genetic organization of a chimpanzee lentivirus related to hiv-1. | simian immunodeficiency viruses have been isolated from four species of monkey, the 'captive' macaque and mangabey and the 'feral' african green monkey and mandrill. while none of these viruses is a replica of hiv-1, the macaque and mangabey viruses represent correct genetic models for hiv-2, possessing exactly the same complement of genes. recently a lentivirus has been identified in two wild chimpanzees (pan troglodytes troglodytes) in gabon, west equatorial africa, and isolated from one of th ... | 1990 | 2188136 |
comparison between the complete mitochondrial dna sequences of homo and the common chimpanzee based on nonchimeric sequences. | the complete mitochondrial dna (mtdna) molecules of homo and of the common chimpanzee were sequenced. each sequence was established from tissue of one individual and thus nonchimeric. both sequences were assembled in their entirety from natural (not pcr amplified) clones. comparison with sequences in the literature identified the chimpanzee specimen as pan troglodytes verus, the west african variety of the species. the nucleotide difference between the complete human and chimpanzee sequences is ... | 1996 | 8919866 |
technical note: chromosomal and mtdna analysis of oliver. | oliver is an african ape whose species identity has been debated in the popular media and by various scientists since the early 1970s. although decisive morphological data has never been adduced on oliver, many reports indicated that oliver was morphologically unusual for a chimpanzee, particularly in his habitual bipedal posture. in addition, his diploid chromosome number was reported to be inconsistent with either human or chimpanzee, but instead intermediate between those species. we performe ... | 1998 | 9545080 |
origin of hiv-1 in the chimpanzee pan troglodytes troglodytes. | the human aids viruses human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2) represent cross-species (zoonotic) infections. although the primate reservoir of hiv-2 has been clearly identified as the sooty mangabey (cercocebus atys), the origin of hiv-1 remains uncertain. viruses related to hiv-1 have been isolated from the common chimpanzee (pan troglodytes), but only three such sivcpz infections have been documented, one of which involved a virus so divergent that it might represent a ... | 1999 | 9989410 |
env sequences of simian immunodeficiency viruses from chimpanzees in cameroon are strongly related to those of human immunodeficiency virus group n from the same geographic area. | human immunodeficiency virus type 1 (hiv-1) group n from cameroon is phylogenetically close, in env, to the simian immunodeficiency virus (siv) cpz-gab from gabon and sivcpz-us of unknown geographic origin. we screened 29 wild-born cameroonian chimpanzees and found that three (cam3, cam4, and cam5) were positive for hiv-1 by western blotting. mitochondrial dna sequence analysis demonstrated that cam3 and cam5 belonged to pan troglodytes troglodytes and that cam4 belonged to p. t. vellerosus. gen ... | 2000 | 10590144 |
morphological variation in great ape and modern human mandibles. | adult mandibles of 317 modern humans and 91 great apes were selected that showed no pathology. adult mandibles of pan troglodytes troglodytes, pongo pygmaeus pygmaeus and gorilla gorilla gorilla and from 2 modern human populations (zulu and europeans from spitalfields) were reliably sexed. thirteen measurements were defined and included mandibular height, length and breadth in representative positions. univariate statistical techniques and multivariate (principal component analysis and discrimin ... | 1999 | 10634689 |
detection of diverse variants of human immunodeficiency virus-1 groups m, n, and o and simian immunodeficiency viruses from chimpanzees by using generic pol and env primer pairs. | human immunodeficiency virus type 1 (hiv-1) infection of humans is the result of independent cross-species transmissions of simian immunodeficiency viruses (sivcpz) from naturally infected chimpanzees (pan troglodytes troglodytes) to man. to develop a polymerase chain reaction-based assay capable of detecting members of all major phylogenetic sivcpz and hiv-1 lineages (groups m, n, and o), primer pairs in conserved pol and env regions were designed. both primer sets amplified </=10 copies of sel ... | 2000 | 10823786 |
[ecology and social organization of african tropical forest primates: aid in understanding retrovirus transmission]. | the risk of transmission of primate viruses to humans is great because of their genetic proximity. it is now clear that the hiv group of retroviruses came from primates and that the origin of hiv1 is the chimpanzee subspecies of central africa, pan troglodytes troglodytes. many african primates are natural hosts of retroviruses and details of the natural history of both hosts and viruses are essential to understand the evolution of the latter. data on the demography, ecology and behaviour of thr ... | 2000 | 11030048 |
sivcpz from a naturally infected cameroonian chimpanzee: biological and genetic comparison with hiv-1 n. | thus far, simian immunodeficiency virus from chimpanzees (sivcpz) genomes have been characterized as pan troglodytes troglodytes and show a strong relation with human immunodeficiency virus (hiv)-1 n in their env genes. we fully characterized another sivcpz from p. t. troglodytes. this chimpanzee (cam5) was, as was also the host of sivcpz-cam3, wild born in cameroon, a region where all three groups of hiv-1 (m, n and o) co-occur. in contrast to other sivcpz, sivcpz-cam5 was isolated immediately ... | 2000 | 11085579 |
a chimpanzee rhadinovirus sequence related to kaposi's sarcoma-associated herpesvirus/human herpesvirus 8: increased detection after hiv-1 infection in the absence of disease. | to look for a virus related to kaposi's sarcoma-associated herpesvirus (kshv) or human herpesvirus 8 (hhv8) in chimpanzees and to investigate phylogenetic and biological similarities to kshv. | 2000 | 11125908 |
gene flow in wild chimpanzee populations: what genetic data tell us about chimpanzee movement over space and time. | the isolation of phylogenetically distinct primate immunodeficiency viruses from at least seven wild-born, captive chimpanzees indicates that viruses closely related to hiv-1 may be endemic in some wild chimpanzee populations. the search for the chimpanzee population or populations harbouring these viruses is therefore on. this paper attempts to answer the question of whether or not such populations of chimpanzees are likely to exist at all, and, if so, where they are likely to be found. we summ ... | 2001 | 11405936 |
a novel gamma 2-herpesvirus of the rhadinovirus 2 lineage in chimpanzees. | old world monkeys and, recently, african great apes have been shown, by serology and polymerase chain reaction (pcr), to harbor different gamma2-herpesviruses closely related to kaposi's sarcoma-associated herpesvirus (kshv). although the presence of two distinct lineages of kshv-like rhadinoviruses, rv1 and rv2, has been revealed in old world primates (including african green monkeys, macaques, and, recently, mandrills), viruses belonging to the rv2 genogroup have not yet been identified from g ... | 2001 | 11544194 |
