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the large-scale distribution of somatic mutations in cancer genomes.recently, the genome sequences from several cancers have been published, along with the genome from a noncancer tissue from the same individual, allowing the identification of new somatic mutations in the cancer. we show that there is significant variation in the density of mutations at the 1-mb scale within three cancer genomes and that the density of mutations is correlated between them. we also demonstrate that the density of mutations is correlated to that in the germline, as measured by the ...201221953857
the visual strategy specific to humans among hominids: a study using the gap-overlap paradigm.although an extensive body of literature exists on the cognitive underpinnings of gaze movements in macaques and humans, few studies have investigated this topic from a broader evolutionary perspective. this study used the gap-overlap paradigm to examine the timing of the gaze movements by four hominid species: humans, chimpanzees, gorillas, and orangutans. the saccade latency involved in shifting the gaze from central to peripheral stimuli was measured and compared under two conditions, gap and ...201121951519
spontaneous abortion and preterm labor and delivery in nonhuman primates: evidence from a captive colony of chimpanzees (pan troglodytes).preterm birth is a leading cause of perinatal mortality, yet the evolutionary history of this obstetrical syndrome is largely unknown in nonhuman primate species.201121949724
bioinformatic characterization and gene expression pattern of apoptosis inhibitor from macrobrachium rosenbergii challenged with infectious hypodermal and hematopoietic necrosis virus.apoptosis is genetically programmed cellular killing processes that execute unnecessary or infected cells. it plays an important role in embryogenesis, homeostasis, insect metamorphosis and immunity. apoptosis inhibitor (mriap) was sequenced from the freshwater giant prawn macrobrachium rosenbergii using illumina solexa genome analyzer technique. mriap consisted of 1753 base pair nucleotides encoded 535 polypeptide with an estimated molecular mass of 60 kda. mriap amino acid sequence contains ia ...201121945707
biomedical research involving chimpanzees. 201121942551
generalized relational matching by guinea baboons (papio papio) in two-by-two-item analogy problems.analogical reasoning is considered the hallmark of human reasoning, but some studies have demonstrated that language- and symbol-trained chimpanzees can also reason analogically. despite the potential adaptive value of this ability, evidence from other studies strongly suggests that other nonhuman primates do not have this capacity for analogical reasoning. in our three experiments, 6 of 29 baboons acquired the ability to perform a relational matching-to-sample (rmts) task in which pairs of shap ...201121934135
Pasteurella multocida involved in respiratory disease of wild chimpanzees.Pasteurella multocida can cause a variety of diseases in various species of mammals and birds throughout the world but nothing is known about its importance for wild great apes. In this study we isolated P. multocida from wild living, habituated chimpanzees from Taï National Park, Côte d'Ivoire. Isolates originated from two chimpanzees that died during a respiratory disease outbreak in 2004 as well as from one individual that developed chronic air-sacculitis following this outbreak. Four isolate ...201121931664
Sperm methylation profiles reveal features of epigenetic inheritance and evolution in primates.During germ cell and preimplantation development, mammalian cells undergo nearly complete reprogramming of DNA methylation patterns. We profiled the methylomes of human and chimp sperm as a basis for comparison to methylation patterns of ESCs. Although the majority of promoters escape methylation in both ESCs and sperm, the corresponding hypomethylated regions show substantial structural differences. Repeat elements are heavily methylated in both germ and somatic cells; however, retrotransposons ...201121925323
Vaccine-induced cross-genotype reactive neutralizing antibodies against hepatitis C virus.We detected cross-reactive neutralizing antibodies (NtAb) against hepatitis C virus (HCV) in chimpanzees vaccinated with HCV-1 (genotype 1a) recombinant E1/E2 envelope glycoproteins. Five vaccinated chimpanzees, protected following HCV-1 challenge, were initially studied using the heterologous H77 (genotype 1a) HCVpp assay. All animals had developed NtAb after the second vaccination; 4 animals had reciprocal titers of =200 at the time of challenge. Using genotypes 1a-6a HCV pseudoparticles (HCVp ...201121917891
expanding whole exome resequencing into non-human primates.abstract: background: complete exome resequencing has the power to greatly expand our understanding of non-human primate genomes. this includes both a better appreciation of the variation that exists in non-human primate model species, but also an improved annotation of their genomes. by developing an understanding of the variation between individuals, non-human primate models of human disease can be better developed. this effort is hindered largely by the lack of comprehensive information on s ...201121917143
redescription of enterobius (enterobius) macaci yen, 1973 (nematoda: oxyuridae: enterobiinae) based on material collected from wild japanese macaque, macaca fuscata (primates: cercopithecidae).abstract enterobius (enterobius) macaci yen, 1973 (nematoda: oxyuridae: enterobiinae) was collected from a japanese macaque, macaca fuscata, in nara and yamaguchi prefectures, honshu is., japan, for the first time. a redescription is presented along with dna sequence data. this pinworm is a typical member of the subgenus enterobius, and is characteristic in the spicule morphology, being readily distinguished from other congeners. phylogenetic analyses based on 18s ribosomal rna gene (rdna) and ...201121916620
phyloepigenomic comparison of great apes reveals a correlation between somatic and germline methylation states.we have determined methylation state differences in the epigenomes of uncultured cells purified from human, chimpanzee, and orangutan, using digestion with a methylation-sensitive enzyme, deep sequencing, and computational analysis of the sequence data. the methylomes show a high degree of conservation, but the methylation states of ~10% of cpg island-like regions differ significantly between human and chimp. the differences are not associated with changes in cg content and recapitulate the know ...201121908772
assessing the effects of cognitive experiments on the welfare of captive chimpanzees (pan troglodytes) by direct comparison of activity budget between wild and captive chimpanzees.we investigated the effects of cognitive experiments by direct comparison of activity budgets between wild and captive chimpanzees. one goal of captive management is to ensure that the activity budgets of captive animals are as similar as possible to those of their wild counterparts. however, such similarity has rarely been achieved. we compared the activity budget among three groups of chimpanzees: wild chimpanzees in bossou (guinea, n = 10), and captive chimpanzees who participated in cognitiv ...201121905060
