Publications

the effects of substratum inclination on locomotor patterns in primates.	to explore the change from the horizontal quadrupedal walking to the vertical climbing in primates, i designed an experiment on an inclined substratum. the subjects were an adult male japanese macaque and a 2-year-old female white-handed gibbon. the animals moved on a substratum made of bamboo pipe (8 cm diameter). the inclination of the substratum was changed from 15 degrees to 65 degrees in 5-degree increments for the japanese macaque and from 20 degrees to 70 degrees with 10-degree increments ...	2002	12050892
structure, molecular evolution, and gene expression of primate superoxide dismutases.	mn- and cu,zn-superoxide dismutase (sod) cdnas of eight primate species, pan troglodytes, pongo pygmaeus, hylobates lar, macaca fuscata, macaca fascicularis, macaca mulatta, cebus apella, and callithrix jacchus, were cloned. the whole protein-coding sequences were covered, comparing 198 and 153 (or 154) amino acids, for mn- and cu,zn-sods, respectively. residues forming metal ligands were completely conserved in the two primate sods and nucleotide/amino acid substitutions were more frequent in c ...	2002	12383507
localized hypoplasia of the primary canine in bonobos, orangutans, and gibbons.	this paper extends observations by lukacs ([1999] am. j. phys. anthropol. 110:351-363; [2001] am. j. phys. anthropol. 116:199-208) of localized hypoplasia of the primary canine (lhpc) among large apes to gibbons, bonobos, and orangutans. lhpc is a roughly circular area of deficient enamel on the labial surface of primary canine teeth which, on current evidence from humans, forms several months after birth due to malnutrition-induced craniofacial osteopenia, leading to crypt fenestration that exp ...	2003	12489137
mechanisms of force and power production in unsteady ricochetal brachiation.	brachiators travel by swinging beneath handholds, and it is not obvious how these animals manage to accelerate and decelerate in a horizontal direction, especially when moving rapidly. most previous analyses focused on brachiation in highly constrained laboratory conditions that induced steady-state locomotion. emerging understanding of brachiation suggests that much of gibbon locomotory behavior and morphology must be considered within the context of the complexities of the natural environment: ...	2003	12627531
detailed hylobates lar karyotype defined by 25-color fish and multicolor banding.	a comprehensive and detailed comparative chromosome map of the white-handed gibbon (hylobates lar = hla) has been established by hybridizing the recently developed complete human multicolor banding (mcb) probe set on metaphase chromosomes of a male hla lymphoblastoid cell line. thus, it was possible to precisely determine the breakpoints and distribution plus orientation of specific dna-regions in this cytogenetically highly rearranged species compared to homo sapiens (hsa). in general, the obta ...	2003	12851708
effect of diet on dental development in four species of catarrhine primates.	in this study, dental development is described in two pairs of closely related catarrhine primate species that differ in their degree of folivory: 1) hylobates lar and symphalangus syndactylus, and 2) papio hamadryas hamadryas and semnopithecus entellus. growth increments in histological thin sections are used to reconstruct the chronology of dental development to determine how dental development is accelerated in the more folivorous species of each pair. although anterior tooth formation appear ...	2003	12966517
[microsporum audouini-infection in a hooded gibbon (hylobates lar)].		1962	13869524
plasmodium youngi n. sp., a malaria parasite of the malayan gibbon, hylobates lar lar.		1964	14125875
[on the isolation of an atypical strain of microsporum canis from a whitehanded gibbon (hylobates lar)].		1964	14230191
head movements during locomotion in a gibbon and japanese macaques.	kinematic analysis of head and body movements during locomotion in macaca fuscata and hylobates lar revealed that coordinated head rotation and translation that have been reported to play an important role in stabilizing gaze during locomotion for humans are also observed in non-human primates. the fact that well-coordinated head movements were observed in two species, and during both bipedal and quadrupedal walking, suggests that the head orientation during locomotion is well regulated in the m ...	2004	15094468
cross-species amplification of human microsatellite markers using noninvasive samples from white-handed gibbons (hylobates lar).	analysis of the population genetic structure and reproductive strategies of various primate species has been facilitated by cross-species amplification (i.e., the use of microsatellite markers developed in one species for analysis of another). in this study we screened 47 human-derived markers to assess their utility in the white-handed gibbon (hylobates lar). only eight produced accurate, reliable results, and exhibited levels of polymorphism that were adequate for individual identification. th ...	2004	15356855