paired chimpanzee hepatitis b virus (chhbv) and mtdna sequences suggest different chhbv genetic variants are found in geographically distinct chimpanzee subspecies. | the surface antigen gene region from five chronic hepatitis b virus (hbv) infected chimpanzees was amplified by pcr and the sequence determined. sequence comparison confirmed that all of the sequences were chimpanzee hepatitis b virus (chhbv) and they appeared to represent three distinct clusters or branches. to address the question of whether the three branches represented recently identified subspecies of chimpanzees, we determined the sequence of the mitochondrial dna hypervariable d loop fro ... | 2001 | 11551650 |
novel hepatitis b virus strain from a chimpanzee of central africa (pan troglodytes troglodytes) with an unusual antigenicity of the core protein. | we and others have previously reported a hepatitis b virus (hbv)-like hepadnavirus strain which seemed to be indigenous to west african chimpanzees (pan troglodytes verus). after that, we obtained an hbsag-positive serum sample from a chimpanzee from central africa, named bassi, belonging to another subspecies (p. troglodytes troglodytes). the full-genome nucleotide sequence of the hepadnavirus from bassi showed a significant difference (9-26%) from those so far reported from primates including ... | 2001 | 11684895 |
transferability of hiv by arthropods supports the hypothesis about transmission of the virus from apes to man. | the primate pan troglodytes troglodytes, a chimpanzee subspecies, has recently been defined as a natural animal host of the human immunodeficiency virus (hiv). apes are traditionally hunted in africa and are offered for sale in open-air meat markets. the bloody carcasses are regularly covered with blood-feeding flies, amongst them possibly the stable fly (stomoxvs calcitrans l.). a cosmopolitically occurring biting fly. this fly is the effective vector for the retrovirus causing equine infectiou ... | 2002 | 12061404 |
lack of evidence for hiv type 1-related sivcpz infection in captive and wild chimpanzees (pan troglodytes verus) in west africa. | serum from 387 chimpanzees (pan troglodytes verus), caught in the wild or bred in captivity, was tested for antibody to hiv-1 and hiv-2, using second- and third-generation enzyme immunoassays. six samples were repeatedly positive; however, only one of these was western blot positive. serial sera drawn before and after the western blot-positive samples were seronegative, and thus we conclude that this sample represented specimen contamination, or mislabeling. thus, none of the 387 pan troglodytes ... | 2002 | 12079561 |
aids: the agony of africa. part iv: there are two aids epidemics -- and more may be coming. the virus, past and future. | this article focuses on the origin and evolution of the aids virus. it is noted that strong evidence supports the theory that hiv originated from chimpanzees. researcher beatrice hahn, who appears to have identified the exact chimpanzee subspecies, pan troglodytes troglodytes, which harbors the mother virus of hiv, confirmed the theory. however, the way this critically important science has been reported has undermined its credibility in africa. hahn's findings showed that hiv could have pas ... | 1999 | 12295981 |
successful reproduction in wild-released orphan chimpanzees (pan troglodytes troglodytes). | we report a case of successful reproduction in wild-released orphan chimpanzees. using non-invasive genetic analysis, we determined the paternity of an infant born to a female chimpanzee released by help (habitat ecologique et liberté des primates) congo into the conkouati-douli national park, republic of congo. the sire was a released male, thus demonstrating successful reproduction in both male and female released chimpanzees. these results provide evidence that release into the wild may be a ... | 2003 | 12548336 |
occlusal relief changes with molar wear in pan troglodytes troglodytes and gorilla gorilla gorilla. | most research on primate tooth form-function relationships has focused on unworn teeth. this study presents a morphological comparison of variably worn lower second molars (m(2)s) of lowland gorillas (gorilla gorilla gorilla; n=47) and common chimpanzees (pan troglodytes troglodytes; n=54) using dental topographic analysis. high-resolution replicas of occlusal surfaces were prepared and scanned in 3d by laser scanning. the resulting elevation data were used to create a geographic information sys ... | 2003 | 12784284 |
foci of endemic simian immunodeficiency virus infection in wild-living eastern chimpanzees (pan troglodytes schweinfurthii). | simian immunodeficiency virus of chimpanzees (sivcpz) is the immediate precursor to human immunodeficiency virus type 1 (hiv-1), yet remarkably, the distribution and prevalence of sivcpz in wild ape populations are unknown. studies of sivcpz infection rates in wild chimpanzees are complicated by the species' endangered status and by its geographic location in remote areas of sub-saharan africa. we have developed sensitive and specific urine and fecal tests for sivcpz antibody and virion rna (vrn ... | 2003 | 12805455 |
analysis of the evolutionary relationships of hiv-1 and sivcpz sequences using bayesian inference: implications for the origin of hiv-1. | the most plausible origin of hiv-1 group m is an siv lineage currently represented by sivcpz isolated from the chimpanzee subspecies pan troglodytes troglodytes. the origin of hiv-1 group o is less clear. putative recombination between any of the hiv-1 and sivcpz sequences was tested using bootscanning and bayesian-scanning plots, as well as a new method using a bayesian multiple change-point (bmcp) model to infer parental sequences and crossing-over points. we found that in the case of highly d ... | 2003 | 12949143 |
survey of gorillas (gorilla gorilla gorilla) and chimpanzees (pan troglodytes troglodytes) in southwestern cameroon. | a study on the distribution and population density of the western lowland gorilla (gorilla g. gorilla) and the central chimpanzee (pan t. troglodytes) was undertaken between december 1997 and august 2000 in the campo and ma'an forests in southwestern cameroon. the aim of this survey was to estimate the densities of the apes in different parts of the area, to assess the importance of the region for the conservation of these endangered species and to determine the influence of human activities suc ... | 2004 | 14586801 |
evidence for a complex demographic history of chimpanzees. | to characterize patterns of genomic variation in central chimpanzees (pan troglodytes troglodytes) and gain insight into their evolution, we sequenced nine unlinked, intergenic regions, representing a total of 19,000 base pairs, in 14 individuals. when these dna sequences are compared with homologous sequences previously collected in humans and in western chimpanzees (pan troglodytes verus), nucleotide diversity is higher in central chimpanzees than in western chimpanzees or in humans. consisten ... | 2004 | 14963091 |