an autosomal analysis gives no genetic evidence for complex speciation of humans and chimpanzees.there have been conflicting arguments as to what happened in the human-chimpanzee speciation event. patterson et al. (2006) proposed a hypothesis that the human-chimpanzee speciation event involved a complicated demographic process: that is, the ancestral lineages of humans and chimpanzees experienced temporal isolation followed by a hybridization event. this hypothesis stemmed from two major observations: a wide range of human-chimpanzee nucleotide divergence across the autosomal genome, and ve ...201121903679
executive function in young children and chimpanzees (pan troglodytes): evidence from a nonverbal dimensional change card sort task.in this article the authors compared chimpanzees' executive function with that of children. they developed a nonverbal dimensional change card sorting task, which indexed the development of executive function. three pairs of mother and offspring chimpanzees and 30 typically developed 5-year-old children were presented with 2 target stimuli and a test stimulus comprising 2 dimensions (size and shape) on a display; they were required to sort the test stimulus according to 1 dimension (e.g., shape) ...201121902004
Analysis of the human immunodeficiency virus type 1 M group Vpu domains involved in antagonizing tetherin.Zoonosis of chimpanzee simian immunodeficiency virus cpz to humans has given rise to both pandemic (M) and non-pandemic (O, N and P) groups of human immunodeficiency virus type-1 (HIV). These lentiviruses encode accessory proteins, including Vpu, which has been shown to reduce CD4 levels on the cell surface, as well as increase virion release from the cell by antagonizing tetherin (CD317, BST2). Here, we confirm that O group Vpus (Ca9 and BCF06) are unable to counteract tetherin or downregulate ...201121900423
context-dependent tool use in new caledonian crows.humans and chimpanzees both exhibit context-dependent tool use. that is, both species choose to use tools when food is within reach, but the context is potentially hazardous. here, we show that new caledonian crows used tools more frequently when food was positioned next to a novel model snake than when food was positioned next to a novel teddy bear or a familiar food bowl. however, the crows showed no significant difference in their neophobic reactions towards the teddy bear and the model snake ...201221900316
transmission of clonal hepatitis c virus genomes reveals the dominant but transitory role of cd8⁺ t cells in early viral evolution.the rna genome of the hepatitis c virus (hcv) diversifies rapidly during the acute phase of infection, but the selective forces that drive this process remain poorly defined. here we examined whether darwinian selection pressure imposed by cd8(+) t cells is a dominant force driving early amino acid replacement in hcv viral populations. this question was addressed in two chimpanzees followed for 8 to 10 years after infection with a well-defined inoculum composed of a clonal genotype 1a (isolate h ...201121900166
What's social about social learning?Research on social learning in animals has revealed a rich variety of cases where animals-from caddis fly larvae to chimpanzees-acquire biologically important information by observing the actions of others. A great deal is known about the adaptive functions of social learning, but very little about the cognitive mechanisms that make it possible. Even in the case of imitation, a type of social learning studied in both comparative psychology and cognitive science, there has been minimal contact be ...201121895355
Unusual feeding behavior in wild great apes, a window to understand origins of self-medication in humans: Role of sociality and physiology on learning process.Certain toxic plants are beneficial for health if small amounts are ingested infrequently and in a specific context of illness. Among our closest living relatives, chimpanzees are found to consume plants with pharmacological properties. Providing insight on the origins of human self-medication, this study investigates the role social systems and physiology (namely gut specialization) play on learning mechanisms involved in the consumption of unusual and potentially bioactive foods by two great a ...201221888922
the development of a greeting signal in wild chimpanzees.adult chimpanzees produce a unique vocal signal, the pant-grunt, when encountering higher-ranking group members. the behaviour is typically directed to a specific receiver and has thus been interpreted as a 'greeting' signal. the alpha male obtains a large share of these calls, followed by the other adult males of the group. in this study, we describe the development of pant-grunting behaviour from the first grunt-like calls of newborn babies to the fully developed pant-grunts in adults. althoug ...201121884337
natural history of camponotus ant-fishing by the m group chimpanzees at the mahale mountains national park, tanzania.the aim of this study was to provide basic data on ant-fishing behavior among the m group chimpanzees at the mahale mountains national park, tanzania. ant-fishing is a type of tool-using behavior that has been exhibited by mahale chimpanzees when feeding upon arboreal carpenter ants (camponotus spp.) since the 1970s, and is now regarded as a candidate of wild chimpanzee culture. herein, i describe in detail the features of ant-fishing shown by the mahale m group chimpanzees: (1) 2 species of cam ...201121877164
phylogenetic rate shifts in feeding time during the evolution of homo.unique among animals, humans eat a diet rich in cooked and nonthermally processed food. the ancestors of modern humans who invented food processing (including cooking) gained critical advantages in survival and fitness through increased caloric intake. however, the time and manner in which food processing became biologically significant are uncertain. here, we assess the inferred evolutionary consequences of food processing in the human lineage by applying a bayesian phylogenetic outlier test to ...201121873223
cloning and pharmacological characterization of the dog cannabinoid cb₂ receptor.comparison of human, rat and mouse cannabinoid cb(2) receptor primary sequences has shown significant divergence at the mrna and protein sequence level, raising the possibility of species specific pharmacological properties. additionally, given the importance of the dog as a non-rodent species for predicting human safety during the drug development process, we cloned the dog cb(2) receptor gene and characterized its in-vitro pharmacological properties in a recombinant expression system. a 1.1 kb ...201121871882
New vertebral and rib material point to modern bauplan of the Nariokotome Homo erectus skeleton.The double S shape of the vertebral column is one of the most important evolutionary adaptations to human bipedal locomotion, providing an optimal compromise between stability and mobility. It is commonly believed that a six element long lumbar spine facilitated the critical adoption of lumbar lordosis in early hominins, which contrasts with five lumbars in modern humans and four in chimpanzees and gorillas. This is mainly based on the juvenile Homo erectus skeleton KNM-WT 15000 from Nariokotome ...201121868059
