Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| genome sequence of a chimpanzee herpesvirus and its relation to other primate alphaherpesviruses. | this study reports the complete genome sequence of chimpanzee herpesvirus (chhv), an alphaherpesvirus isolated from a chimpanzee. although closely related to human herpes simplex virus type 2 (hsv2), the level of sequence diversity confirms that chhv is sufficiently distinct to be considered a member of a different virus species rather than a variant strain of hsv2. phylogenetic comparison with other simplexviruses at several levels supports the hypothesis that hsv2 and chhv co-evolved with thei ... | 2013 | 23508549 |
| management of severe respiratory tract disease caused by human respiratory syncytial virus and streptococcus pneumoniae in captive chimpanzees (pan troglodytes). | chimpanzees (pan troglodytes) are susceptible to many viral and bacterial pathogens of human origin. this case series reports an acute outbreak of respiratory disease due to human respiratory syncytial virus and streptococcus pneumoniae in a single group of 30 captive chimpanzees. both pathogens are potentially zoonotic. the diagnosis was made antemortem and enabled a targeted response to the outbreak; but it more importantly, prompted improvements to the disease surveillance, biosecurity for ri ... | 2013 | 23505710 |
| evolutionary analysis of the contact system indicates that kininogen evolved adaptively in mammals and in human populations. | activation of the contact system leads to the cleavage of kininogen by plasma kallikrein resulting in kinin release and in the initiation of the intrinsic pathway of coagulation. proteolysis of kininogen also generates antimicrobial peptides (amps) and can be induced by diverse pathogens. thus, the contact system is regarded as a branch of innate immunity. we performed an evolutionary analysis of contact system genes by analyzing both inter- and intraspecies diversity. results indicated that mam ... | 2013 | 23505046 |
| antiprotozoal activity of khaya anthotheca, (welv.) c.d.c. a plant used by chimpanzees for self-medication. | khaya species, endemic to africa and madagascar, continues to be valuable in indigenous traditional medicine. their bitter tasting barks are decocted to treat fevers, several febrile conditions, microbial infections and worm infestations. in the budongo rain forest of western uganda, non-human primates, especially chimpanzees and baboons, have been observed to eat the bitter non-nutritious bark and occasionally the seed. | 2013 | 23501156 |
| retrotransposition of gene transcripts leads to structural variation in mammalian genomes. | retroposed processed gene transcripts are an important source of material for new gene formation on evolutionary timescales. most prior work on gene retrocopy discovery compared copies in reference genome assemblies to their source genes. here, we explore gene retrocopy insertion polymorphisms (grips) that are present in the germlines of individual humans, mice, and chimpanzees, and we identify novel gene retrocopy insertions in cancerous somatic tissues that are absent from patient-matched non- ... | 2013 | 23497673 |
| dynamics of the temporal structures of playing clusters and cliques among wild chimpanzees in mahale mountains national park. | the overall structure and temporally changing configuration of members of social play among the wild chimpanzees (pan troglodytes schweinfurthii) of mahale mountains national park, tanzania, were described on both the microscopic 'clique' levels, conceptualized as directly connected configurations through social play behavior, and macroscopic 'cluster' levels, conceptualized as indirectly connected gatherings of members of adjacent multiple cliques at the same time and space. most playing cluste ... | 2013 | 23494752 |
| classifying dogs' (canis familiaris) facial expressions from photographs. | humans accurately read other humans' emotional facial expressions. little research was found examining human ability to read dogs' expressions. cross-species research extended facial expression research to chimpanzees, and there is much research on dogs' auditory signaling to humans. to explore humans' ability to identify dogs' facial displays, photographs of a dog's face were taken under behaviorally defined conditions expected to elicit specific emotions. dog experts consistently rated these p ... | 2013 | 23485925 |
| eltrombopag: the discovery of a second generation thrombopoietin-receptor agonist. | eltrombopag (formerly sb497115) is a first-in-class, orally active thrombopoietin-receptor (tpor) agonist that stimulates megakaryocyte proliferation and differentiation. this drug is now under investigation in several conditions characterized by thrombocytopenia. | 2009 | 23480339 |
| do chimpanzee nests serve an anti-predatory function? | sleep is a vulnerable state for animals as it compromises the ability to detect predators. the evolution of shelter construction in the great apes may have been a solution to the trade-off between restorative sleep and predation-risk, which allowed a large bodied ape to sleep recumbent in a safe, comfortable spot. in this article we review the evidence of predator pressure on great apes and specifically investigate the potential influence of predation-risk on chimpanzee nesting behavior by compa ... | 2013 | 23471670 |
| a volumetric comparison of the insular cortex and its subregions in primates. | the neuronal composition of the insula in primates displays a gradient, transitioning from granular neocortex in the posterior-dorsal insula to agranular neocortex in the anterior-ventral insula with an intermediate zone of dysgranularity. additionally, apes and humans exhibit a distinctive subdomain in the agranular insula, the frontoinsular cortex (fi), defined by the presence of clusters of von economo neurons (vens). studies in humans indicate that the ventral anterior insula, including agra ... | 2013 | 23466178 |
| animal models for hepatitis c. | hepatitis c remains a global epidemic. approximately 3 % of the world's population suffers from chronic hepatitis c, which is caused by hepatitis c virus (hcv)-a positive sense, single-stranded rna virus of the flaviviridae family. hcv has a high propensity for establishing a chronic infection. if untreated chronic hcv carriers can develop severe liver disease including fibrosis, cirrhosis, and hepatocellular carcinoma (hcc). antiviral treatment is only partially effective, costly, and poorly to ... | 2013 | 23463197 |
| the origin of hepatitis c virus. | the origin of hepatitis c virus (hcv) can be conceptualised at several levels. firstly, origins might refer to its dramatic spread throughout the western world and developing countries throughout the twentieth century. as a blood-borne virus, this epidemic was fuelled by new parenteral transmission routes associated with medical treatments, immunisation, blood transfusion and more recently injecting drug use. at another level, however, origins might refer to the immediate sources of hcv associat ... | 2013 | 23463195 |
| premolar root morphology and metric variation in pan troglodytes verus. | premolar root form remains an important taxonomic character in hominin alpha taxonomy. variation in detailed aspects of root structure remains poorly characterized in extant apes. this limited comparative context hinders evaluations of the significance of root form variation in hominin systematics. using micro-computed tomography we examine morphological variation in premolars in 51 (n = 128 premolars) west african chimpanzees (pan troglodytes verus). we categorize premolar root/canal form and n ... | 2013 | 23460305 |
