follow up study the effect of host sex and age on infections patterns in kalinzu forest reserve chimpanzees was determined. | 2016 | 27543045 |
| strongyloides infections of humans and great apes in dzanga-sangha protected areas, central african republic and in degraded forest fragments in bulindi, uganda. | dna sequence analysis was carried out on strongyloides spp. larvae obtained from fecal samples of local humans, a wild western lowland gorilla (gorilla gorilla gorilla) and a central chimpanzee (pan troglodytes troglodytes) inhabiting dzanga-sangha protected areas (dspa), central african republic, and eastern chimpanzees (pan troglodytes schweinfurthii) living in degraded forest fragments on farmland in bulindi, uganda. from humans, both strongyloides fuelleborni and strongyloides stercoralis we ... | 2016 | 27180094 |
| do chimpanzees (pan troglodytes schweinfurthii) exhibit sleep related behaviors that minimize exposure to parasitic arthropods? a preliminary report on the possible anti-vector function of chimpanzee sleeping platforms. | great apes spend half of their lives in a nightly "nest" or sleeping platform (sp), a complex object created by modifying foliage, which functions as a stable substrate on which to sleep. of the several purported functions of sps, one hypothesis is that they protect against parasitic infection. here we investigate the role of sp site choice in avoiding molestation by arthropods. this study presents preliminary data on the insect-repellent properties of preferred sleeping tree species cynometra a ... | 2013 | 23011513 |
| chimpanzee insectivory in the northern half of uganda's rift valley: do bulindi chimpanzees conform to a regional pattern? | insects are a nutritious food source for many primates. in chimpanzees, insectivory is most prevalent among communities that manufacture tools to harvest social insects, particularly ants and termites. in contrast to other long-term study sites, chimpanzees (pan troglodytes schweinfurthii) in budongo forest and kibale national park, uganda, rarely eat insects and have small foraging tool kits, supporting speculation that infrequent insectivory--technically aided or otherwise--characterises chimp ... | 2014 | 24522970 |
| how chimpanzees integrate sensory information to select figs. | figs are keystone resources that sustain chimpanzees when preferred fruits are scarce. many figs retain a green(ish) colour throughout development, a pattern that causes chimpanzees to evaluate edibility on the basis of achromatic accessory cues. such behaviour is conspicuous because it entails a succession of discrete sensory assessments, including the deliberate palpation of individual figs, a task that requires advanced visuomotor control. these actions are strongly suggestive of domain-speci ... | 2016 | 27274803 |
| a thermodynamic comparison of arboreal and terrestrial sleeping sites for dry-habitat chimpanzees (pan troglodytes schweinfurthii) at the toro-semliki wildlife reserve, uganda. | the nightly construction of an arboreal sleeping platform (sp) has been observed among every chimpanzee's population studied to date. here, we report on bioclimatic aspects of sp site choice among dry-habitat chimpanzees (pan troglodytes schweinfurthii) at the toro-semliki wildlife reserve, uganda. we placed a portable weather monitor within 1 m of chimpanzee sps and compared the microenvironment of this site with terrestrial monitors placed 10 cm above the ground directly underneath the simulta ... | 2012 | 22553185 |
| intestinal flora modification of arthritis pattern in spondyloarthropathy. | the reactive form of spondyloarthropathy appears inducible by exposure to agents of infectious diarrhea, but do those organisms represent the tip of the iceberg, as indicated by renewed interest in gastrointestinal flora? prevalence of spondyloarthropathy (20% of chimpanzees [pan] and 28% of gorillas) is independent of subspecies and species, respectively. however, there are major differences in arthritis patterns, a characteristic shared with humans. | 2015 | 26267718 |
| tooth cusp sharpness as a dietary correlate in great apes. | mammalian molars have undergone heavy scrutiny to determine correlates between morphology and diet. here, the relationship between one aspect of occlusal morphology, tooth cusp radius of curvature (roc), and two broad dietary categories, folivory and frugivory, is analyzed in apes. the author hypothesizes that there is a relationship between tooth cusp roc and diet, and that folivores have sharper teeth than frugivores, and further test the correlation between tooth cusp roc and tooth cusp size. ... | 2014 | 24227163 |
| leaf swallowing and parasite expulsion in khao yai white-handed gibbons (hylobates lar), the first report in an asian ape species. | leaf swallowing behavior, known as a form of self-medication for the control of nematode and tapeworm infection, occurs widely in all the african great apes (pan troglodytes schweinfurthii, p. t. troglodytes, p. t. verus, p. t. vellerosus, pan paniscus, gorilla gorilla graueri), except mountain gorillas. it is also reported to occur in a similar context across a wide array of other animal taxa including, domestic dogs, wolves, brown bears, and civets. despite long-term research on asian great an ... | 2017 | 28118500 |
| how much more would knm-wt 15000 have grown? | because of its completeness, the juvenile homo ergaster/erectus knm-wt 15000 has played an important role in studies of the evolution of body form in homo. early attempts to estimate his adult body size used modern human growth models. however, more recent evidence, particularly from the dentition, suggests that he may have had a more chimpanzee-like growth trajectory. here we re-estimate his adult stature and body mass using ontogenetic data derived from four african ape taxa: pan troglodytes t ... | 2015 | 25449954 |