Phase Ia Clinical Evaluation of the Plasmodium falciparum Blood-stage Antigen MSP1 in ChAd63 and MVA Vaccine Vectors.Efficacy trials of antibody-inducing protein-in-adjuvant vaccines targeting the blood-stage Plasmodium falciparum malaria parasite have so far shown disappointing results. The induction of cell-mediated responses in conjunction with antibody responses is thought to be one alternative strategy that could achieve protective efficacy in humans. Here, we prepared chimpanzee adenovirus 63 (ChAd63) and modified vaccinia virus Ankara (MVA) replication-deficient vectors encoding the well-studied P. falc ...201121862998
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 ...201121861114
A replicating cytomegalovirus-based vaccine encoding a single Ebola virus nucleoprotein CTL epitope confers protection against Ebola virus.Human outbreaks of Ebola virus (EBOV) are a serious human health concern in Central Africa. Great apes (gorillas/chimpanzees) are an important source of EBOV transmission to humans due to increased hunting of wildlife including the 'bush-meat' trade. Cytomegalovirus (CMV) is an highly immunogenic virus that has shown recent utility as a vaccine platform. CMV-based vaccines also have the unique potential to re-infect and disseminate through target populations regardless of prior CMV immunity, whi ...201121858240
where are inion and endinion? variations of the exo- and endocranial morphology of the occipital bone during hominin evolution.the occipital bone is frequently investigated in paleoanthropological studies because it has several features that help to differentiate various fossil hominin species. among these features is the separation between inion and endinion, which has been proposed to be an autapomorphic trait in (asian) homo erectus. methodologies are developed here to quantify for the first time the location of these anatomical points, and to interpret their variation due to the complex interactions between exocrani ...201121855115
Diversity and host specificity of Blastocystis in syntopic primates on Rubondo Island, Tanzania.The isolated ecosystem of Rubondo Island National Park, Tanzania is an interesting model site, inhabited by an assembly of primate species with various histories: two introduced primate species, Pantroglodytes (chimpanzee) and Colobus guereza (colobus), and a single indigenous species Chlorocebus aethiops pygerythrus (vervet monkey). Apart from important lessons for future introduction/re-introduction projects, Rubondo National Park offers a unique place to study the patterns of transmission of ...201121854778
apes in africa: the cultured chimpanzees. 201121850081
clearance of genotype 1b hepatitis c virus in chimpanzees in the presence of vaccine-induced e1-neutralizing antibodies.accumulating evidence indicates that neutralizing antibodies play an important role in protection from chronic hepatitis c virus (hcv) infection. efforts to elicit such responses by immunization with intact heterodimeric e1e2 envelope proteins have met with limited success. to determine whether antigenic sites, which are not exposed by the combined e1e2 heterodimer structure, are capable of eliciting neutralizing antibody responses, we expressed and purified each as separate recombinant proteins ...201121849281
brief communication: why sleep in a nest? empirical testing of the function of simple shelters made by wild chimpanzees.all great apes build nightly a structure ("nest" or "bed") that is assumed to function primarily as a sleeping-platform. however, several other nest function hypotheses have been proposed: antipredation, antipathogen, and thermoregulation. i tested these simple shelter functions of chimpanzee nests in an experiment for which i was the subject in fongoli, senegal. i slept 11 nights in chimpanzee nests and on the bare ground to test for differences in sleep quality, potential exposure to disease t ...201121837687
novel adenoviruses in wild primates: high genetic diversity and evidence of zoonotic transmissions.adenoviruses (advs) broadly infect vertebrate hosts including a variety of nonhuman primates (nhps). in the present study we identified advs in nhps living in their natural habitat, and, through the combination of phylogenetic analyses with information on the habitat and epidemiological settings, we detected possible horizontal transmission events between nhps and humans. wild nhps were analysed with a pan-primate adv-pcr using a degenerate nested primer set that targets the highly conserved ade ...201121835802
positive selection of apobec3de in chimpanzees has driven breadth in anti-viral activity.the apobec3 family of cytidine deaminases can inhibit the replication of retroviruses and retrotransposons. human and chimpanzee genomes encode seven apobec3 paralogs; of these, apobec3de has the greatest sequence divergence between humans and chimpanzees. here we show that even though human and chimpanzee apobec3de are very divergent, both orthologs similarly restrict ltr- and non-ltr retrotransposons (musd and alu, respectively). however, chimpanzee apobec3de also potently restricts two lentiv ...201121835794
differential prefrontal white matter development in chimpanzees and humans.a comparison of developmental patterns of white matter (wm) within the prefrontal region between humans and nonhuman primates is key to understanding human brain evolution. wm mediates complex cognitive processes and has reciprocal connections with posterior processing regions [1, 2]. although the developmental pattern of prefrontal wm in macaques differs markedly from that in humans [3], this has not been explored in our closest evolutionary relative, the chimpanzee. the present longitudinal st ...201121835623
seed predation by bonobos (pan paniscus) at kokolopori, democratic republic of the congo.we compared the feeding ecology of the hali-hali community of bonobos (pan paniscus) at kokolopori, a new field site in the democratic republic of the congo, between two periods 5 months apart. during the first study period (sp1), bonobos relied heavily on the dry seeds of guibourtia (caesalpiniaceae), mostly eaten from the ground. the second period (sp2) was characterized by high consumption of ripe tree fruit. terrestrial herbaceous vegetation (thv) contributed little to the diet in either stu ...201121830045
variability and asymmetry of the sulcal contours defining broca's area homologue in the chimpanzee brain.there has been a recent motivation to search for neuroanatomical asymmetries in non-human primates in order to provide comparative information on how the human brain is structurally organized to support specific cognitive capabilities such as language functions. in the present study, we took the opportunity to study broca's area homologue in a novel sample of 80 preserved post-mortem chimpanzee (pan troglodytes) cerebral hemispheres. consistent with the only prior study documenting the morpholog ...201121826664