| response of rhesus macaques (macaca mulatta) to the body of a group member that died from a fatal attack. | among animals that form social bonds, the death of a conspecific may be a significant social event, representing the loss of an ally and resulting in disruptions to the dominance hierarchy. despite this potential biological importance, we have only limited knowledge of animals' reactions to the death of a group member. this is particularly true of responses to dead adults, as most reports describe the responses of mothers to dead infants. here, we describe in detail and provide video evidence of ... | 2012 | 23459587 |
| 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 |
| phylogenetic analysis of glucosyltransferases and implications for the coevolution of mutans streptococci with their mammalian hosts. | glucosyltransferases (gtfs) catalyze the synthesis of glucans from sucrose and are produced by several species of lactic-acid bacteria. the oral bacterium streptococcus mutans produces large amounts of glucans through the action of three gtfs. gtfd produces water-soluble glucan (wsg), gtfb synthesizes water-insoluble glucans (wig) and gtfc produces mainly wig but also wsg. these enzymes, especially those synthesizing wig, are of particular interest because of their role in the formation of denta ... | 2013 | 23457545 |
| intelligence and embodiment: a statistical mechanics approach. | evolutionary neuroscience has been mainly dominated by the principle of phylogenetic conservation, specifically, by the search for similarities in brain organization. this principle states that closely related species tend to be similar because they have a common ancestor. however, explaining, for instance, behavioral differences between humans and chimpanzees, has been revealed to be notoriously difficult. in this paper, the hypothesis of a common information-processing principle exploited by t ... | 2013 | 23454920 |
| mother-offspring transmission and age-dependent accumulation of simian foamy virus in wild chimpanzees. | simian foamy viruses (sfvs) are thought to infect virtually any adult nonhuman primate (nhp). while many data have accumulated about patterns of codivergence with their hosts and cross-species transmission events, little is known about the modalities of sfv transmission within nhp species, especially in the wild. here we provide a detailed investigation of the dynamics of sfv circulation in a wild community of western chimpanzees (pan troglodytes verus). we demonstrate that mother-offspring (ver ... | 2013 | 23449796 |
| does habitat disturbance increase infectious disease risk for primates? | many studies have suggested that ecosystem conservation protects human and wildlife populations against infectious disease. we tested this hypothesis using data on primates and their parasites. first, we tested for relationships between species' resilience to human disturbance and their parasite richness, prevalence and immune defences, but found no associations. we then conducted a meta-analysis of the effects of disturbance on parasite prevalence, which revealed no overall effect, but a positi ... | 2013 | 23448139 |
| prevalence of multinucleotide replacements in evolution of primates and drosophila. | evolution of sequences mostly involves independent changes at different sites. however, substitutions at neighboring sites may co-occur as multinucleotide replacement events (mnrs). here, we compare noncoding sequences of several species of primates, and of three species of drosophila fruit flies, in a phylogenetic analysis of the replacements that occurred between species at nearby nucleotide sites. both in primates and in drosophila, the frequency of single-nucleotide replacements is substanti ... | 2013 | 23447710 |
| mutational tail loss is an evolutionary mechanism for liberating marapsins and other type i serine proteases from transmembrane anchors. | human and mouse marapsins (prss27) are serine proteases preferentially expressed by stratified squamous epithelia. however, mouse marapsin contains a transmembrane anchor absent from the human enzyme. to gain insights into physical forms, activities, inhibition, and roles in epithelial differentiation, we traced tail loss in human marapsin to a nonsense mutation in an ancestral ape, compared substrate preferences of mouse and human marapsins with those of the epithelial peptidase prostasin, desi ... | 2013 | 23447538 |
| a previously undiscovered group of chimpanzees (pan troglodytes verus) is observed living in the tonkolili district of sierra leone. | a previously undocumented group of wild chimpanzees (pan troglodytes verus) was recently discovered along the pampana river in the tonkolili district of sierra leone. based on interviews from local residents (n = 6), we estimate the group size to be approximately 30 individuals. though this population does not show up in the most recent census of chimpanzees in sierra leone, it concurs with findings that indicate most of the chimpanzees in sierra leone live scattered throughout the country along ... | 2013 | 23447116 |
| monkeys perform as well as apes and humans in a size discrimination task. | whether the cognitive competences of monkeys and apes are rather similar or whether the larger-brained apes outperform monkeys in cognitive experiments is a highly debated topic. direct comparative analyses are therefore essential to examine similarities and differences among species. we here compared six primate species, including humans, chimpanzees, bonobos, gorillas (great apes), olive baboons, and long-tailed macaques (old world monkeys) in a task on fine-grained size discrimination. except ... | 2013 | 23443407 |
| facial orientation and facial shape in extant great apes: a geometric morphometric analysis of covariation. | the organization of the bony face is complex, its morphology being influenced in part by the rest of the cranium. characterizing the facial morphological variation and craniofacial covariation patterns in extant hominids is fundamental to the understanding of their evolutionary history. numerous studies on hominid facial shape have proposed hypotheses concerning the relationship between the anterior facial shape, facial block orientation and basicranial flexion. in this study we test these hypot ... | 2013 | 23441232 |
| brain response to affective pictures in the chimpanzee. | advancement of non-invasive brain imaging techniques has allowed us to examine details of neural activities involved in affective processing in humans; however, no comparative data are available for chimpanzees, the closest living relatives of humans. in the present study, we measured event-related brain potentials in a fully awake adult chimpanzee as she looked at affective and neutral pictures. the results revealed a differential brain potential appearing 210 ms after presentation of an affect ... | 2013 | 23439389 |