new insights into the evolution of chromosome 1.	a complex low-repetitive human dna probe (bac rp11-35b4) together with two microdissection-derived region-specific probes of the multicolor banding (mcb) probe-set for chromosome 1 were used to re-analyze the evolution of human chromosome 1 in comparison to four ape species. bac rp11-35b4 derives from 1q21 and contains 143 kb of non-repetitive dna; however, it produces three specific fish signals in 1q21, 1p12 and 1p36.1 of homo sapiens (hsa). human chromosome 1 was studied in comparison to its ...	2005	15545733
functional analysis of the gibbon foot during terrestrial bipedal walking: plantar pressure distributions and three-dimensional ground reaction forces.	this paper gives a detailed analysis of bipedal walking in the white-handed gibbon, based on collected pressure and force data. these data were obtained from four gibbons in the wild animal park, planckendael, belgium, by using a walkway with integrated force plate and pressure mat. this is the first study that collects and describes dynamic plantar pressure data of bipedally walking gibbons, and combines these with force plate data. the combination of these data with previously described roll-o ...	2005	15861422
fatal human herpesvirus type 1 infection in a white-handed gibbon (hylobates lar).	this report documents a case of spontaneous, fatal, and likely recrudescent human herpesvirus type 1 (hhv-1) infection in a captive white-handed gibbon (hylobates lar) confirmed by polymerase chain reaction (pcr). an approximately 44-year-old, captive, female, white-handed gibbon with a history of recurrent conjunctivitis and occasional seizures became acutely weak, disoriented, and ataxic. a postictal state was suspected by caretakers and veterinary staff, and euthanasia was ultimately elected ...	2005	16130997
recurrence plot analysis of nonstationary data: the understanding of curved patterns.	recurrence plots of the calls of the nomascus concolor (western black crested gibbon) and hylobates lar (white-handed gibbon) show characteristic circular, curved, and hyperbolic patterns superimposed to the main temporal scale of the signal. it is shown that these patterns are related to particular nonstationarities in the signal. some of them can be reproduced by artificial signals like frequency modulated sinusoids and sinusoids with time divergent frequency. these modulations are too faint t ...	2005	16196612
locomotor versatility in the white-handed gibbon (hylobates lar): a spatiotemporal analysis of the bipedal, tripedal, and quadrupedal gaits.	this study gives a qualitative and quantitative description of the different terrestrial locomotor modes of a group of white-handed gibbons (hylobates lar) from the wild animal park planckendael, belgium. the gibbons were filmed during voluntary locomotion on a grassy and smooth substrate and on a pole. these video images allowed us to define seven different gait types, based on spatial and temporal footfall patterns. consequent digitization of the video images (n = 254) yielded duty factors, st ...	2006	16516949
morphological analysis of the hindlimb in apes and humans. i. muscle architecture.	we present quantitative data on the hindlimb musculature of pan paniscus, gorilla gorilla gorilla, gorilla gorilla graueri, pongo pygmaeus abelii and hylobates lar and discuss the findings in relation to the locomotor habits of each. muscle mass and fascicle length data were obtained for all major hindlimb muscles. physiological cross-sectional area (pcsa) was estimated. data were normalized assuming geometric similarity to allow for comparison of animals of different size/species. muscle mass s ...	2006	16761973
prevalence and molecular characterization of the polymerase gene of gibbon lymphocryptovirus.	lymphocryptovirus (lcv) is found in various non-human primates. as a herpesvirus naturally infecting gibbons it is closely related to human epstein-barr virus (ebv) with which it shares considerable genetic, biological and epidemiologic features.	2006	16764671
the boundary of macaque rdna is constituted by low-copy sequences conserved during evolution.	in macaca mulatta, the single rdna array is flanked by a patchwork of sequences including subregions of human yp11.2, 4q35.2, and 10p15.3. this composite dna region is characterized by unique or low-copy sequences, resembling a potentially transcribed region. the analysis of cercopithecus aethiops, presbytis cristata, and hylobates lar suggests that this complex sequence organization could be shared by old world monkey and lesser ape species. after the lesser apes/great apes divergence, the uniq ...	2006	16765020
the dynamics of hylobatid bipedalism: evidence for an energy-saving mechanism?	when gibbons travel through the forest canopy, brachiation is alternated with short bipedal bouts over horizontal boughs. we know, from previous research, that brachiation is a very efficient locomotor mode that makes use of a pendulum-like exchange of energy, but to date, nothing is known about the dynamics of hylobatid bipedalism. we wondered if gibbons also make use of an efficient gait mechanism during bipedal locomotion. to investigate this, we calculated oscillations of the centre of mass ...	2006	16857866