dental topography and diets of australopithecus afarensis and early homo. | diet is key to understanding the paleoecology of early hominins. we know little about the diets of these fossil taxa, however, in part because of a limited fossil record, and in part because of limitations in methods available to infer their feeding adaptations. this paper applies a new method, dental topographic analysis, to the inference of diet from fossil hominin teeth. this approach uses laser scanning to generate digital 3d models of teeth and geographic information systems software to mea ... | 2004 | 15120268 |
phylogenetic characteristics of three new hiv-1 n strains and implications for the origin of group n. | the three divergent hiv-1 groups m, n and o were very probably introduced into the human population by independent cross-species transmissions of sivcpz from the chimpanzee subspecies pan troglodytes troglodytes in central africa. | 2004 | 15199313 |
simian immunodeficiency virus infection in wild-caught chimpanzees from cameroon. | simian immunodeficiency viruses (sivcpz) infecting chimpanzees (pan troglodytes) in west central africa are the closest relatives to all major variants of human immunodeficiency virus type 1 ([hiv-1]; groups m, n and o), and have thus been implicated as the source of the human infections; however, information concerning the prevalence, geographic distribution, and subspecies association of sivcpz still remains limited. in this study, we tested 71 wild-caught chimpanzees from cameroon for evidenc ... | 2005 | 15613358 |
complete genome analysis of one of the earliest sivcpzptt strains from gabon (sivcpzgab2). | chimpanzees in west central africa (pan troglodytes troglodytes) are known to harbor simian immunodeficiency viruses (sivcpzptt) that represent the closest relatives of human immunodeficiency virus type 1 (hiv-1); however, the number of sivcpzptt strains that have been fully characterized is still limited. here, we report the complete nucleotide sequence of sivcpzgab2, a virus originally identified in 1989 in a chimpanzee (p. t. troglodytes) from gabon. analysis of this sequence reveals that siv ... | 2004 | 15650433 |
chimpanzee (pan troglodytes troglodytes) tool use in the ngotto forest, central african republic. | over a 7-month period, stick tools constructed by chimpanzees were collected and measured at the ngotto forest site in central african republic. the chimpanzees were found to use tools to dip for ants and to probe for honey. the basic descriptions of these tools and the contexts in which they were found are presented. the lengths of two of the tool types were compared with the use of a t-test for independent groups. it was found that the lengths of the tools differed significantly depending upon ... | 2005 | 15772994 |
re-analysis of a human hepatitis b virus (hbv) isolate from an east african wild born pan troglodytes schweinfurthii: evidence for interspecies recombination between hbv infecting chimpanzee and human. | according to current estimates, hepatitis b virus (hbv) has infected 2 billion people worldwide and among them, 360 million suffer from chronic hbv infection. except humans, hbv or hbv-like viruses have also been isolated from different species of apes and mammals. although recombination has been described to occur extensively between different genotypes within the human hbv lineage, no recombination event has ever been reported between human and non-human primate hbv sequences. it was our objec ... | 2005 | 15777724 |
the formation of the brush-sticks: modification of chimpanzees or the by-product of folding? | based on field research and experimental treatments of trees, we investigated the formation of the brush-like shape of digging sticks used by chimpanzees (pan troglodytes troglodytes). evidence obtained in the field consisted of digging sticks found in mboete, equatorial guinea, which is a newly reported locality for this type of tool, and campo, cameroon. digging sticks used by chimpanzees in these areas had a brush-like shape at one end, which was quite different from the other end that was pr ... | 2005 | 15883649 |
the epidemiology of simian immunodeficiency virus infection in a large number of wild- and captive-born chimpanzees: evidence for a recent introduction following chimpanzee divergence. | simian immunodeficiency virus (sivcpz) from the chimpanzee subspecies pan troglodytes troglodytes has been linked phylogenetically to the origin of hiv-1. related but distinct sivcpz strains have also been found in p. t. schweinfurthii , suggesting that sivcpz may have coevolved among the four chimpanzee subspecies. however, sivcpz strains from p. t. verus and p. t. vellerosus have not yet been identified. to better understand the epidemiology and natural history of sivcpz among chimpanzees, we ... | 2005 | 15929695 |
identification of hepatitis b virus genome in faecal sample from wild living chimpanzee (pan troglodytes troglodytes) in gabon. | non-invasive faecal sampling in the equatorial forest in gabon allowed the first identification of the hepatitis b virus (hbv-ch(rc170)) genome in samples collected from wild chimpanzees (pan troglodytes troglodytes). the hbv-ch(rcl70)sequence clustered with 100% bootstrap support with previous viral sequences obtained from pan troglodytes subspecies. this is the first evidence of hbv infection in wild apes and confirms that the hbv-like strains thus far characterized in captive apes are directl ... | 2005 | 16461230 |
detection and molecular characterization of foamy viruses in central african chimpanzees of the pan troglodytes troglodytes and pan troglodytes vellerosus subspecies. | foamy viruses are exogenous retroviruses that are highly endemic in non-human primates (nhps). recent studies, mainly performed in north america, indicated frequent simian foamy virus (sfv) infection in persons occupationally exposed to nhps. this zoonotic infection was demonstrated mainly after bites by chimpanzees [pan troglodytes (p. t.)] of the west african p. t. verus subspecies in primatology centers or zoos in the usa. | 2006 | 16556292 |
chimpanzee reservoirs of pandemic and nonpandemic hiv-1. | human immunodeficiency virus type 1 (hiv-1), the cause of human acquired immunodeficiency syndrome (aids), is a zoonotic infection of staggering proportions and social impact. yet uncertainty persists regarding its natural reservoir. the virus most closely related to hiv-1 is a simian immunodeficiency virus (siv) thus far identified only in captive members of the chimpanzee subspecies pan troglodytes troglodytes. here we report the detection of sivcpz antibodies and nucleic acids in fecal sample ... | 2006 | 16728595 |
transmission of simian immunodeficiency virus sivcpz and the evolution of infection in the presence and absence of concurrent human immunodeficiency virus type 1 infection in chimpanzees. | current data suggest that the human immunodeficiency virus type 1 (hiv-1) epidemic arose by transmission of simian immunodeficiency virus (siv) sivcpz from a subspecies of common chimpanzees (pan troglodytes troglodytes) to humans. sivcpz of chimpanzees is itself a molecular chimera of sivs from two or more different monkey species, suggesting that recombination was made possible by coinfection of one individual animal with different lentiviruses. however, very little is known about sivcpz trans ... | 2006 | 16809326 |