spontaneous prosocial choice by chimpanzees.the study of human and primate altruism faces an evolutionary anomaly: there is ample evidence for altruistic preferences in our own species and growing evidence in monkeys, but one of our closest relatives, the chimpanzee (pan troglodytes), is viewed as a reluctant altruist, acting only in response to pressure and solicitation. although chimpanzee prosocial behavior has been reported both in observational captive studies and in the wild, thus far prosocial choice tests have failed to produce ev ...201121825175
copy number variation analysis in the great apes reveals species-specific patterns of structural variation.copy number variants (cnvs) are increasingly acknowledged as an important source of evolutionary novelties in the human lineage. however, our understanding of their significance is still hindered by the lack of primate cnv data. we performed intraspecific comparative genomic hybridizations to identify loci harboring copy number variants in each of the four great apes: bonobos, chimpanzees, gorillas, and orangutans. for the first time, we could analyze differences in cnv location and frequency in ...201121824994
use of an implantable loop recorder in the investigation of arrhythmias in adult captive chimpanzees (pan troglodytes).cardiovascular disease in general, and cardiac arrhythmias specifically, is common in great apes. however, the clinical significance of arrhythmias detected on short-duration electrocardiograms is often unclear. here we describe the use of an implantable loop recorder to evaluate cardiac rhythms in 4 unanesthetized adult chimpanzees (pan troglodytes), 1 with a history of possible syncope and 3 with the diagnosis of multiform ventricular ectopy (ventricular premature complexes) and cardiomyopathy ...201121819684
a codon substitution model that incorporates the effect of the gc contents, the gene density and the density of cpg islands of human chromosomes.abstract:201121819607
the ciliate, troglodytella abrassarti, contributes to polysaccharide hydrolytic activities in the chimpanzee colon.entodiniomorphid ciliates are intestinal protists inhabiting the colons of african great apes. the participation of intestinal entodiniomorphid ciliates in ape hindgut digestion has been proposed, but little data have been available to support the hypothesis. we measured the specific activities of carboxymethyl cellulase, xylanase, inulinase, and +¦-amylase against different polysaccharides in the feces of captive chimpanzees and evaluated the participation of the entodiniomorphid ciliate, trogl ...201121818613
why does the giant panda eat bamboo? a comparative analysis of appetite-reward-related genes among mammals.the giant panda has an interesting bamboo diet unlike the other species in the order of carnivora. the umami taste receptor gene t1r1 has been identified as a pseudogene during its genome sequencing project and confirmed using a different giant panda sample. the estimated mutation time for this gene is about 4.2 myr. such mutation coincided with the giant panda's dietary change and also reinforced its herbivorous life style. however, as this gene is preserved in herbivores such as cow and horse, ...201121818345
broad-spectrum inhibition of hiv-1 by a monoclonal antibody directed against a gp120-induced epitope of cd4.to penetrate susceptible cells, hiv-1 sequentially interacts with two highly conserved cellular receptors, cd4 and a chemokine receptor like ccr5 or cxcr4. monoclonal antibodies (mabs) directed against such receptors are currently under clinical investigation as potential preventive or therapeutic agents. we immunized balb/c mice with molecular complexes of the native, trimeric hiv-1 envelope (env) bound to a soluble form of the human cd4 receptor. sera from immunized mice were found to contain ...201121818294
functional anatomy and adaptation of male gorillas (gorilla gorilla gorilla) with comparison to male orangutans (pongo pygmaeus).great apes diversified during the miocene in old world forests. two lineages, gorillas in africa and orangutans in asia, have sexual dimorphisms of super-sized males, though they presumably diverged from a smaller common ancestor. we test the hypothesis that they increased in body mass independently and convergently, and that their many postcranial differences reflect locomotor differences. whole body dissections of five adult male gorillas and four adult male orangutans allowed quantification o ...201121809463
femoral morphology and femoropelvic musculoskeletal anatomy of humans and great apes: a comparative virtopsy study.the proximal femoral morphology of fossil hominins is routinely interpreted in terms of muscular topography and associated locomotor modes. however, the detailed correspondence between hard and soft tissue structures in the proximal femoral region of extant great apes is relatively unknown, because dissection protocols typically do not comprise in-depth osteological descriptions. here, we use computed tomography and virtopsy (virtual dissection) for non-invasive examination of the femoropelvic m ...201121809454
cross-comparison of the genome sequences from human, chimpanzee, neanderthal and a denisovan hominin identifies novel potentially compensated mutations.the recent publication of the draft genome sequences of the neanderthal and a ~50,000-year-old archaic hominin from denisova cave in southern siberia has ushered in a new age in molecular archaeology. we previously cross-compared the human, chimpanzee and neanderthal genome sequences with respect to a set of disease-causing/disease-associated missense and regulatory mutations (human gene mutation database) and succeeded in identifying genetic variants which, although apparently pathogenic in hum ...201121807602
on characterizing adaptive events unique to modern humans.ever since the first draft of the human genome was completed in 2001 there has been increased interest in identifying genetic changes that are uniquely human, which could account for our distinct morphological and cognitive capabilities with respect to other apes. recently, draft sequences of two extinct hominin genomes, a neanderthal and denisovan, have been released. these two genomes provide a much greater resolution to identify human-specific genetic differences than the chimpanzee, our clos ...201121803765
post-conflict affiliation by chimpanzees with aggressors: other-oriented versus selfish political strategy.consolation, i.e., post-conflict affiliation directed from bystanders to recent victims of aggression, has recently acquired an important role in the debate about empathy in great apes. although similar contacts have been also described for aggressors, i.e., appeasement, they have received far less attention and their function and underlying mechanisms remain largely unknown. an exceptionally large database of spontaneous conflict and post-conflict interactions in two outdoor-housed groups of ch ...201121799788