functional morphology of the first cervical vertebra in humans and nonhuman primates.	the cervical vertebral column bears or balances the weight of the head supported by the nuchal muscles that partly originate from the cervical vertebrae. the position of the head relative to the vertebral column, and consequently locomotion and posture behavior, could thus be associated with the form of the cervical vertebrae. in spite of this assumption and some empirical indications along these lines, primate vertebral morphologies have been reported to be very similar and not clearly related ...	2006	16955497
speed modulation in hylobatid bipedalism: a kinematic analysis.	gibbons are highly arboreal apes, and it is expected that their bipedal locomotion will show some particularities related to the arboreal environment. previous research has shown that, during hylobatid bipedalism, unsupported phases are rare and stride frequencies are relatively low. this study confirms previous findings, and we suggest that low stride frequencies and the absence of unsupported phases are ways to reduce disadvantageous branch oscillations during arboreal travel. despite these re ...	2006	16959298
repeat expansion in spinocerebellar ataxia type 17 alleles of the tata-box binding protein gene: an evolutionary approach.	the variability and mutational changes of the cag microsatellite in the tata-box binding protein gene (tbp) were studied. we sequenced the microsatellite of the tbp gene of 25 unrelated individuals from northern germany (10 sca17 patients and 15 unaffected control individuals). in addition, the microsatellites were sequenced from individuals of 10 northern german families with at least one family member affected by sca17. to study also the evolutionary history of this cag/caa microsatellite in n ...	2007	17033685
sexual swellings in wild white-handed gibbon females (hylobates lar) indicate the probability of ovulation.	conspicuous sexual swellings in the females of some primate species have been a focus of scientific interest since darwin first wrote about them in 1871. to understand these visual signals, research focused on exaggerated sexual swellings of old world primates. however, some primate species develop much smaller sexual swellings and it is as yet unclear if these smaller swellings can serve similar functions as those proposed for exaggerated swellings, i.e. advertising fertility to attract mates. ...	2007	17137580
the syntax and meaning of wild gibbon songs.	spoken language is a result of the human capacity to assemble simple vocal units into more complex utterances, the basic carriers of semantic information. not much is known about the evolutionary origins of this behaviour. the vocal abilities of non-human primates are relatively unimpressive in comparison, with gibbon songs being a rare exception. these apes assemble a repertoire of call notes into elaborate songs, which function to repel conspecific intruders, advertise pair bonds, and attract ...	2006	17183705
a high-resolution map of synteny disruptions in gibbon and human genomes.	gibbons are part of the same superfamily (hominoidea) as humans and great apes, but their karyotype has diverged faster from the common hominoid ancestor. at least 24 major chromosome rearrangements are required to convert the presumed ancestral karyotype of gibbons into that of the hominoid ancestor. up to 28 additional rearrangements distinguish the various living species from the common gibbon ancestor. using the northern white-cheeked gibbon (2n = 52) (nomascus leucogenys leucogenys) as a mo ...	2006	17196042
tempo and mode of evolution of the rh blood group genes before and after gene duplication.	the rh blood group genes became duplicated in a common ancestor of human-chimpanzee-gorilla. we compared the evolutionary rates of the rh blood group genes for each exon for branches connecting to humans, having duplicated rh loci, and to orangutan, gibbon, and old world monkeys, species having a single rh locus. our results show that evolutionary rates of nonsynonymous substitutions at exon 7 became accelerated in the human lineage. furthermore, we surveyed the sequence variation in the region ...	2007	17334753
mitochondrial dna hypervariable region-1 sequence variation and phylogeny of the concolor gibbons, nomascus.	the still little known concolor gibbons are represented by 14 taxa (five species, nine subspecies) distributed parapatrically in china, myanmar, vietnam, laos and cambodia. to set the stage for a phylogeographic study of the genus we examined dna sequences from the highly variable mitochondrial hypervariable region-1 (hvr-1 or control region) in 51 animals, mostly of unknown geographic provenance. we developed gibbon-specific primers to amplify mtdna noninvasively and obtained >477 bp sequences ...	2007	17455231
life history theory and dental development in four species of catarrhine primates.	dental development was reconstructed in several individuals representing four species of catarrhine primates--symphalangus syndactylus, hylobates lar, semnopithecus entellus priam, and papio hamadryas--using the techniques of dental histology. bar charts assumed to represent species-typical dental development were constructed from these data and estimated ages at first and third molar emergence were plotted on them along with ages at weaning, menarche, and first reproduction from the literature. ...	2007	17706270