anthrax in western and central african great apes. | during the period of december 2004 to january 2005, bacillus anthracis killed three wild chimpanzees (pan troglodytes troglodytes) and one gorilla (gorilla gorilla gorilla) in a tropical forest in cameroon. while this is the second anthrax outbreak in wild chimpanzees, this is the first case of anthrax in gorillas ever reported. the number of great apes in central africa is dramatically declining and the populations are seriously threatened by diseases, mainly ebola. nevertheless, a considerable ... | 2006 | 16900500 |
human immunodeficiency viruses: siv infection in wild gorillas. | chimpanzees (pan troglodytes troglodytes) from west central africa are recognized as the reservoir of simian immunodeficiency viruses (sivcpzptt) that have crossed at least twice to humans: this resulted in the aids pandemic (from human immunodeficiency virus hiv-1 group m) in one instance and infection of just a few individuals in cameroon (by hiv-1 group n) in another. a third hiv-1 lineage (group o) from west central africa also falls within the sivcpzptt radiation, but the primate reservoir ... | 2006 | 17093443 |
use of a tool-set by pan troglodytes troglodytes to obtain termites (macrotermes) in the periphery of the dja biosphere reserve, southeast cameroon. | at the northern periphery of the dja biosphere reserve (southeastern cameroon) we recorded a new use of a tool-set by pan troglodytes troglodytes to prey on macrotermes muelleri, m. renouxi, m. lilljeborgi, and m. nobilis. we recovered 79 puncturing sticks and 47 fishing probes at 17 termite nests between 2002 and 2005. the mean length of the puncturing sticks (n = 77) and fishing probes (n = 45) was 52 cm and 56 cm, respectively, and the mean diameter was 9 mm and 4.5 mm, respectively. sixty-ei ... | 2006 | 17096418 |
chimpanzee tool technology in the goualougo triangle, republic of congo. | with the exception of humans, chimpanzees show the most diverse and complex tool-using repertoires of all extant species. specific tool repertoires differ between wild chimpanzee populations, but no apparent genetic or environmental factors have emerged as definitive forces shaping variation between populations. however, identification of such patterns has likely been hindered by a lack of information from chimpanzee taxa residing in central africa. we report our observations of the technologica ... | 2007 | 17194468 |
adaptation of hiv-1 to its human host. | human immunodeficiency virus type 1 (hiv-1) originated from three independent cross-species transmissions of simian immunodeficiency virus (sivcpzptt) infecting chimpanzees (pan troglodytes troglodytes) in west central africa, giving rise to pandemic (group m) and non-pandemic (groups n and o) clades of hiv-1. to identify host-specific adaptations in hiv-1 we compared the inferred ancestral sequences of hiv-1 groups m, n and o to 12 full length genome sequences of sivcpzptt and four of the outly ... | 2007 | 17545188 |
combination therapy reduces self-injurious behavior in a chimpanzee (pan troglodytes troglodytes): a case report. | self-injurious behavior (sib) remains a severe and intractable abnormal behavior for nonhuman primates in diverse settings and is a significant concern for veterinarians and behavioral scientists. to date, no single pharmacological, behavioral, social, or environmental intervention method has emerged as a reliable permanent cure for treating sib in all, or even most, individuals. implementation and evaluation of a combination therapeutic approach to treating sib for nonhuman primates is rare. in ... | 2007 | 17559320 |
the origins of hiv and implications for the global epidemic. | hiv type 1 (hiv-1) and type 2 (hiv-2) are the result of several cross-species transmissions from primates to humans. recently, the ancestral strains of hiv-1 groups m and n were shown to still persist in today's wild chimpanzee populations (pan troglodytes troglodytes) in south cameroon. lately, hiv-1 group o-related viruses have been identified in western gorillas (gorilla gorilla), called sivgor, but chimpanzees are most likely the original reservoir of this simian immunodeficiency virus (siv) ... | 2007 | 17618555 |
genetic diversity and phylogeographic clustering of sivcpzptt in wild chimpanzees in cameroon. | it is now well established that the clade of simian immunodeficiency viruses (sivs) infecting west central african chimpanzees (pan troglodytes troglodytes) and western gorillas (gorilla gorilla gorilla) comprises the progenitors of human immunodeficiency virus type 1 (hiv-1). in this study, we have greatly expanded our previous molecular epidemiological survey of sivcpz in wild chimpanzees in cameroon. the new results confirm a wide but uneven distribution of sivcpzptt in p. t. troglodytes thro ... | 2007 | 17651775 |
prevalence and genetic diversity of simian immunodeficiency virus infection in wild-living red colobus monkeys (piliocolobus badius badius) from the taï forest, côte d'ivoire sivwrc in wild-living western red colobus monkeys. | numerous african primates are infected with simian immunodeficiency viruses (sivs). it is now well established that the clade of sivs infecting west-central african chimpanzees (pan troglodytes troglodytes) and western gorillas (gorilla gorilla gorilla) represent the progenitors of human immunodeficiency virus type 1 (hiv-1), whereas hiv-2 results from different cross-species transmissions of sivsmm from sooty mangabeys (cercocebus atys atys). we present here the first molecular epidemiological ... | 2008 | 17916449 |
[genetic diversity and phylogeographic distribution of siv: how to understand the origin of hiv]. | emergence of human immunodeficiency viruses hiv-1 and hiv-2 results from interspecies transmission from simian viruses siv. sivcpzptt infecting chimpanzees, and from which the hiv-1 (subgroups m and n) is derived is still found in the pan troglodytes troglodytes population of south cameroon chimpanzees. the ancestor of hiv-1 group o, is found in the gorilla residing in western africa, but chimpanzees are in fact the initial reservoir of the siv viruses sivgor, and it is still unclear whether the ... | 2008 | 18601880 |
building an inner sanctuary: complex ptsd in chimpanzees. | through the analysis of case studies of chimpanzees (pan troglodytes troglodytes) in residence at a sanctuary, who previously sustained prolonged captivity and biomedical experimentation, we illustrate how human psychological models of diagnosis and treatment might be approached in great apes. this study reflects growing attention to ethical, scientific, and practical problems associated with psychological well-being of animals. the analysis concludes that a diagnosis of complex ptsd in chimpanz ... | 2008 | 19042307 |
