Publications

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
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
simian t cell leukaemia virus type i subtype b in a wild-caught gorilla (gorilla gorilla gorilla) and chimpanzee (pan troglodytes vellerosus) from cameroon.	a serological survey for human t cell leukaemia virus (htlv)/simian t cell leukaemia virus (stlv) antibodies was performed in 61 wild-caught african apes, including five gorillas and 56 chimpanzees originating from south cameroon. two young animals, a gorilla (gorilla gorilla gorilla) and a chimpanzee (pan troglodytes vellerosus), exhibited a pattern of complete htlv-i seroreactivity. sequence comparison and phylogenetic analyses using the complete ltr (750 bp) and a 522 bp fragment of the env g ...	2004	14718616
nigerian chimpanzees (pan troglodytes vellerosus) at gashaka: two years of habituation efforts.	cross-population comparisons of chimpanzees can shed light on the pathways of hominid evolution. so far, no eco-ethological data exist for the recently recognized subspecies pan troglodytes vellerosus. we report on the first 2 years of a new long-term study from what is perhaps their last remaining stronghold: the gashaka gumti national park, nigeria. the mosaic habitat (woodland, lowland and gallery forest) receives 1,826 mm rain/year, with 4-5 months being completely dry. primates at gashaka a ...	2004	15486442
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
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
leaf-swallowing in nigerian chimpanzees: evidence for assumed self-medication.	a field study in gashaka, nigeria, adds the fourth subspecies of chimpanzee, pan troglodytes vellerosus, to the list of african ape populations in which leaf-swallowing occurs. unchewed herbaceous leaves of desmodium gangeticum (leguminosae-papilionoideae) were recovered in 4% of 299 faecal samples of wild chimpanzees and clumps of sharp-edged grass leaves in 2%. the ingestion is believed to serve self-medicatory purposes because the leaves had a rough surface or were sharp-edged (which could be ...	2007	16897194
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
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
the type locality of pan troglodytes vellerosus (gray, 1862), and implications for the nomenclature of west african chimpanzees.	we show that, in 1862, richard burton collected the type specimen of pan troglodytes vellerosus not on mount cameroon, as has been generally assumed, but in gabon. therefore, p. t. vellerosus is not the correct name for the chimpanzee population of western cameroon and southern nigeria, if that population is taxonomically distinct. as first reviser, we choose the name pan troglodytes ellioti for this population of chimpanzees, based on anthropopithecus ellioti named by matschie [matschie p (1914 ...	2009	19034382
status of diurnal primate populations at the former settlement of a displaced village in cameroon.	to understand whether or not primate populations recover in areas of abandoned human settlements, data are required that allow for site-specific comparison over time. here, we present baseline information on the presence/absence and relative abundance of primate species at the abandoned settlement of the ekundukundu village, relocated out of the korup national park in 2000. between july 2007 and march 2008, 62 km of transects was surveyed for sightings and calls of primates. all eight species of ...	2010	20198684
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