| anopheles moucheti and anopheles vinckei are candidate vectors of ape plasmodium parasites, including plasmodium praefalciparum in gabon. | during the last four years, knowledge about the diversity of plasmodium species in african great apes has considerably increased. several new species were described in chimpanzees and gorillas, and some species that were previously considered as strictly of human interest were found to be infecting african apes. the description in gorillas of p. praefalciparum, the closest relative of p. falciparum which is the main malignant agent of human malaria, definitively changed the way we understand the ... | 2013 | 23437363 |
| pandora's growing box: inferring the evolution and development of hominin brains from endocasts. | the brain of modern humans is an evolutionary and developmental outlier: at birth, it has the size of an adult chimpanzee brain and expands by a factor of 2 during the first postnatal year. large neonatal brain size and rapid initial growth contrast with slow maturation, which extends well into adolescence. when, how, and why this peculiar pattern of brain ontogeny evolved and how it is correlated with structural changes in the brain are key questions of paleoanthropology. because brains and the ... | 2013 | 23436646 |
| effect of a cognitive challenge device containing food and non-food rewards on chimpanzee well-being. | exploration and problem-solving are highly motivated behaviors in non-human primates, but little research has focused on whether cognitively challenging tasks can enhance primates' psychological well-being, particularly in the absence of food rewards. we evaluated whether a novel cognitive challenge device (ccd) consisting of a maze of opaque tubes enhanced the well-being of a group of six adult chimpanzees housed at zsl whipsnade zoo, uk, over a two-month period. chimpanzees had the opportunity ... | 2013 | 23436455 |
| death of the alpha: within-community lethal violence among chimpanzees of the mahale mountains national park. | chimpanzees (pan troglodytes) are capable of extreme violence. they engage in inter-group, sometimes lethal, aggression that provides the winners with an opportunity to enlarge their territory, increase their food supply and, potentially, attract more mates. lethal violence between adult males also occurs within groups but this is rare; to date, only four cases (three observed and one inferred) have been recorded despite decades of observation. in consequence, the reasons for within-group lethal ... | 2013 | 23436438 |
| gesture use by chimpanzees (pan troglodytes): differences between sexes in inter- and intra-sexual interactions. | communication and social relationships are two of the most important aspects of primate life, but few studies have focused on linking these aspects in apes. there are some shared social pressures between the two sexes (e.g., kin selection, alliance formation, and protection against attack), but there are also differences (e.g., mate selection, dispersal, and social ranking systems). the aim of this study was to identify the communication strategies of the sexes with respect to their particular c ... | 2013 | 23436383 |
| a chimpanzee skull in the devil's cave. | 2013 | 23433974 | |
| evolutionary constraints in the β-globin cluster: the signature of purifying selection at the δ-globin (hbd) locus and its role in developmental gene regulation. | human hemoglobins, the oxygen carriers in the blood, are composed by two α-like and two β-like globin monomers. the β-globin gene cluster located at 11p15.5 comprises one pseudogene and five genes whose expression undergoes two critical switches: the embryonic-to-fetal and fetal-to-adult transition. hbd encodes the δ-globin chain of the minor adult hemoglobin (hba2), which is assumed to be physiologically irrelevant. paradoxically, reduced diversity levels have been reported for this gene. in th ... | 2013 | 23431002 |
| chimpanzees' (pan troglodytes) strategic helping in a collaborative task. | many animal species cooperate, but the underlying proximate mechanisms are often unclear. we presented chimpanzees with a mutualistic collaborative food-retrieval task requiring complementary roles, and tested subjects' ability to help their partner perform her role. for each role, subjects required a different tool, and the tools were not interchangeable. we gave one individual in each dyad both tools, and measured subjects' willingness to transfer a tool to their partner as well as which tool ... | 2013 | 23426915 |
| identification of a novel polyomavirus from vervet monkeys in zambia. | to examine polyomavirus (pyv) infection in wildlife, we investigated the presence of pyvs in zambia with permission from the zambia wildlife authority. we analysed 200 dna samples from the spleens and kidneys (n = 100 each) of yellow baboons and vervet monkeys (vms) (n = 50 each). we detected seven pyv genome fragments in 200 dna samples using a nested broad-spectrum pcr method, and identified five full-length viral genomes using an inverse pcr method. phylogenetic analysis of virally encoded pr ... | 2013 | 23426354 |
| reasoning by inference: further studies on exclusion in grey parrots (psittacus erithacus). | grey parrot (psittacus erithacus) abilities for visual inferential reasoning by exclusion were tested in two experiments. the first replicated the grey parrot study of mikolasch, kotrschal, and schloegl (2011, african grey parrots (psittacus erithacus) use inference by exclusion to find hidden food. biology letters, 7, 875-877), which in turn replicated that of premack and premck (1994, levels of causal understanding in chimpanzees and children. cognition, 50, 347-362) with apes, to learn if our ... | 2013 | 23421751 |
| long-standing balancing selection in the thbs4 gene: influence on sex-specific brain expression and gray matter volumes in alzheimer disease. | the thbs4 gene encodes a glycoprotein involved in inflammatory responses and synaptogenesis. thbs4 is expressed at higher levels in the brain of humans compared with nonhuman primates, and the protein accumulates in β-amyloid plaques. we analyzed thbs4 genetic variability in humans and show that two haplotypes (hap1 and hap2) are maintained by balancing selection and modulate thbs4 expression in lymphocytes. indeed, the balancing selection region covers a predicted transcriptional enhancer. in h ... | 2013 | 23420636 |
| how the thatcher illusion reveals evolutionary differences in the face processing of primates. | face recognition in humans is a complex cognitive skill that requires sensitivity to unique configurations of eyes, mouth, and other facial features. the thatcher illusion has been used to demonstrate the importance of orientation when processing configural information within faces. transforming an upright face so that the eyes and mouth are inverted renders the face grotesque; however, when this "thatcherized" face is inverted, the effect disappears. due to the use of primate models in social c ... | 2013 | 23420511 |
| gs-9620, an oral agonist of toll-like receptor-7, induces prolonged suppression of hepatitis b virus in chronically infected chimpanzees. | direct-acting antiviral agents suppress hepatitis b virus (hbv) load, but they require life-long use. stimulation of the innate immune system could increase its ability to control the virus and have long-lasting effects after a finite regimen. we investigated the effects of immune activation with gs-9620--a potent and selective orally active small molecule agonist of toll-like receptor 7--in chimpanzees with chronic hbv infection. | 2013 | 23415804 |