a most distant intergeneric hybrid offspring (larcon) of lesser apes, nomascus leucogenys and hylobates lar.	unlike humans, which are the sole remaining representatives of a once larger group of bipedal apes (hominins), the "lesser apes" (hylobatids) are a diverse radiation with numerous extant species. consequently, the lesser apes can provide a valuable evolutionary window onto the possible interactions (e.g., interbreeding) of hominin lineages coexisting in the same time and place. in the present work, we employ chromosomal analyses to verify the hybrid ancestry of an individual (larcon) produced by ...	2007	17717705
home-range characteristics and the influence of seasonality on female reproduction in white-handed gibbons (hylobates lar) at khao yai national park, thailand.	a three-year (2001-2003) study was carried out on the home range characteristics of seven wild white-handed gibbon (hylobates lar) groups focusing on the spatio-temporal distribution of food resources at khao yai national park in northeastern thailand. these results were combined with 23 years (1980-2003) of reproductive performance data on seven females from the same focal groups. reproductive performance was equal among females with regard to birth, weaning and maturation ratios, and independe ...	2008	17960726
tracking the complex flow of chromosome rearrangements from the hominoidea ancestor to extant hylobates and nomascus gibbons by high-resolution synteny mapping.	in this study we characterized the extension, reciprocal arrangement, and orientation of syntenic chromosomal segments in the lar gibbon (hylobates lar, hla) by hybridization of a panel of approximately 1000 human bac clones. each lar gibbon rearrangement was defined by a splitting bac clone or by two overlapping clones flanking the breakpoint. a reconstruction of the synteny arrangement of the last common ancestor of all living lesser apes was made by combining these data with previous results ...	2008	18552313
regional variability in secondary remodeling within long bone cortices of catarrhine primates: the influence of bone growth history.	secondary intracortical remodeling of bone varies considerably among and within vertebrate skeletons. although prior research has shed important light on its biomechanical significance, factors accounting for this variability remain poorly understood. we examined regional patterning of secondary osteonal bone in an ontogenetic series of wild-collected primates, at the midshaft femur and humerus of chlorocebus (cercopithecus) aethiops (n = 32) and hylobates lar (n = 28), and the midshaft femur of ...	2008	18691379
evolutionary modifications of human milk composition: evidence from long-chain polyunsaturated fatty acid composition of anthropoid milks.	brain growth in mammals is associated with increased accretion of long-chain polyunsaturated fatty acids (lcpufa) in brain phospholipids. the period of maximum accumulation is during the brain growth spurt. humans have a perinatal brain growth spurt, selectively accumulating docosahexaenoic acid (dha) and other lcpufa from the third trimester through the second year of life. the emphasis on rapid postnatal brain growth and lcpufa transfer during lactation has led to the suggestion that human mil ...	2008	18809203
object permanence tests on gibbons (hylobatidae).	ten gibbons of various species (symphalangus syndactylus, hylobates lar, nomascus gabriellae, and nomascus leucogenys) were tested on object permanence tasks. three identical wooden boxes, presented in a linear line, were used to hide pieces of food. the authors conducted single visible, single invisible, double invisible, and control displacements, in both random and nonrandom order. during invisible displacements, the experimenter hid the object in her hand before putting it into a box. the pe ...	2008	19014264
analysis of the genetic relationships among thai gibbon species using aflp markers.	cytogenetic studies of three gibbon species using conventional banding patterns were investigated showing an identical number of 44 diploid chromosomes. they are assumed to have common evolutionary relationships. for in depth study, molecular markers were assessed using the amplified fragment length polymorphism (aflp) method. with seven successful primer combinations, a total of 1669 scorable bands were generated. the resulting bands were used for dendrogram construction. from the dendrogram, t ...	2007	19069957
milk composition of captive vervet monkey (chlorocebus pygerythrus) and rhesus macaque (macaca mulatta) with observations on gorilla (gorilla gorilla gorilla) and white handed gibbon (hylobates lar).	the nutrient content and fatty acid composition of vervet monkey milk has been determined and is compared with rhesus macaque, and two hominoid apes, the white handed gibbon and gorilla. with 15.7+/-4.1 g protein, 33.1+/-9.4 g fat, and 85.1+/-7.5 g lactose per kg milk, vervet monkey milk does not differ from that of rhesus macaque, and is within the range of other primates. small amounts (>1 g kg(-1)) of oligosaccharides, glucose, galactose and fucose were noted. in comparison, gorilla milk has ...	2009	19168147