origin and biology of simian immunodeficiency virus in wild-living western gorillas. | western lowland gorillas (gorilla gorilla gorilla) are infected with a simian immunodeficiency virus (sivgor) that is closely related to chimpanzee and human immunodeficiency viruses (sivcpz and hiv-1, respectively) in west central africa. although existing data suggest a chimpanzee origin for sivgor, a paucity of available sequences has precluded definitive conclusions. here, we report the molecular characterization of one partial (bq664) and three full-length (cp684, cp2135, and cp2139) sivgor ... | 2009 | 19073717 |
patterns of diversity in hiv-related loci among subspecies of chimpanzee: concordance at ccr5 and differences at cxcr4 and cx3cr1. | human immunodeficiency virus type 1 (hiv-1) arose in humans via zoonotic transmissions of simian immunodeficiency viruses (siv(cpz)) from common chimpanzees, pan troglodytes. despite the close relatedness of the two viruses and their hosts, we do not yet understand what causes siv(cpz) to be nonpathogenic in chimpanzees, and hiv/aids to be one of the most devastating infectious diseases to have emerged in humans. there have been a number of genes identified in humans that confer disease resistan ... | 2009 | 19182224 |
estimation of african apes' body size from postcranial dimensions. | we examine how african apes' postcranial skeletal dimensions and their combinations are related to body size, as represented by trunk volume, within sex-specific samples of a total of 39 central chimpanzees (pan troglodytes troglodytes) and 34 western gorillas (gorilla gorilla gorilla). we examine this relationship by determining the strength of the correlation between selected skeletal dimensions and trunk volume. the findings indicate that sex should be taken into account when possible. most t ... | 2009 | 19221857 |
on the diversity of malaria parasites in african apes and the origin of plasmodium falciparum from bonobos. | the origin of plasmodium falciparum, the etiological agent of the most dangerous forms of human malaria, remains controversial. although investigations of homologous parasites in african apes are crucial to resolve this issue, studies have been restricted to a chimpanzee parasite related to p. falciparum, p. reichenowi, for which a single isolate was available until very recently. using pcr amplification, we detected plasmodium parasites in blood samples from 18 of 91 individuals of the genus pa ... | 2010 | 20169187 |
a survey of chimpanzees (pan troglodytes troglodytes) and gorillas (gorilla gorilla gorilla) in the selectively logged ngotto forest, central african republic. | currently, the timber company industrie forestiere du batalimo is selectively logging the ngotto forest in the central african republic. the forest is home to a population of chimpanzees (pan troglodytes troglodytes) and gorillas (gorilla gorilla gorilla) and provides the bofi-speaking people of grima with food, medicine, housing material, and other commodities. over a 7-month period, the research team conducted a line-transect survey of the great ape population in the forests to the south of gr ... | 2009 | 20183473 |
a legacy of low-impact logging does not elevate prevalence of potentially pathogenic protozoa in free-ranging gorillas and chimpanzees in the republic of congo: logging and parasitism in african apes. | many studies have examined the long-term effects of selective logging on the abundance and diversity of free-ranging primates. logging is known to reduce the abundance of some primate species through associated hunting and the loss of food trees for frugivores; however, the potential role of pathogens in such primate population declines is largely unexplored. selective logging results in a suite of alterations in host ecology and forest structure that may alter pathogen dynamics in resident wild ... | 2010 | 20238141 |
detection and characterization of hepatitis b virus strains from wild-caught gorillas and chimpanzees in cameroon, central africa. | previous epidemiological studies have reported a high prevalence of hepatitis b virus (hbv) infection in chimpanzees in gabon and congo, central africa. there is no data for this species from cameroon. to date few cases of active hbv infection have been documented in gorillas and only one complete hbv sequence has been described from a wild-caught gorilla originating from cameroon and housed in germany. since gorillas are apes found in cameroon, we thus investigated the prevalence and genetic re ... | 2010 | 20471498 |
the evolution of hiv-1 and the origin of aids. | the major cause of acquired immune deficiency syndrome (aids) is human immunodeficiency virus type 1 (hiv-1). we have been using evolutionary comparisons to trace (i) the origin(s) of hiv-1 and (ii) the origin(s) of aids. the closest relatives of hiv-1 are simian immunodeficiency viruses (sivs) infecting wild-living chimpanzees (pan troglodytes troglodytes) and gorillas (gorilla gorilla gorilla) in west central africa. phylogenetic analyses have revealed the origins of hiv-1: chimpanzees were th ... | 2010 | 20643738 |
characterization of a new simian immunodeficiency virus strain in a naturally infected pan troglodytes troglodytes chimpanzee with aids related symptoms. | data on the evolution of natural siv infection in chimpanzees (sivcpz) and on the impact of siv on local ape populations are only available for eastern african chimpanzee subspecies (pan troglodytes schweinfurthii), and no data exist for central chimpanzees (pan troglodytes troglodytes), the natural reservoir of the ancestors of hiv-1 in humans. here, we report a case of naturally-acquired sivcpz infection in a p.t.troglodytes chimpanzee with clinical and biological data and analysis of viral ev ... | 2011 | 21232091 |
assessment of gastrointestinal parasites in wild chimpanzees (pan troglodytes troglodytes) in southeast cameroon. | we tested 114 faecal samples from wild simian immunodeficiency virus (siv)-positive (n = 43) and siv-negative (n = 71) chimpanzees (pan troglodytes troglodytes) in southeast cameroon for the presence of gastrointestinal parasites by direct smear. we observed cysts from different protozoa (entamoeba coli and entamoeba histolytica / entamoeba dispar, endolimax nana, iodamoeba butschlii, chilomastix mesnili, balantidium coli and blastocystis cells) and trophozoites from troglodytella abrassarti and ... | 2014 | 24781023 |
shedding of clostridium difficile pcr ribotype 078 by zoo animals, and report of an unstable metronidazole-resistant isolate from a zebra foal (equus quagga burchellii). | clostridium difficile is an emerging and potentially zoonotic pathogen, but its prevalence in most animal species, including exhibition animals, is currently unknown. in this study we assessed the prevalence of faecal shedding of c. difficile by zoo animals, and determined the ribotype, toxin profile and antimicrobial susceptibility of recovered isolates. a total of 200 samples from 40 animal species (36.5% of which came from plains zebra, equus quagga burchellii) were analysed. c. difficile was ... | 2014 | 24467928 |
the transmembrane domain of hiv-1 vpu is sufficient to confer anti-tetherin activity to sivcpz and sivgor vpu proteins: cytoplasmic determinants of vpu function. | the acquisition of effective vpu-mediated anti-tetherin activity to promote virion release following transmission of sivcpzptt from central chimpanzees (pan troglodytes troglodytes) to humans distinguishes pandemic hiv-1 group m strains from non-pandemic group n, o and p viruses and may have been a prerequisite for their global spread. some functional motifs in the cytoplasmic region of hiv-1 m vpus proposed to be important for anti-tetherin activity are more frequently found in the vpu proteins ... | 2013 | 23514615 |