| evolution of the brain and social behavior in chimpanzees. | the comparison of humans and chimpanzees is a unique way to highlight the evolutionary origins of human nature. this paper summarizes the most recent advances in the study of chimpanzee brains, cognition, and behavior. it covers the topics such as eye-tracking study, helping behavior, prefrontal wm volume increase during infancy, and fetal brain development. based on the facts, the paper proposed the "social brain hypothesis". chimpanzees are good at capturing images as a whole, while humans are ... | 2013 | 23414685 |
| multiple instances of ancient balancing selection shared between humans and chimpanzees. | instances in which natural selection maintains genetic variation in a population over millions of years are thought to be extremely rare. we conducted a genome-wide scan for long-lived balancing selection by looking for combinations of snps shared between humans and chimpanzees. in addition to the major histocompatibility complex, we identified 125 regions in which the same haplotypes are segregating in the two species, all but two of which are noncoding. in six cases, there is evidence for an a ... | 2013 | 23413192 |
| homo sapiens, homo neanderthalensis and the denisova specimen: new insights on their evolutionary histories using whole-genome comparisons. | after a brief review of the most recent findings in the study of human evolution, an extensive comparison of the complete genomes of our nearest relative, the chimpanzee (pan troglodytes), of extant homo sapiens, archaic homo neanderthalensis and the denisova specimen were made. the focus was on non-synonymous mutations, which consequently had an impact on protein levels and these changes were classified according to degree of effect. a total of 10,447 non-synonymous substitutions were found in ... | 2012 | 23413113 |
| facial expressions in common marmosets (callithrix jacchus) and their use by conspecifics. | facial expressions have been studied mainly in chimpanzees and have been shown to be important social signals. in platyrrhine and strepsirrhine primates, it has been doubted that facial expressions are differentiated enough, or the species socially capable enough, for facial expressions to be part of their communication system. however, in a series of experiments presenting olfactory, auditory and visual stimuli, we found that common marmosets (callithrix jacchus) displayed an unexpected variety ... | 2013 | 23412667 |
| distribution of a community of mammals in relation to roads and other human disturbances in gabon, central africa. | we present the first community-level study of the associations of both roads and other human disturbances with the distribution of mammals in gabon (central africa). our study site was in an oil concession within a littoral mosaic landscape. we conducted surveys along 199 line transects and installed camera traps on 99 of these transects to document mammal presence and abundance. we used generalized linear mixed-effect models to document associations between variables related to the ecosystem (l ... | 2013 | 23410077 |
| isolation of antibodies from non-human primates for clinical use. | antibodies intended for clinical use have been isolated from non-human primates (nhp), chimpanzees (pan troglodytes) and macaques (macaca fascicularis and macaca mulatta), essentially with the use of the phage-display technology. all studies presenting such isolations have been reviewed and presented here, following the main steps of this technology, and advantages and disadvantages of nhp species were analyzed. optimization of the tolerance of chimeric nhp-human antibodies by germline humanizat ... | 2014 | 23410051 |
| humeral cross-sectional shape in suspensory primates and sloths. | studies on the cross-sectional geometry of long bones in african apes have documented that shape ratios derived from second moments of area about principle axes (e.g., imax /imin ) are often correlated with habitual locomotor behaviors. for example, humeral cross-sections tend to appear more circular in more arboreal and forelimb suspensory chimpanzees compared with terrestrial quadrupedal gorillas. these data support the hypothesis that cross-sections that are more circular in shape are adapted ... | 2013 | 23408647 |
| effects of human presence on chimpanzee nest location in the lebialem-mone forest landscape, southwest region, cameroon. | in several areas of africa, great apes experience increasing predation pressure as a result of human activities. in this study, terrestrial and arboreal nest construction among chimpanzee (pan troglodytes ellioti) populations was investigated in the lebialem-mone forest landscape (lmfl), southwest region, cameroon, to examine the anthropogenic effects on nest location. data on the height, distribution and approximate age of chimpanzee night nests were collected during two 4-week primate field su ... | 2013 | 23406888 |
| molecular evidence for the presence of rickettsia felis in the feces of wild-living african apes. | rickettsia felis is a common emerging pathogen detected in mosquitoes in sub-saharan africa. we hypothesized that, as with malaria, great apes may be exposed to the infectious bite of infected mosquitoes and release r. felis dna in their feces. | 2013 | 23405087 |
| lipopolysaccharide-induced inhibition of transcription of tlr4 in vitro is reversed by dexamethasone and correlates with presence of conserved nfκb binding sites. | engagement of toll-like receptor 4 (tlr4) by lipopolysaccharide (lps) is a master trigger of the deleterious effects of septic shock. horses and humans are considered the most sensitive species to septic shock, but the mechanisms explaining these phenomena remain elusive. analysis of tlr4 promoters revealed high similarity among lps-sensitive species (human, chimpanzee, and horse) and low similarity with lps-resistant species (mouse and rat). four conserved nuclear factor kappa b (nfκb) binding ... | 2013 | 23402753 |
| filming chimpanzee gestures. | 2013 | 23401551 | |
| human-associated staphylococcus aureus strains within great ape populations in central africa (gabon). | the risk of serious infections caused by staphylococcus aureus is well-known. however, most studies regarding the distribution of (clinically relevant) s. aureus among humans and animals took place in the western hemisphere and only limited data are available from (central) africa. in this context, recent studies focused on s. aureus strains in humans and primates, but the question of whether humans and monkeys share related s. aureus strains or may interchange strains remained largely unsolved. ... | 2012 | 23398468 |
| performance asymmetries in tool use are associated with corpus callosum integrity in chimpanzees (pan troglodytes): a diffusion tensor imaging study. | the authors examined the relationship of corpus callosum (cc) morphology and organization to hand preference and performance on a motor skill task in chimpanzees. handedness was assessed using a complex tool use task that simulated termite fishing. chimpanzees were initially allowed to perform the task wherein they could choose which hand to use (preference measure), then they were required to complete trials using each hand (performance measure). two measures were used to assess the cc: midsagi ... | 2013 | 23398443 |