comparative anatomical analyses of the forearm muscles of cebus libidinosus (rylands et al. 2000): manipulatory behavior and tool use.the present study describes the flexor and extensor muscles in cebus libidinosus' forearm and compares them with those from humans, chimpanzees and baboons. the data is presented in quantitative anatomical indices for similarity. the capuchin forearm muscles showed important similarities with chimpanzees and humans, particularly those that act on thumb motion and allow certain degree of independence from other hand structures, even though their configuration does not enable a true opposable thum ...201121789230
aging of the cerebral cortex differs between humans and chimpanzees.several biological changes characterize normal brain aging in humans. although some of these age-associated neural alterations are also found in other species, overt volumetric decline of particular brain structures, such as the hippocampus and frontal lobe, has only been observed in humans. however, comparable data on the effects of aging on regional brain volumes have not previously been available from our closest living relatives, the chimpanzees. in this study, we used mri to measure the vol ...201121788499
quantity judgments of auditory and visual stimuli by chimpanzees (pan troglodytes).many species can choose between two visual sets of stimuli on the basis of quantity. this is true when sets are both visible, or are presented one set at a time or even one item at a time. however, we know comparatively little about how well nonhuman animals can compare auditory quantities. here, three chimpanzees (pan troglodytes) chose between two sets of food items when they only heard each item fall into different containers rather than seeing those items. this method prevented the chimpanze ...201221787100
the inversion effect reveals species differences in face processing.face recognition is a complex skill that requires the integration of facial features across the whole face, e.g., holistic processing. it is unclear whether, and to what extent, other species process faces in a manner that is similar to humans. previous studies on the inversion effect, a marker of holistic processing, in nonhuman primates have revealed mixed results in part because many studies have failed to include alternative image categories necessary to understand whether the effects are tr ...201121784381
speech perception: a language-trained chimpanzee weighs in.a language-trained chimpanzee is able to interpret synthetic 'auditory caricatures' as speech. important components of human speech perception thus rely upon general auditory mechanisms that predated the evolution of spoken language.201121783032
specific image characteristics influence attitudes about chimpanzee conservation and use as pets.chimpanzees are endangered in their native africa but in the united states, they are housed not only in zoos and research centers but owned privately as pets and performers. in 2008, survey data revealed that the public is less likely to think that chimpanzees are endangered compared to other great apes, and that this is likely the result of media misportrayals in movies, television and advertisements. here, we use an experimental survey paradigm with composite images of chimpanzees to determine ...201121779372
diversity of microsporidia (fungi: microsporidia) among captive great apes in european zoos and african sanctuaries: evidence for zoonotic transmission?abstract: two hundred and seventeen captive great apes (150 chimpanzees, pan troglodytes; 14 bonobos, pan paniscus; 53 western gorillas, gorilla gorilla) and 20 personnel from thirteen european zoos and two african sanctuaries were sampled and examined in order to determine the occurrence ofenterocytozoon bieneusi and species of encephalitozoon in faecal specimens and to compare the epidemiological situation between zoos and sanctuaries. microsporidia were detected at all sampling sites. sequenc ...201121776888
collaboration encourages equal sharing in children but not in chimpanzees.humans actively share resources with one another to a much greater degree than do other great apes, and much human sharing is governed by social norms of fairness and equity. when in receipt of a windfall of resources, human children begin showing tendencies towards equitable distribution with others at five to seven years of age. arguably, however, the primordial situation for human sharing of resources is that which follows cooperative activities such as collaborative foraging, when several in ...201121775985
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 ...201121775446
identification of novel phosphorylation modification sites in human proteins that originated after the human-chimpanzee divergence.motivation: phosphorylation modifications of specific protein residues are involved in a wide range of biological processes such as modulation of intracellular signal networks. here, we present the development and application of a bioinformatics procedure for systematic identification of human-specific phosphorylation sites in proteins that may have occurred after the human-chimpanzee divergence. results: we collected annotated human phosphorylation sites and compared each site to orthologous ma ...201121775310
increased positive selection pressure within the complementarity determining regions of the t-cell receptor ß gene in new world monkeys.because of the long-term co-evolution of tcr and mhc molecules, numerous nucleotide substitutions have accumulated within the domains of tcrß genes. we previously found that nonsynonymous nucleotide substitutions occurred more frequently in complementarity determining region (cdr)ß than in cdra, even though only a limited number of common marmoset (callithrix jacchus) and human t-cell receptor ß variable (trbv) sequences were compared. this interesting finding raised the question of whether the ...201121769905
can captive orangutans (pongo pygmaeus abelii) be coaxed into cumulative build-up of techniques?while striking cultural variation in behavior from one site to another has been described in chimpanzees and orangutans, cumulative culture might be unique to humans. captive chimpanzees were recently found to be rather conservative, sticking to the technique they had mastered, even after more effective alternatives were demonstrated. behavioral flexibility in problem solving, in the sense of acquiring new solutions after having learned another one earlier, is a vital prerequisite for cumulative ...201121767010
the limits of endowment effects in great apes (pan paniscus, pan troglodytes, gorilla gorilla, pongo pygmaeus).the endowment effect describes the bias that people often value things that they possess more than things they do not possess. thus, they are often reluctant to trade items in their possession for items of equivalent value. some nonhuman primates appear to share this bias with humans, but it remains an open question whether they show endowment effects to the same extent as humans do. we investigated endowment effects in all four great ape species (pan paniscus, pan troglodytes, gorilla gorilla, ...201121767009