hiv-1 group o origin, evolution, pathogenesis, and treatment: unraveling the complexity of an outlier 25 years later. | twenty-five years ago, an aberrant hiv-1 (now classified as hiv-1 group o) was described from a cameroonian hiv patient living in belgium. the epicenter of group o was later found to be in central africa, overlapping with the geographical location of the central chimpanzees (pan troglodytes troglodytes) and western gorillas (gorilla gorilla), the likely original hosts of group o. although the prevalence of group o has remained low at 1-2% in cameroon, some european countries (france, spain, belg ... | 2015 | 26450803 |
beyond the cut hunter: a historical epidemiology of hiv beginnings in central africa. | in the absence of direct evidence, an imagined "cut hunter" stands in for the index patient of pandemic hiv/aids. during the early years of colonial rule, this explanation goes, a hunter was cut or injured from hunting or butchering a chimpanzee infected with simian immunodeficiency virus, resulting in the first sustained human infection with the virus that would emerge as hiv-1m. we argue here that the "cut hunter" relies on a historical misunderstanding and ecological oversimplification of hum ... | 2016 | 27718030 |
neutralization properties of simian immunodeficiency viruses infecting chimpanzees and gorillas. | broadly cross-reactive neutralizing antibodies (bnabs) represent powerful tools to combat human immunodeficiency virus type 1 (hiv-1) infection. here, we examined whether hiv-1-specific bnabs are capable of cross-neutralizing distantly related simian immunodeficiency viruses (sivs) infecting central (pan troglodytes troglodytes) (sivcpzptt) and eastern (pan troglodytes schweinfurthii) (sivcpzpts) chimpanzees (n = 11) as well as western gorillas (gorilla gorilla gorilla) (sivgor) (n = 1). we foun ... | 2015 | 25900654 |
evidence for selection at hiv host susceptibility genes in a west central african human population. | hiv-1 derives from multiple independent transfers of simian immunodeficiency virus (siv) strains from chimpanzees to human populations. we hypothesized that human populations in west central africa may have been exposed to siv prior to the pandemic, and that previous outbreaks may have selected for genetic resistance to immunodeficiency viruses. to test this hypothesis, we examined the genomes of biaka western pygmies, who historically resided in communities within the geographic range of the ce ... | 2012 | 23217182 |
new strain of simian immunodeficiency virus identified in wild-born chimpanzees from central africa. | studies of primate lentiviruses continue to provide information about the evolution of simian immunodeficiency viruses (sivs) and the origin and emergence of hiv since chimpanzees in west-central africa (pan troglodytes troglodytes) were recognized as the reservoir of sivcpzptt viruses, which have been related phylogenetically to hiv-1. using in-house peptide elisas to study siv prevalence, we tested 104 wild-born captive chimpanzees from gabon and congo. we identified two new cases of sivcpz in ... | 2012 | 22984489 |
eastern chimpanzees, but not bonobos, represent a simian immunodeficiency virus reservoir. | chimpanzees in west central africa (pan troglodytes troglodytes) are endemically infected with simian immunodeficiency viruses (sivcpzptt) that have crossed the species barrier to humans and gorillas on at least five occasions, generating pandemic and nonpandemic forms of human immunodeficiency virus type 1 (hiv-1) as well as gorilla siv (sivgor). chimpanzees in east africa (pan troglodytes schweinfurthii) are also infected with sivcpz; however, their viruses (sivcpzpts) have never been found in ... | 2012 | 22837215 |
diversity of malaria parasites in great apes in gabon. | until 2009, the laverania subgenus counted only two representatives: plasmodium falciparum and plasmodium reichenowi. the recent development of non-invasive methods allowed re-exploration of plasmodial diversity in african apes. although a large number of great ape populations have now been studied regarding plasmodium infections in africa, there are still vast areas of their distribution that remained unexplored. gabon constitutes an important part of the range of western central african great ... | 2015 | 25889049 |
why are nigeria-cameroon chimpanzees (pan troglodytes ellioti) free of sivcpz infection? | simian immunodeficiency virus (siv) naturally infects two subspecies of chimpanzee: pan troglodytes troglodytes from central africa (sivcpzptt) and p. t. schweinfurtii from east africa (sivcpzpts), but is absent in p. t. verus from west africa and appears to be absent in p. t. ellioti inhabiting nigeria and western cameroon. one explanation for this pattern is that p. t. troglodytes and p. t schweinfurthii may have acquired sivcpz after their divergence from p. t. verus and p. t. ellioti. howeve ... | 2016 | 27505066 |
strongyloides infections of humans and great apes in dzanga-sangha protected areas, central african republic and in degraded forest fragments in bulindi, uganda. | dna sequence analysis was carried out on strongyloides spp. larvae obtained from fecal samples of local humans, a wild western lowland gorilla (gorilla gorilla gorilla) and a central chimpanzee (pan troglodytes troglodytes) inhabiting dzanga-sangha protected areas (dspa), central african republic, and eastern chimpanzees (pan troglodytes schweinfurthii) living in degraded forest fragments on farmland in bulindi, uganda. from humans, both strongyloides fuelleborni and strongyloides stercoralis we ... | 2016 | 27180094 |
morbid attraction to leopard urine in toxoplasma-infected chimpanzees. | parasites are sometimes capable of inducing phenotypic changes in their hosts to improve transmission [1]. toxoplasma gondii, a protozoan that infects a broad range of warm-blooded species, is one example that supports the so-called 'parasite manipulation hypothesis': it induces modifications in rodents' olfactory preferences, converting an innate aversion for cat odor into attraction and probably favoring trophic transmission to feline species, its only definitive hosts [2]. in humans, t. gondi ... | 2016 | 26859275 |
genetic characterization of simian foamy viruses infecting humans. | simian foamy viruses (sfvs) are retroviruses that are widespread among nonhuman primates (nhps). sfvs actively replicate in their oral cavity and can be transmitted to humans after nhp bites, giving rise to a persistent infection even decades after primary infection. very few data on the genetic structure of such sfvs found in humans are available. in the framework of ongoing studies searching for sfv-infected humans in south cameroon rainforest villages, we studied 38 sfv-infected hunters whose ... | 2012 | 23015714 |