| the timing of spheno-occipital fusion in hominoids. | the degree of spheno-occipital fusion has been used to assign a relative age to dentally mature hominoid cranial specimens. however, a recent study of captive individuals (poe: am j phys anthropol 144 (2011) 162–165) concluded that fusion of the spheno-occipital suture in great ape taxa is of little utility for aging dentally mature individuals. in this contribution, i use dentally mature samples of extant hominoid taxa (homo sapiens, pan troglodytes schweinfurthii, gorilla gorilla gorilla, pong ... | 2015 | 25293964 |
| gastrointestinal parasite infections and self-medication in wild chimpanzees surviving in degraded forest fragments within an agricultural landscape mosaic in uganda. | monitoring health in wild great apes is integral to their conservation and is especially important where they share habitats with humans, given the potential for zoonotic pathogen exchange. we studied the intestinal parasites of wild chimpanzees (pan troglodytes schweinfurthii) inhabiting degraded forest fragments amid farmland and villages in bulindi, uganda. we first identified protozoan and helminth parasites infecting this population. sixteen taxa were demonstrated microscopically (9 protozo ... | 2017 | 28692673 |
| variation in hunting behaviour in neighbouring chimpanzee communities in the budongo forest, uganda. | hunting and sharing of meat is seen across all chimpanzee sites, with variation in prey preferences, hunting techniques, frequencies, and success rates. here, we compared hunting and meat-eating behaviour in two adjacent chimpanzee communities (pan troglodytes schweinfurthii) of budongo forest, uganda: the waibira and sonso communities. we observed consistent between-group differences in prey-species preferences and in post-hunting behaviour. sonso chimpanzees show a strong prey preference for g ... | 2017 | 28636646 |
| sagittal crest formation in great apes and gibbons. | the frequency of sagittal crest expression and patterns of sagittal crest growth and development have been documented in hominoids, including some extinct hominin taxa, and the more frequent expression of the sagittal crest in males has been traditionally linked with the need for larger-bodied individuals to have enough attachment area for the temporalis muscle. in the present study, we investigate sagittal cresting in a dentally mature sample of four hominoid taxa (pan troglodytes schweinfurthi ... | 2017 | 28418109 |
| y-chromosome structural diversity in the bonobo and chimpanzee lineages. | the male-specific regions of primate y-chromosomes (msy) are enriched for multi-copy genes highly expressed in the testis. these genes are located in large repetitive sequences arranged as palindromes, inverted-, and tandem repeats termed amplicons. in humans, these genes have critical roles in male fertility and are essential for the production of sperm. the structure of human and chimpanzee amplicon sequences show remarkable difference relative to the remainder of the genome, a difference that ... | 2016 | 27358426 |
| sex differences in object manipulation in wild immature chimpanzees (pan troglodytes schweinfurthii) and bonobos (pan paniscus): preparation for tool use? | sex differences in immatures predict behavioural differences in adulthood in many mammal species. because most studies have focused on sex differences in social interactions, little is known about possible sex differences in 'preparation' for adult life with regards to tool use skills. we investigated sex and age differences in object manipulation in immature apes. chimpanzees use a variety of tools across numerous contexts, whereas bonobos use few tools and none in foraging. in both species, a ... | 2015 | 26444011 |
| tooth wear inclination in great ape molars. | primate dietary diversity is reflected in their dental morphology, with differences in size and shape of teeth. in particular, the tooth wear angle can provide insight into a species' ability to break down certain foods. to examine dietary and masticatory information, digitized polygon models of dental casts provide a basis for quantitative analysis of wear associated with tooth attrition. in this study, we analyze and compare the wear patterns of pongo pygmaeus, gorilla gorillagorilla and pan t ... | 2017 | 28810237 |
| chimpanzees (pan troglodytes) flexibly use introduced species for nesting and bark feeding in a human-dominated habitat. | as habitat loss and fragmentation place growing pressure on endangered nonhuman primate populations, researchers find increasing evidence for novel responses in behavior. in western uganda between the budongo and bugoma forests, chimpanzees (pan troglodytes schweinfurthii) inhabit a mosaic landscape comprising forest fragments, human settlements, and agricultural land. we recorded nests and feeding evidence of unhabituated chimpanzees in this region over a 12-mo period. we found extensive eviden ... | 2017 | 28546652 |
| non-dietary analytical features of chimpanzee scats. | non-dietary aspects of ape scats such as scat weight and diameter are correlated with age and sex of defaecator for gorillas and orangutans. defaecation rates of primates, including apes, illuminate their role as primary seed dispersers. we assess if non-dietary features of scats for east african chimpanzees (pan troglodytes schweinfurthii) reveal such insights for members of the kanyawara community in kibale national park, uganda. our objective is to see if such data yield useful perspectives f ... | 2017 | 28378197 |
| applying wet sieving fecal particle size measurement to frugivores: a case study of the eastern chimpanzee (pan troglodytes schweinfurthii). | fecal particle size (fps) as quantified by wet sieving analysis is a measure of chewing efficiency relevant for the understanding of physiological adaptations and constraints in herbivores. fps has not been investigated systematically in frugivores, and important methodological problems remain. in particular, food items that are not chewed may skew estimates of fps. we address such methodological issues and also assess the influence of diet type and age on fps in wild chimpanzees. | 2017 | 28374441 |