| natural category discrimination in chimpanzees (pan troglodytes) at three levels of abstraction. | two adult chimpanzees were presented with a series of natural category discrimination tasks on a touch screen computer, in which the discriminations varied in degree of abstraction. at the concrete level, discriminations could be made on the basis of single perceptual features, but at the more abstract level, categories were more inclusive, containing exemplars with variant perceptual features. for instance, at the most abstract level, the chimpanzees were required to select images of animals ra ... | 2013 | 23397185 |
| a review of the medicinal potentials of plants of the genus vernonia (asteraceae). | the vernonia genus has about one thousand species and members of the genus are widely used as food and medicine. the aim of this review is to analyze published data on the ethnomedicinal, ethnoveterinary and zoopharmacognostic uses of plants of the vernonia genus. this will help to identify the state of ethnopharmacological knowledge in regard to this genus and to propose future research priorities. | 2013 | 23395623 |
| comparative analysis of the magnitude, quality, phenotype, and protective capacity of simian immunodeficiency virus gag-specific cd8+ t cells following human-, simian-, and chimpanzee-derived recombinant adenoviral vector immunization. | recombinant adenoviral vectors (rads) are the most potent recombinant vaccines for eliciting cd8(+) t cell-mediated immunity in humans; however, prior exposure from natural adenoviral infection can decrease such responses. in this study we show low seroreactivity in humans against simian- (sad11, sad16) or chimpanzee-derived (chad3, chad63) compared with human-derived (rad5, rad28, rad35) vectors across multiple geographic regions. we then compared the magnitude, quality, phenotype, and protecti ... | 2013 | 23390298 |
| the frequency of cd127(+) hepatitis c virus (hcv)-specific t cells but not the expression of exhaustion markers predicts the outcome of acute hcv infection. | t cells are exhausted and overexpress inhibitory molecules in chronic hepatitis c virus (hcv) infection. it is unclear whether this is the cause or consequence of hcv persistence. by studying serial blood and liver samples of chimpanzees during acute infection, we demonstrate that the early expression of the memory precursor marker cd127 on hcv-specific t cells, but not the expression of inhibitory molecules on those t cells or their ligands in the liver, predicts the outcome of acute infection. | 2013 | 23388706 |
| basis for cumulative cultural evolution in chimpanzees: social learning of a more efficient tool-use technique. | the evidence for culture in non-human animals has been growing incrementally over the past two decades. however, the ability for cumulative cultural evolution, with successive generations building on earlier achievements, in non-human animals remains debated. faithful social learning of incremental improvements in technique is considered to be a defining feature of human culture, differentiating human from non-human cultures. this study presents the first experimental evidence for chimpanzees' s ... | 2013 | 23383278 |
| covariation between midline cranial base, lateral basicranium, and face in modern humans and chimpanzees: a 3d geometric morphometric analysis. | previous studies showed that in modern humans the basicranium is formed of two modules: the midline cranial base and the lateral basicranium which are integrated with the face in very different ways. the study of the relationship between these structures is of prime interest in the context of hominids craniofacial evolutionary history. in this study, we aim to test if the relationship between the midline cranial base and the face on one hand and the lateral basicranium and the face on the other ... | 2013 | 23382005 |
| chimpanzees (pan troglodytes) transfer tokens repeatedly with a partner to accumulate rewards in a self-control task. | there has been extensive research investigating self-control in humans and nonhuman animals, yet we know surprisingly little about how one's social environment influences self-control. the present study examined the self-control of chimpanzees in a task that required active engagement with conspecifics. the task consisted of transferring a token back and forth with a partner animal in order to accumulate food rewards, one item per token transfer. self-control was required because at any point in ... | 2013 | 23381691 |
| animal models. advisers urge nih to scale back chimpanzee research. | 2013 | 23371988 | |
| variation in vasopressin receptor (avpr1a) expression creates diversity in behaviors related to monogamy in prairie voles. | polymorphisms in noncoding regions of the vasopressin 1a receptor gene (avpr1a) are associated with a variety of socioemotional characteristics in humans, chimpanzees, and voles, and may impact behavior through a site-specific variation in gene expression. the socially monogamous prairie vole offers a unique opportunity to study such neurobiological control of individual differences in complex behavior. vasopressin 1a receptor (v1ar) signaling is necessary for the formation of the pair bond in m ... | 2013 | 23370363 |
| from cheetahs to chimpanzees: a comparative review of the drivers of human-carnivore conflict and human-primate conflict. | human-wildlife conflict is a growing conservation threat, and is increasingly of importance to primate conservationists. despite this, relatively little work has been done to date on the drivers of human-primate conflict, especially compared to other conflict-causing taxa such as large carnivores. however, the drivers of conflict are often very similar across species, so conflict researchers can learn important lessons from work conducted on other taxa. this paper discusses 8 key factors which a ... | 2012 | 23363596 |
| attempted predation by nigeria-cameroon chimpanzees (pan troglodytes ellioti) on preuss's red colobus (procolobus preussi) in the ebo forest, cameroon. | we describe the first observation of a predation attempt by nigerian-cameroon chimpanzees (pan troglodytes ellioti) on preuss's red colobus (procolobus preussi) in the ebo forest, cameroon. the activity, which was observed for 15 min, primarily involved 1 chimpanzee and 1 red colobus individual, with a further 2 chimpanzees observing the event. although the behaviour was interrupted when we were detected by the chimpanzees, we believe that this is the first recorded observation of hunting behavi ... | 2012 | 23363592 |
| first molar eruption, weaning, and life history in living wild chimpanzees. | understanding dental development in chimpanzees, our closest living relatives, is of fundamental importance for reconstructing the evolution of human development. most early hominin species are believed to show rapid ape-like patterns of development, implying that a prolonged modern human childhood evolved quite recently. however, chimpanzee developmental standards are uncertain because they have never been based on living wild individuals. furthermore, although it is well established that first ... | 2013 | 23359695 |