intestinal flora modification of arthritis pattern in spondyloarthropathy. | the reactive form of spondyloarthropathy appears inducible by exposure to agents of infectious diarrhea, but do those organisms represent the tip of the iceberg, as indicated by renewed interest in gastrointestinal flora? prevalence of spondyloarthropathy (20% of chimpanzees [pan] and 28% of gorillas) is independent of subspecies and species, respectively. however, there are major differences in arthritis patterns, a characteristic shared with humans. | 2015 | 26267718 |
tooth cusp sharpness as a dietary correlate in great apes. | mammalian molars have undergone heavy scrutiny to determine correlates between morphology and diet. here, the relationship between one aspect of occlusal morphology, tooth cusp radius of curvature (roc), and two broad dietary categories, folivory and frugivory, is analyzed in apes. the author hypothesizes that there is a relationship between tooth cusp roc and diet, and that folivores have sharper teeth than frugivores, and further test the correlation between tooth cusp roc and tooth cusp size. ... | 2014 | 24227163 |
chlamydia-related bacteria in free-living and captive great apes, gabon. | | 2016 | 27869611 |
how much more would knm-wt 15000 have grown? | because of its completeness, the juvenile homo ergaster/erectus knm-wt 15000 has played an important role in studies of the evolution of body form in homo. early attempts to estimate his adult body size used modern human growth models. however, more recent evidence, particularly from the dentition, suggests that he may have had a more chimpanzee-like growth trajectory. here we re-estimate his adult stature and body mass using ontogenetic data derived from four african ape taxa: pan troglodytes t ... | 2015 | 25449954 |
niche differentiation and dietary seasonality among sympatric gorillas and chimpanzees in loango national park (gabon) revealed by stable isotope analysis. | the feeding ecology of sympatric great ape species yields valuable information for palaeodietary reconstructions in sympatric early hominin species. however, no isotopic references on sympatrically living apes and their feeding ecology are currently available. here we present the first isotopic study on sympatric great apes, namely western lowland gorillas (gorilla gorilla gorilla) and central chimpanzees (pan troglodytes troglodytes) from loango national park, gabon. we successfully analyzed th ... | 2014 | 24373257 |
effective sociodemographic population assessment of elusive species in ecology and conservation management. | wildlife managers are urgently searching for improved sociodemographic population assessment methods to evaluate the effectiveness of implemented conservation activities. these need to be inexpensive, appropriate for a wide spectrum of species and straightforward to apply by local staff members with minimal training. furthermore, conservation management would benefit from single approaches which cover many aspects of population assessment beyond only density estimates, to include for instance so ... | 2013 | 24101982 |
assessment of landscape-scale distribution of sympatric great apes in african rainforests: concurrent use of nest and camera-trap surveys. | information on the distribution and abundance of sympatric great apes (pan troglodytes troglodytes and gorilla gorilla gorilla) are important for effective conservation and management. although much research has been done to improve the precision of nest-surveys, trade-offs between data-reliability and research-efficiency have not been solved. in this study, we used different approaches to assess the landscape-scale distribution patterns of great apes. we conducted a conventional nest survey and ... | 2013 | 23907925 |
significant differentiation in the apolipoprotein(a)/lipoprotein(a) trait between chimpanzees from western and central africa. | elevated lipoprotein(a) (lp(a)) plasma concentrations are a risk factor for cardiovascular disease in humans, largely controlled by the lpa gene encoding apolipoprotein(a) (apo(a)). lp(a) is composed of low-density lipoprotein (ldl) and apo(a) and restricted to catarrhini. a variable number of kringle iv (kiv) domains in lpa lead to a size polymorphism of apo(a) that is inversely correlated with lp(a) concentrations. smaller apo(a) isoforms and higher lp(a) levels in central chimpanzees (pan tro ... | 2017 | 28671714 |
proximal femoral diaphyseal cross-sectional geometry in orrorin tugenensis. | functional adaptations in femora attributed to orrorin tugenensis provide a unique opportunity to examine locomotor behavior very early in the hominin lineage. this study examines relative cortical thickness, cortical area (ca) relative to the polar moment of area (j), and j relative to femoral head superoinferior diameter (fhd) in the proximal femur of o. tugenensis (bar 1002'00 and bar 1003'00), and compares patterns in this early hominin with those in a sample of modern humans (n=31), plio-pl ... | 2012 | 22609080 |
discrimination of extant pan species and subspecies using the enamel-dentine junction morphology of lower molars. | previous research has demonstrated that species and subspecies of extant chimpanzees and bonobos can be distinguished on the basis of the shape of their molar crowns. thus, there is potential for fossil taxa, particularly fossil hominins, to be distinguished at similar taxonomic levels using molar crown morphology. unfortunately, due to occlusal attrition, the original crown morphology is often absent in fossil teeth, and this has limited the amount of shape information used to discriminate homi ... | 2009 | 19382140 |
divergence population genetics of chimpanzees. | the divergence of two subspecies of common chimpanzees (pan troglodytes troglodytes and p. t. verus) and the bonobo (p. paniscus) was studied using a recently developed method for analyzing population divergence. under the isolation with migration model, the posterior probability distributions of divergence time, migration rates, and effective population sizes were estimated for large multilocus dna sequence data sets drawn from the literature. the bonobo and the common chimpanzee are estimated ... | 2005 | 15483319 |
extraction of honey from underground bee nests by central african chimpanzees (pan troglodytes troglodytes) in loango national park, gabon: techniques and individual differences. | a detailed analysis of tool use behaviors can disclose the underlying cognitive traits of the users. we investigated the technique used by wild chimpanzees to extract the underground nests of stingless bees (meliplebeia lendliana), which represent a hard-to-reach resource given their highly undetectable location. using remote-sensor camera trap footage, we analyzed 151 visits to 50 different bee nests by 18 adult chimpanzees of both sexes. we quantified the degree of complexity and flexibility o ... | 2017 | 28464365 |
tool transfers are a form of teaching among chimpanzees. | teaching is a form of high-fidelity social learning that promotes human cumulative culture. although recently documented in several nonhuman animals, teaching is rare among primates. in this study, we show that wild chimpanzees (pan troglodytes troglodytes) in the goualougo triangle teach tool skills by providing learners with termite fishing probes. tool donors experienced significant reductions in tool use and feeding, while tool recipients significantly increased their tool use and feeding af ... | 2016 | 27725706 |