polymorphism of the tryptophan hydroxylase 2 (tph2) gene is associated with chimpanzee neuroticism.in the brain, serotonin production is controlled by tryptophan hydroxylase 2 (tph2), a genotype. previous studies found that mutations on the tph2 locus in humans were associated with depression and studies of mice and studies of rhesus macaques have shown that the tph2 locus was involved with aggressive behavior. we previously reported a functional single nucleotide polymorphism (snp) in the form of an amino acid substitution, q468r, in the chimpanzee tph2 gene coding region. in the present stu ...201121765945
characteristics of expression of goose invariant chain gene and comparison of its structure among different species.the invariant chain (ii) plays a critical role in mhc class ii-associated chaperone representing antigen peptide and receptor. in this study, we cloned goose ii cdna by 5' and 3' rapid amplification of cdna ends and tested its mrna expression in the different tissues by fluorescent quantitative pcr. two ii isoforms, gii-1and gii-2, were 1,204 and 1,393 bp in length, respectively, and were found in all tested tissues. the expression of gii in all tested tissues of 2-mo-old geese was higher than i ...201121753201
chimpanzee mothers at bossou, guinea carry the mummified remains of their dead infants.the forests surrounding bossou, guinea, are home to a small, semi-isolated chimpanzee community studied for over three decades [1]. in 1992, matsuzawa [2] reported the death of a 2.5-year-old chimpanzee (jokro) at bossou from a respiratory illness. the infant's mother (jire) carried the corpse, mummified in the weeks following death, for at least 27 days. she exhibited extensive care of the body, grooming it regularly, sharing her day- and night-nests with it, and showing distress whenever they ...201021749951
pan thanatology.chimpanzees' immediate responses to the death of a group-member have rarely been described. exceptions include maternal care towards dead infants, and frenzied excitement and alarm following the sudden, traumatic deaths of older individuals [1-5]. some wild chimpanzees die in their night nest [6], but the immediate effect this has on others is totally unknown. here, with supporting video material, we describe the peaceful demise of an elderly female in the midst of her group. group responses inc ...201021749950
male-mediated gene flow in patrilocal primates.many group-living species display strong sex biases in dispersal tendencies. however, gene flow mediated by apparently philopatric sex may still occur and potentially alters population structure. in our closest living evolutionary relatives, dispersal of adult males seems to be precluded by high levels of territoriality between males of different groups in chimpanzees, and has only been observed once in bonobos. still, male-mediated gene flow might occur through rare events such as extra-group m ...201121747938
bonobos fall within the genomic variation of chimpanzees.to gain insight into the patterns of genetic variation and evolutionary relationships within and between bonobos and chimpanzees, we sequenced 150,000 base pairs of nuclear dna divided among 15 autosomal regions as well as the complete mitochondrial genomes from 20 bonobos and 58 chimpanzees. except for western chimpanzees, we found poor genetic separation of chimpanzees based on sample locality. in contrast, bonobos consistently cluster together but fall as a group within the variation of chimp ...201121747915
the evolutionary origins of friendship.convergent evidence from many species reveals the evolutionary origins of human friendship. in horses, elephants, hyenas, dolphins, monkeys, and chimpanzees, some individuals form friendships that last for years. bonds occur among females, among males, or between males and females. genetic relatedness affects friendships. in species where males disperse, friendships are more likely among females. if females disperse, friendships are more likely among males. not all friendships, however, depend o ...201021740224
gain, loss and divergence in primate zinc-finger genes: a rich resource for evolution of gene regulatory differences between species.the molecular changes underlying major phenotypic differences between humans and other primates are not well understood, but alterations in gene regulation are likely to play a major role. here we performed a thorough evolutionary analysis of the largest family of primate transcription factors, the kr++ppel-type zinc finger (kznf) gene family. we identified and curated gene and pseudogene models for kznfs in three primate species, chimpanzee, orangutan and rhesus macaque, to allow for a comparis ...201121738707
glycogen debranching enzyme 6 (agl), enolase 1 (enosf1), ectonucleotide pyrophosphatase 2 (enpp2_1), glutathione s-transferase 3 (gstm3_3) and mannosidase (man2b2) metabolism computational network analysis between chimpanzee and human left cerebrum.we identified significantly higher expression of the genes glycogen debranching enzyme 6 (agl), enolase 1 (enosf1), ectonucleotide pyrophosphatase 2 (enpp2_1), glutathione s-transferase 3 (gstm3_3) and mannosidase (man2b2) from human left cerebrums versus chimpanzees. yet the distinct low- and high-expression agl, enosf1, enpp2_1, gstm3_3 and man2b2 metabolism networks between chimpanzee and human left cerebrum remain to be elucidated. here, we constructed low- and high-expression activated and ...201121735130
zinc-finger transcription factors are associated with guanine quadruplex motifs in human, chimpanzee, mouse and rat promoters genome-wide.function of non-b dna structures are poorly understood though several bioinformatics studies predict role of the g-quadruplex dna structure in transcription. earlier, using transcriptome profiling we found evidence of widespread g-quadruplex-mediated gene regulation. herein, we asked whether potential g-quadruplex (pg4) motifs associate with transcription factors (tf). this was analyzed using 220 position weight matrices [designated as transcription factor binding sites (tfbs)], representing 187 ...201121729868
the invasion of tobacco mosaic virus rna induces endoplasmic reticulum stress-related autophagy in hela cells.the ability of human cells to defend against viruses originating from distant species has long been ignored. due to the pressure of natural evolution and human exploration, some of these viruses may be able to invade human beings. if their "fresh" host had no defenses, the viruses could cause a serious pandemic, as seen with hiv, sars and avian influenza virus, which originated from chimpanzees, the common palm civet and birds, respectively. it is unknown whether the human immune system could to ...201121729006
inferential reasoning by exclusion in children (homo sapiens).the cups task is the most widely adopted forced-choice paradigm for comparative studies of inferential reasoning by exclusion. in this task, subjects are presented with two cups, one of which has been surreptitiously baited. when the empty cup is shaken or its interior shown, it is possible to infer by exclusion that the alternative cup contains the reward. the present study extends the existing body of comparative work to include human children (homo sapiens). like chimpanzees (pan troglodytes) ...201121728410