| within- and between-task consistency in hand use as a means of characterizing hand preferences in captive chimpanzees (pan troglodytes). | there remain considerable questions regarding the evidence for population-level handedness in nonhuman primates when compared with humans. one challenge in comparing human and nonhuman primate handedness involves the procedures used to characterize individual handedness. studies of human handedness use consistency in hand use within and between tasks as a basis for hand preference classification. in contrast, studies of handedness in nonhuman primates use statistical criteria for classifying han ... | 2013 | 23356440 |
| comparison of the distal gut microbiota from people and animals in africa. | the gut microbiota plays a key role in the maintenance of healthy gut function as well as many other aspects of health. high-throughput sequence analyses have revealed the composition of the gut microbiota, showing that there is a core signature to the human gut microbiota, as well as variation in its composition between people. the gut microbiota of animals is also being investigated. we are interested in the relationship between bacterial taxa of the human gut microbiota and those in the gut m ... | 2013 | 23355898 |
| transposable elements: no more 'junk dna'. | since the advent of whole-genome sequencing, transposable elements (tes), just thought to be 'junk' dna, have been noticed because of their numerous copies in various eukaryotic genomes. many studies about tes have been conducted to discover their functions in their host genomes. based on the results of those studies, it has been generally accepted that they have a function to cause genomic and genetic variations. however, their infinite functions are not fully elucidated. through various mechan ... | 2012 | 23346034 |
| urinary oxytocin and social bonding in related and unrelated wild chimpanzees. | animals that maintain cooperative relationships show gains in longevity and offspring survival. however, little is known about the cognitive or hormonal mechanisms involved in cooperation. indeed, there is little support for a main hypothesis that non-human animals have the cognitive capacities required for bookkeeping of cooperative exchanges. we tested an alternative hypothesis that cooperative relationships are facilitated by an endocrinological mechanism involving oxytocin, a hormone require ... | 2013 | 23345575 |
| human life history evolution explains dissociation between the timing of tooth eruption and peak rates of root growth. | we explored the relationship between growth in tooth root length and the modern human extended period of childhood. tooth roots provide support to counter chewing forces and so it is advantageous to grow roots quickly to allow teeth to erupt into function as early as possible. growth in tooth root length occurs with a characteristic spurt or peak in rate sometime between tooth crown completion and root apex closure. here we show that in pan troglodytes the peak in root growth rate coincides with ... | 2013 | 23342167 |
| spontaneous triadic engagement in bonobos (pan paniscus) and chimpanzees (pan troglodytes). | humans are believed to have evolved a unique motivation to participate in joint activities that first develops during infancy and supports the development of shared intentionality. we conducted five experiments with bonobos (pan paniscus) and chimpanzees (pan troglodytes) (total n = 119) to assess their motivation to spontaneously participate in joint activities with a conspecific or a human. we found that even the youngest subjects preferred to interact together with a human and a toy rather th ... | 2013 | 23339560 |
| red-green color vision in three catarrhine primates. | the evolution of the red-green visual subsystem in trichromatic primates has been linked to foraging advantages, specifically the detection of either ripe fruits or young leaves amid mature foliage, and to the intraspecific socio-sexual communication, namely the signal of the male rank, the mate choice and the reproductive strategies in females. new data should be added to the debate regarding the evolution of trichromatic color vision. three catarrhine primates were observed to achieve this goa ... | 2012 | 23336029 |
| variable nk cell receptors and their mhc class i ligands in immunity, reproduction and human evolution. | natural killer (nk) cells have roles in immunity and reproduction that are controlled by variable receptors that recognize mhc class i molecules. the variable nk cell receptors found in humans are specific to simian primates, in which they have progressively co-evolved with mhc class i molecules. the emergence of the mhc-c gene in hominids drove the evolution of a system of nk cell receptors for mhc-c molecules that is most elaborate in chimpanzees. by contrast, the human system of mhc-c recepto ... | 2013 | 23334245 |
| comparative population genomics of the ejaculate in humans and the great apes. | the rapid molecular evolution of reproductive genes is nearly ubiquitous across animals, yet the selective forces and functional targets underlying this divergence remain poorly understood. humans and closely related species of great apes show strongly divergent mating systems, providing a powerful system to investigate the influence of sperm competition on the evolution of reproductive genes. this is complemented by detailed information on male reproductive biology and unparalleled genomic reso ... | 2013 | 23329688 |
| ebola virus outbreaks in africa: past and present. | ebola haemorrhagic fever (ehf) is a zoonosis affecting both human and non-human primates (nhp). outbreaks in africa occur mainly in the congo and nile basins. the first outbreaks of ehf occurred nearly simultaneously in 1976 in the democratic republic of the congo (drc, former zaire) and sudan with very high case fatality rates of 88% and 53%, respectively. the two outbreaks were caused by two distinct species of ebola virus named zaire ebolavirus (zebov) and sudan ebolavirus (sebov). the source ... | 2012 | 23327370 |
| human brain evolution: transcripts, metabolites and their regulators. | what evolutionary events led to the emergence of human cognition? although the genetic differences separating modern humans from both non-human primates (for example, chimpanzees) and archaic hominins (neanderthals and denisovans) are known, linking human-specific mutations to the cognitive phenotype remains a challenge. one strategy is to focus on human-specific changes at the level of intermediate phenotypes, such as gene expression and metabolism, in conjunction with evolutionary changes in g ... | 2013 | 23324662 |
| chimpanzees play the ultimatum game. | is the sense of fairness uniquely human? human reactions to reward division are often studied by means of the ultimatum game, in which both partners need to agree on a distribution for both to receive rewards. humans typically offer generous portions of the reward to their partner, a tendency our close primate relatives have thus far failed to show in experiments. here we tested chimpanzees (pan troglodytes) and human children on a modified ultimatum game. one individual chose between two tokens ... | 2013 | 23319633 |
| evolution of coding microsatellites in primate genomes. | microsatellites (ssrs) are highly susceptible to expansions and contractions. when located in a coding sequence, the insertion or the deletion of a single unit for a mono-, di-, tetra-, or penta(nucleotide)-ssr creates a frameshift. as a consequence, one would expect to find only very few of these ssrs in coding sequences because of their strong deleterious potential. unexpectedly, genomes contain many coding ssrs of all types. here, we report on a study of their evolution in a phylogenetic cont ... | 2013 | 23315383 |