genome sequence of a central chimpanzee-associated polyomavirus related to bk and jc polyomaviruses, pan troglodytes troglodytes polyomavirus 1. | we amplified and sequenced the genome of a polyomavirus infecting a central chimpanzee (pan troglodytes troglodytes). this virus, which is closely related to bk and jc polyomaviruses, may help shed a new light on these human pathogens' evolutionary history. | 2015 | 26337874 |
the complete mitochondrial genome of the central chimpanzee, pan troglodytes troglodytes. | this study first report the complete mitochondrial genome sequence of the central chimpanzee, pan troglodytes troglodytes. the genome was a total of 16 556 bp in length and had a base composition of a (31.05%), g (12.95%), c (30.84%), and t (25.16%), indicating that the percentage of a + t (56.21%) is higher than g + c (43.79%). similar to other primates, it possessed a typically conserved structure, including 13 protein-coding genes, 22 transfer rna genes, 2 ribosomal rna genes and 1 control re ... | 2016 | 26190079 |
inference of purifying and positive selection in three subspecies of chimpanzees (pan troglodytes) from exome sequencing. | we study genome-wide nucleotide diversity in three subspecies of extant chimpanzees using exome capture. after strict filtering, single nucleotide polymorphisms and indels were called and genotyped for greater than 50% of exons at a mean coverage of 35× per individual. central chimpanzees (pan troglodytes troglodytes) are the most polymorphic (nucleotide diversity, θw = 0.0023 per site) followed by eastern (p. t. schweinfurthii) chimpanzees (θw = 0.0016) and western (p. t. verus) chimpanzees (θw ... | 2015 | 25829516 |
the sampling scheme matters: pan troglodytes troglodytes and p. t. schweinfurthii are characterized by clinal genetic variation rather than a strong subspecies break. | populations of an organism living in marked geographical or evolutionary isolation from other populations of the same species are often termed subspecies and expected to show some degree of genetic distinctiveness. the common chimpanzee (pan troglodytes) is currently described as four geographically delimited subspecies: the western (p. t. verus), the nigerian-cameroonian (p. t. ellioti), the central (p. t. troglodytes) and the eastern (p. t. schweinfurthii) chimpanzees. although these taxa woul ... | 2015 | 25330245 |
insect prey characteristics affecting regional variation in chimpanzee tool use. | it is an ongoing interdisciplinary pursuit to identify the factors shaping the emergence and maintenance of tool technology. field studies of several primate taxa have shown that tool using behaviors vary within and between populations. while similarity in tools over spatial and temporal scales may be the product of socially learned skills, it may also reflect adoption of convergent strategies that are tailored to specific prey features. much has been claimed about regional variation in chimpanz ... | 2014 | 24602365 |
ecological and social correlates of chimpanzee tool use. | the emergence of technology has been suggested to coincide with scarcity of staple resources that led to innovations in the form of tool-assisted strategies to diversify or augment typical diets. we examined seasonal patterns of several types of tool use exhibited by a chimpanzee (pan troglodytes) population residing in central africa, to determine whether their technical skills provided access to fallback resources when preferred food items were scarce. chimpanzees in the goualougo triangle exh ... | 2013 | 24101626 |
ground night nesting in chimpanzees: new insights from central chimpanzees (pan troglodytes troglodytes) in south-east cameroon. | some chimpanzee populations exhibit ground night nesting, which occurs in different habitat types, is driven by a variety of interconnected factors, and may reflect cultural or social differences. this has important implications for ape conservation management, given that accurate nest builder identification is required to estimate density, crucial in monitoring, and allows inferences about environmental and social factors that may have contributed to the transition from tree to ground sleeping ... | 2013 | 23988519 |
use of rnalater as a preservation method for parasitic coprology studies in wild-living chimpanzees. | we evaluated the use of an rna stabilisation buffer, rnalater (ambion, austin, texas), as a preservation medium for parasitic coprology analysis of faecal samples collected from chimpanzees living in the wild (pan troglodytes troglodytes). thirty faecal samples collected in the forests of south-east cameroon (mambele area) from 2003 to 2011 were preserved in rnalater at -80 °c and analysed for their parasite content. we identified and counted parasitic elements and assessed their shape, size and ... | 2013 | 23850999 |
the mammalian bony labyrinth reconsidered, introducing a comprehensive geometric morphometric approach. | the bony labyrinth in the temporal bone houses the sensory systems of balance and hearing. while the overall structure of the semicircular canals and cochlea is similar across therian mammals, their detailed morphology varies even among closely related groups. as such, the shape of the labyrinth carries valuable functional and phylogenetic information. here we introduce a new, semilandmark-based three-dimensional geometric morphometric approach to shape analysis of the labyrinth, as a major impr ... | 2012 | 22404255 |
exploring femoral diaphyseal shape variation in wild and captive chimpanzees by means of morphometric mapping: a test of wolff's law. | long bone shafts (diaphyses) serve as load-bearing structures during locomotion, implying a close relationship between diaphyseal form and its locomotor function. diaphyseal form-function relationships, however, are complex, as they are mediated by various factors such as developmental programs, evolutionary adaptation, and functional adaptation through bone remodeling during an individual's lifetime. the effects of the latter process ("wolff's law") are best assessed by comparing diaphyseal mor ... | 2011 | 21328564 |
twenty new microsatellite loci for use with hair and faecal samples in the chimpanzee (pan troglodytes troglodytes). | | 2006 | 10828699 |
feeding behaviour and diet of chimpanzees (pan troglodytes troglodytes) in the okorobikó mountains of rio muni (west africa). | some aspects of the nutritional behaviour of the okorobikó-matama (rio muni, west africa) chimpanzees have been studied over two periods--from june 1963 to september 1964 and from july 1966 to february 1969. this research totaled 640 h, 119 of which were in sustained contact with the animals. we have complied a list of 43 plant and two termite species consumed by the chimpanzees. we studied the relative importance of the plants consumed in terms of the four principal biotopes and seasonal cycles ... | 1979 | 118604 |
study of meiosis in the chimpanzee, pan troglodytes troglodytes (blumenbach 1779). | | 1972 | 4649368 |