a chimpanzee recognizes synthetic speech with significantly reduced acoustic cues to phonetic content.a long-standing debate concerns whether humans are specialized for speech perception, which some researchers argue is demonstrated by the ability to understand synthetic speech with significantly reduced acoustic cues to phonetic content. we tested a chimpanzee (pan troglodytes) that recognizes 128 spoken words, asking whether she could understand such speech. three experiments presented 48 individual words, with the animal selecting a corresponding visuographic symbol from among four alternativ ...201121723125
morphological integration of the modern human mandible during ontogeny.craniofacial integration is prevalent in anatomical modernity research. little investigation has been done on mandibular integration. integration patterns were quantified in a longitudinal modern human sample of mandibles. this integration pattern is one of modularization between the alveolar and muscle attachment regions, but with age-specific differences. the ascending ramus and nonalveolar portions of the corpus remain integrated throughout ontogeny. the alveolar region is dynamic, becoming m ...201121716741
Happy orang-utans live longer lives.Nonhuman primate ageing resembles its human counterpart. Moreover, ratings of subjective well-being traits in chimpanzees, orang-utans and rhesus macaques are similar to those of humans: they are intercorrelated, heritable, and phenotypically and genetically related to personality. We examined whether, as in humans, orang-utan subjective well-being was related to longer life. The sample included 184 zoo-housed orang-utans followed up for approximately 7 years. Age, sex, species and number of tra ...201121715398
living archaeology: artefacts of specific nest site fidelity in wild chimpanzees.savanna chimpanzees are known to re-use areas of the landscape for sleep, and patterns of chimpanzee sleeping site re-use are proposed as a referential model for early hominin archaeological site formation. we recorded the prevalence of deformed but healed branches and remnants of dead branches found around fresh nests at the savanna site of issa in ugalla, tanzania. these old nest scars were found in 79% of 112 beds. we also randomly selected potential nesting locations for a subset of 32 beds ...201121714986
beta amyloid deposition and neurofibrillary tangles spontaneously occur in the brains of captive cheetahs (acinonyx jubatus).alzheimer disease is a dementing disorder characterized pathologically by a+¦ deposition, neurofibrillary tangles, and neuronal loss. although aged animals of many species spontaneously develop a+¦ deposits, only 2 species (chimpanzee and wolverine) have been reported to develop a+¦ deposits and neurofibrillary tangles in the same individual. here, the authors demonstrate the spontaneous occurrence of a+¦ deposits and neurofibrillary tangles in captive cheetahs (acinonyx jubatus). among 22 cheet ...201121712514
animal research in the journal of applied behavior analysis.this review summarizes the 6 studies with nonhuman animal subjects that have appeared in the journal of applied behavior analysis and offers suggestions for future research in this area. two of the reviewed articles described translational research in which pigeons were used to illustrate and examine behavioral phenomena of applied significance (say-do correspondence and fluency), 3 described interventions that changed animals' behavior (self-injury by a baboon, feces throwing and spitting by a ...201121709802
deep trophoblast invasion and spiral artery remodelling in the placental bed of the lowland gorilla.in contrast to baboon or rhesus macaque, trophoblast invasion in the human placental bed occurs by the interstitial as well as the endovascular route and reaches as deep as the inner myometrium. we here describe two rare specimens of gorilla placenta. in the light of recent findings in the chimpanzee, we postulated the occurrence of deep invasion in gorilla pregnancy. tissues were processed for histology (pas, orcein), lectin staining (ulex europaeus agglutinin 1) and immunohistochemistry (cytok ...201121705078
Delayed induction, not impaired recruitment, of specific CD8(+) T cells causes the late onset of acute hepatitis C.Hepatitis C virus (HCV) infection is characterized by lack of immune-mediated liver injury despite a high level of HCV replication during the incubation phase, which lasts about 8 weeks. We investigated whether this results from delayed recruitment of HCV-specific T cells and whether it facilitates HCV persistence.201121699897
grooming network cohesion and the role of individuals in a captive chimpanzee group.social network analysis offers new tools to study the social structure of primate groups. we used social network analysis to investigate the cohesiveness of a grooming network in a captive chimpanzee group (n = 17) and the role that individuals may play in it. using data from a year-long observation, we constructed an unweighted social network of preferred grooming interactions by retaining only those dyads that groomed above the group mean. this choice of criterion was validated by the finding ...201121698658
space to choose: network analysis of social preferences in a captive chimpanzee community, and implications for management.social network analysis (sna) is rapidly gaining popularity in primatology, but its application to the management of zoo-housed primates has been largely overlooked. here i use sna techniques to explore the social structure of chimpanzees (pan troglodytes) housed in the new "budongo trail" exhibit at edinburgh zoo, uk. given that individuals have extensive space (2332 m(2)), and access to several interconnected exhibit sections, i test the hypothesis that individuals are able to choose to intera ...201121698657
signs of mood and anxiety disorders in chimpanzees.in humans, traumatic experiences are sometimes followed by psychiatric disorders. in chimpanzees, studies have demonstrated an association between traumatic events and the emergence of behavioral disturbances resembling posttraumatic stress disorder (ptsd) and depression. we addressed the following central question: do chimpanzees develop posttraumatic symptoms, in the form of abnormal behaviors, which cluster into syndromes similar to those described in human mood and anxiety disorders?201121698223
how abnormal is the behaviour of captive, zoo-living chimpanzees?many captive chimpanzees (pan troglodytes) show a variety of serious behavioural abnormalities, some of which have been considered as possible signs of compromised mental health. the provision of environmental enrichments aimed at reducing the performance of abnormal behaviours is increasing the norm, with the housing of individuals in (semi-)natural social groups thought to be the most successful of these. only a few quantitative studies of abnormal behaviour have been conducted, however, parti ...201121698219