| evolutionary time-scale of primate bocaviruses. | human bocavirus (hbov) is associated with acute gastroenteritis in humans, occurring mostly in young children and elderly people. four bocavirus genotypes (hbov1-hbov4) have been found so far. since there were no data on the contribution of hbov to gastroenteritis in russia, 1781 fecal samples collected from infants hospitalized with acute gastroenteritis in novosibirsk, russia during one year were tested for the presence of nucleic acids from hbov and three major gastrointestinal viruses (rotav ... | 2013 | 23313830 |
| human tetherin exerts strong selection pressure on the hiv-1 group n vpu protein. | hiv-1 groups m and n emerged within the last century following two independent cross-species transmissions of sivcpz from chimpanzees to humans. in contrast to pandemic group m strains, hiv-1 group n viruses are exceedingly rare, with only about a dozen infections identified, all but one in individuals from cameroon. poor adaptation to the human host may be responsible for this limited spread of hiv-1 group n in the human population. here, we analyzed the function of vpu proteins from seven grou ... | 2012 | 23308067 |
| the social function of food-associated calls in male chimpanzees. | there is an ongoing debate about the adaptive function of chimpanzee's food-associated calls. here, we tested a new hypothesis that food-associated calls in male chimpanzees function to signal that the calling individual is likely to initiate or prolong feeding. we propose that the signal functions to coordinate activities between individuals and that its ultimate function is to retain the nearby individuals in proximity. to test this hypothesis, we collected data on social and ecological correl ... | 2013 | 23307442 |
| developmental processes in face perception. | understanding the developmental origins of face recognition has been the goal of many studies of various approaches. contributions of experience-expectant mechanisms (early component), like perceptual narrowing, and lifetime experience (late component) to face processing remain elusive. by investigating captive chimpanzees of varying age, a rare case of a species with lifelong exposure to non-conspecific faces at distinctive levels of experience, we can disentangle developmental components in fa ... | 2013 | 23304435 |
| the right time to happen: play developmental divergence in the two pan species. | bonobos, compared to chimpanzees, are highly motivated to play as adults. therefore, it is interesting to compare the two species at earlier developmental stages to determine how and when these differences arise. we measured and compared some play parameters between the two species including frequency, number of partners (solitary, dyadic, and polyadic play), session length, and escalation into overt aggression. since solitary play has a role in developing cognitive and physical skills, it is no ... | 2012 | 23300765 |
| sequential tool use in great apes. | sequential tool use is defined as using a tool to obtain another non-food object which subsequently itself will serve as a tool to act upon a further (sub)goal. previous studies have shown that birds and great apes succeed in such tasks. however, the inclusion of a training phase for each of the sequential steps and the low cost associated with retrieving the longest tools limits the scope of the conclusions. the goal of the experiments presented here was, first to replicate a previous study on ... | 2012 | 23300592 |
| initiation of joint attention is associated with morphometric variation in the anterior cingulate cortex of chimpanzees (pan troglodytes). | in developing human children, joint attention (ja) is an important preverbal skill fundamental to the development of language. poor ja skills have been described as a behavioral risk factor for some neurodevelopmental disorders, such as autism spectrum disorder. it has been hypothesized that the anterior cingulate cortex (acc) plays an important role in the development of ja in human children. here, we tested whether the morphometry and lateralization of the acc differed between chimpanzees that ... | 2013 | 23300067 |
| diurnal variation in nutrients and chimpanzee foraging behavior. | primate feeding behavior varies over long (e.g., weekly, seasonally, yearly) and short (e.g., hourly) scales of time due to changes in resource availability and the nutritional composition of foods. while the factors that affect long-term changes in feeding behavior have received considerable attention, few data exist regarding what drives variability in feeding behavior over the course of a single day. to address this problem, we investigated diurnal variation in chimpanzee feeding on the leave ... | 2013 | 23300012 |
| hepatitis b virus hepatotropism is mediated by specific receptor recognition in the liver and not restricted to susceptible hosts. | the human hepatitis b virus (hbv) causes acute and chronic infections in humans and chimpanzees. hbv infects its hosts at minimal inoculation doses and replicates exclusively in hepatocytes. the viral determinants for the pronounced species specificity and the high efficacy to address hepatocytes in vivo are unknown. previous findings showed that n-terminally myristoylated peptides constituting a receptor binding domain of the hbv large envelope (l)-protein block hbv entry in vitro and in vivo. ... | 2013 | 23292963 |
| chimpanzee gb virus c and gb virus a e2 envelope glycoproteins contain a peptide motif that inhibits human immunodeficiency virus type 1 replication in human cd4⁺ t-cells. | gb virus type c (gbv-c) is a lymphotropic virus that can cause persistent infection in humans. gbv-c is not associated with any disease, but is associated with reduced mortality in human immunodeficiency virus type 1 (hiv-1)-infected individuals. related viruses have been isolated from chimpanzees (gbv-ccpz) and from new world primates (gb virus type a, gbv-a). these viruses are also capable of establishing persistent infection. we determined the nucleotide sequence encoding the envelope glycopr ... | 2013 | 23288422 |
| structural, phylogenetic and docking studies of d-amino acid oxidase activator (daoa), a candidate schizophrenia gene. | schizophrenia is a neurodegenerative disorder that occurs worldwide and can be difficult to diagnose. it is the foremost neurological disorder leading to suicide among patients in both developed and underdeveloped countries. d-amino acid oxidase activator (daoa), also known as g72, is directly implicated in the glutamateric hypothesis of schizophrenia. it activates d-amino acid oxidase, which oxidizes d-serine, leading to modulation of the n-methyl-d-aspartate receptor. | 2013 | 23286827 |
| where are we in the justification of research involving chimpanzees? | on december 15, 2011, the institute of medicine (iom) committee on the use of chimpanzees in biomedical and behavioral research issued a final report commissioned by the national institutes of health (nih). it changed the landscape of discussion about the necessity of using chimpanzees in research. the committee advanced three principles of scientifically warranted research on chimpanzees, but nih's statement of task provided inadequate opportunity for the committee to investigate moral problems ... | 2012 | 23285792 |