sickness and healing and the evolutionary foundations of mind and minding.disease represents a principal tentacle of natural selection and a staple theme of evolutionary medicine. however, it is through a small portal of entry and a very long lineage that disease as sickness entered behavioural spaces and human consciousness. this has a long evolutionary history. anyone interested in the origins of medicine and psychiatry as social institution has to start with analysis of how mind and body were conceptualised and played out behaviourally following the pongid/hominin ...201121694968
acute hepatitis a virus infection is associated with a limited type i interferon response and persistence of intrahepatic viral rna.hepatitis a virus (hav) is an hepatotropic human picornavirus that is associated only with acute infection. its pathogenesis is not well understood because there are few studies in animal models using modern methodologies. we characterized hav infections in three chimpanzees, quantifying viral rna by quantitative rt-pcr and examining critical aspects of the innate immune response including intrahepatic ifn-stimulated gene expression. we compared these infection profiles with similar studies of c ...201121690403
evolutionary foundations of human prosocial sentiments.a growing body of evidence shows that humans are remarkably altruistic primates. food sharing and division of labor play an important role in all human societies, and cooperation extends beyond the bounds of close kinship and networks of reciprocating partners. in humans, altruism is motivated at least in part by empathy and concern for the welfare of others. although altruistic behavior is well-documented in other primates, the range of altruistic behaviors in other primate species, including t ...201121690372
soft-tissue anatomy of the primates: phylogenetic analyses based on the muscles of the head, neck, pectoral region and upper limb, with notes on the evolution of these muscles.apart from molecular data, nearly all the evidence used to study primate relationships comes from hard tissues. here, we provide details of the first parsimony and bayesian cladistic analyses of the order primates based exclusively on muscle data. the most parsimonious tree obtained from the cladistic analysis of 166 characters taken from the head, neck, pectoral and upper limb musculature is fully congruent with the most recent evolutionary molecular tree of primates. that is, this tree recover ...201121689100
characterization, expression profile, polymorphism and association of porcine nat9 gene.the n-acetyltransferase 9 (nat9) is an important reproduction related gene. in this study, we cloned the full-length cdna sequence of porcine nat9 gene through the rapid amplification of cdna ends method. the porcine nat9 gene encodes a protein of 206 amino acids which shares high homology with the nat9 of seven species: rhesus monkey (87%), chimpanzee (87%), human (87%), horse (86%), rat (80%), mouse (79%) and gray short-tailed opossum (79%). this gene is structured in six exons and five intron ...201121688147
comparing the performances of apes (gorilla gorilla, pan troglodytes, pongo pygmaeus) and human children (homo sapiens) in the floating peanut task.recently, mendes et al. [1] described the use of a liquid tool (water) in captive orangutans. here, we tested chimpanzees and gorillas for the first time with the same "floating peanut task." none of the subjects solved the task. in order to better understand the cognitive demands of the task, we further tested other populations of chimpanzees and orangutans with the variation of the peanut initially floating or not. twenty percent of the chimpanzees but none of the orangutans were successful. a ...201121687710
gorilla genome structural variation reveals evolutionary parallelisms with chimpanzee.structural variation has played an important role in the evolutionary restructuring of human and great ape genomes. recent analyses have suggested that the genomes of chimpanzee and human have been particularly enriched for this form of genetic variation. here, we set out to assess the extent of structural variation in the gorilla lineage by generating 10-fold genomic sequence coverage from a western lowland gorilla and integrating these data into a physical and cytogenetic framework of structur ...201121685127
human and great ape red blood cells differ in plasmalogen levels and composition.plasmalogens are ether phospholipids required for normal mammalian developmental, physiological, and cognitive functions. they have been proposed to act as membrane antioxidants and reservoirs of polyunsaturated fatty acids as well as influence intracellular signaling and membrane dynamics. plasmalogens are particularly enriched in cells and tissues of the human nervous, immune, and cardiovascular systems. humans with severely reduced plasmalogen levels have reduced life spans, abnormal neurolog ...201121679470
animal rights: chimpanzee research on trial. 201121677722
both innate and adaptive immunity mediate protective immunity against hepatitis c virus infection in chimpanzees.understanding the immunological correlates associated with protective immunity following hepatitis c virus (hcv) reexposure is a prerequisite for the design of effective hcv vaccines and immunotherapeutics. in this study we performed a comprehensive analysis of innate and adaptive immunity following hcv reexposure of two chimpanzees that had previously recovered from hcv-jfh1 infection. one of the chimpanzees, ch10274, became protected from active viremia by repeated challenges with homologous h ...201121674561
recombination rate variation in closely related species.despite their importance to successful meiosis and various evolutionary processes, meiotic recombination rates sometimes vary within species or between closely related species. for example, humans and chimpanzees share virtually no recombination hotspot locations in the surveyed portion of the genomes. however, conservation of recombination rates between closely related species has also been documented, raising an apparent contradiction. here, we evaluate how and why conflicting patterns of reco ...201121673743
lmtk3 expression in breast cancer: association with tumor phenotype and clinical outcome.interactions between kinases and the estrogen receptor ╬▒ (er╬▒) are thought to be a critical signaling pathway in the majority of human breast cancers. we have recently identified a previously uncharacterized molecule, lemur tyrosine kinase-3 (lmtk3) as a prognostic and predictive oncogenic er╬▒ regulator with a central role in endocrine resistance. unusually this protein has undergone darwinian positive selection between chimpanzees and humans suggesting it may contribute to human susceptibili ...201121671015
evolution of the cyp2d gene cluster in humans and four non-human primates.the human cytochrome p450 2d6 (cyp2d6) is a primary enzyme involved in the metabolism of about 25% of commonly used therapeutic drugs. cyp2d6 belongs to the cyp2d subfamily, a gene cluster located on chromosome 22, which comprises the cyp2d6 gene and pseudogenes cyp2d7p and cyp2d8p. although the chemical and physiological properties of cyp2d6 have been extensively studied, there has been no study to date on molecular evolution of the cyp2d subfamily in the human genome. such knowledge could grea ...201121670550
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