| a modular mind? a test using individual data from seven primate species. | it has long been debated whether the mind consists of specialized and independently evolving modules, or whether and to what extent a general factor accounts for the variance in performance across different cognitive domains. in this study, we used a hierarchical bayesian model to re-analyse individual level data collected on seven primate species (chimpanzees, bonobos, orangutans, gorillas, spider monkeys, brown capuchin monkeys and long-tailed macaques) across 17 tasks within four domains (inh ... | 2012 | 23284816 |
| a new isolation with migration model along complete genomes infers very different divergence processes among closely related great ape species. | we present a hidden markov model (hmm) for inferring gradual isolation between two populations during speciation, modelled as a time interval with restricted gene flow. the hmm describes the history of adjacent nucleotides in two genomic sequences, such that the nucleotides can be separated by recombination, can migrate between populations, or can coalesce at variable time points, all dependent on the parameters of the model, which are the effective population sizes, splitting times, recombinati ... | 2012 | 23284294 |
| investigating the relationship of dna methylation with mutation rate and allele frequency in the human genome. | dna methylation, which mainly occurs at cpg dinucleotides, is a dynamic epigenetic regulation mechanism in most eukaryotic genomes. it is already known that methylated cpg dinucleotides can lead to a high rate of c to t mutation at these sites. however, less is known about whether and how the methylation level causes a different mutation rate, especially at the single-base resolution. | 2012 | 23281708 |
| ecological volatility and human evolution: a novel perspective on life history and reproductive strategy. | humans are characterized by a suite of traits that seem to differentiate them profoundly from closely related apes such as the gorilla, chimpanzee, and orang-utan. these traits include longevity, cooperative breeding, stacking of offspring, lengthy maturation, and a complex life-course profile of adiposity. when, how, and why these traits emerged during our evolutionary history is currently attracting considerable attention. most approaches to life history emphasize dietary energy availability a ... | 2012 | 23280924 |
| the real females of human evolution. | when "woman-the-gatherer" was first proposed as a counter to "man-the-hunter," we were only beginning to understand the many faces of primate females. in ensuing decades we have learned about the skills and talents of female chimpanzees in tool using, hunting, and transmitting behaviors from one generation to the next as teachers, and across space as newcomers to neighboring communities. the perspective of evolutionary time highlights the continuity of female lives from the origin of mammals to ... | 2012 | 23280923 |
| tree climbing and human evolution. | paleoanthropologists have long argued--often contentiously--about the climbing abilities of early hominins and whether a foot adapted to terrestrial bipedalism constrained regular access to trees. however, some modern humans climb tall trees routinely in pursuit of honey, fruit, and game, often without the aid of tools or support systems. mortality and morbidity associated with facultative arboreality is expected to favor behaviors and anatomies that facilitate safe and efficient climbing. here ... | 2013 | 23277565 |
| molecular anthropology and the subversion of paleoanthropology: an example of "the emperor's clothes" effect? | although the birth of "molecular systematics" may date to the turn of the twentieth century, the discipline did not gain momentum until the 1960s, when most paleoanthropologists believed that humans were distantly related to a great ape group (chimpanzee, gorilla, orangutan), within which the african apes were most closely related. from the beginning, interpretation of molecular data, initially protein immunoreactivity, conflicted with the interpretation of morphological data by favoring a human ... | 2012 | 23272601 |
| placental invasion, preeclampsia risk and adaptive molecular evolution at the origin of the great apes: evidence from genome-wide analyses. | recent evidence from chimpanzees and gorillas has raised doubts that preeclampsia is a uniquely human disease. the deep extravillous trophoblast (evt) invasion and spiral artery remodeling that characterizes our placenta (and is abnormal in preeclampsia) is shared within great apes, setting homininae apart from hylobatidae and old world monkeys, which show much shallower trophoblast invasion and limited spiral artery remodeling. we hypothesize that the evolution of a more invasive placenta in th ... | 2012 | 23266291 |
| use of gesture sequences in captive chimpanzee (pan troglodytes) play. | this study examined the use of sensory modalities relative to a partner's behavior in gesture sequences during captive chimpanzee play at the chimpanzee and human communication institute. we hypothesized that chimpanzees would use visual gestures toward attentive recipients and auditory/tactile gestures toward inattentive recipients. we also hypothesized that gesture sequences would be more prevalent toward unresponsive rather than responsive recipients. the chimpanzees used significantly more a ... | 2013 | 23263709 |
| analysis of compensatory substitution and gene evolution on the magea/csag-palindrome of the primate x chromosomes. | the human x chromosome contains a large number of inverted repeat dna palindromes. although arbitrary substitutions destroyed the inverted repeat structure of magea/csag-palindrome during the evolutionary process of the primates, most of the substitutions are compensatory. using maximum parsimony, it is demonstrated that the compensatory substitutions are prone to occur between bases with similar structures on the human, chimpanzee and orangutan magea/csag-palindromes. furthermore, it is found t ... | 2013 | 23257410 |
| developmental patterns of chimpanzee cerebral tissues provide important clues for understanding the remarkable enlargement of the human brain. | developmental prolongation is thought to contribute to the remarkable brain enlargement observed in modern humans (homo sapiens). however, the developmental trajectories of cerebral tissues have not been explored in chimpanzees (pan troglodytes), even though they are our closest living relatives. to address this lack of information, the development of cerebral tissues was tracked in growing chimpanzees during infancy and the juvenile stage, using three-dimensional magnetic resonance imaging and ... | 2013 | 23256194 |
| single real-time reverse transcription-pcr assay for detection and quantification of genetically diverse hiv-1, sivcpz, and sivgor strains. | although antiretroviral treatment availability has improved, the virological monitoring of patients remains largely uneven across regions. in addition, viral quantification tests are suffering from human immunodeficiency virus type 1 (hiv-1) genetic diversity, fueled by the emergence of new recombinants and of lentiviruses from nonhuman primates. we developed a real-time reverse transcription-pcr (rt-pcr) assay that is relatively inexpensive and able to detect and quantify all circulating forms ... | 2013 | 23254130 |