superior olivary complex organization and cytoarchitecture may be correlated with function and catarrhine primate phylogeny.	in the mammalian auditory system, the medial nucleus of the trapezoid body and the lateral superior olive (mntb-lso system) contribute to binaural intensity processing and lateralization. localization precision varies with the sound frequencies. as recency of common ancestry with human beings increases, primates have improved low-frequency sensitivity and reduced sensitivity to higher frequencies. the medial part of the mntb is devoted to higher frequency processing. thus, its high-frequency-dep ...	2009	19184100
relic of ancient recombinations in gibbon abo blood group genes deciphered through phylogenetic network analysis.	the primate abo blood group gene encodes a glycosyl transferase (either a or b type), and is known to have large coalescence times among the allelic lineages in human. we determined nucleotide sequences of ca. 2.2kb of this gene for 23 individuals of three gibbon species (agile gibbon, white-handed gibbon, and siamang), and observed a total of 24 haplotypes. we found relics of five ancient intragenic recombinations, occurred during ca. 2-7 million years ago, through a phylogenetic network analys ...	2009	19298858
functional differences within a guild of tropical mammalian frugivores.	many plants interact with groups of mutualist pollinators and seed dispersers. a key issue for both basic ecology and conservation is whether the different species within these guilds of mutualist animals are functionally equivalent. comparing the relative effects of sympatric mutualists is important for understanding the evolution of multispecies mutualisms and for predicting mutualism stability in the face of anthropogenic change. however, empirical comparisons of the population-level impacts ...	2009	19341139
sterile pyuria in a population of wild white-handed gibbons (hylobates lar).	urinalysis is an emerging method for monitoring the health and energy balance of wild primates. here, we report the first urinalysis of wild gibbons. we used multi-reagent test strips to monitor the health status of 52 individual white-handed gibbons (hylobates lar) inhabiting khao yai national park, thailand. most urinary reference values were within normal ranges; however, regardless of age- and sex-class or monthly fruit productivity, we found unexpectedly high rates of urinary leukocytes (50 ...	2009	19514046
mechanical constraints on the functional morphology of the gibbon hind limb.	gibbons utilize a number of locomotor modes in the wild, including bipedalism, leaping and, most of all, brachiation. each locomotor mode puts specific constraints on the morphology of the animal; in some cases these may be complementary, whereas in others they may conflict. despite several studies of the locomotor biomechanics of gibbons, very little is known about the musculoskeletal architecture of the limbs. in this study, we present quantitative anatomical data of the hind limb for four spe ...	2009	19627388
are hylobates lar extirpated from china?	the nangunhe nature reserve in southwest yunnan (prc) has long been presumed to be the last stronghold of lar (or white-handed) gibbons (hylobates lar) in china and the likely last place of occurrence of hylobates lar yunnanensis. we conducted a comprehensive survey to assess the status of lar gibbons at nangunhe. we found no visual or auditory evidence of them still residing at the reserve and therefore tentatively conclude that lar gibbons have become extinct in china. it appears that large-sc ...	2009	19644553
visual preference in a human-reared agile gibbon (hylobates agilis).	visual preference was evaluated in a male agile gibbon. the subject was raised by humans immediately after birth, but lived with his biological family from one year of age. visual preference was assessed using a free-choice task in which five or six photographs of different primate species, including humans, were presented on a touch-sensitive screen. the subject touched one of them. food rewards were delivered irrespective of the subject's responses. we prepared two types of stimulus sets. with ...	2010	19882208
phylogenetic relationships and divergence dates of the whole mitochondrial genome sequences among three gibbon genera.	phylogenetic relationships of gibbons (4 genera, 12 species) deduced from short/partial mitochondrial dna sequences were with low resolution and inconsistent. their divergence over the short period of time may require longer sequences for the higher resolution. to solve the problems, we newly sequenced the whole mitochondrial genome of hylobates agilis, hylobates pileatus, nomascus sp. and symphalangus syndactylus. a highly resolved phylogenetic tree was obtained for the mitochondrial genome in ...	2010	20138221
identification of human specific gene duplications relative to other primates by array cgh and quantitative pcr.	in order to identify human lineage specific (hls) copy number differences (cnds) compared to other primates, we performed pair wise comparisons (human vs. chimpanzee, gorilla and orangutan) by using cdna array comparative genomic hybridization (cgh). a set of 23 genes with hls duplications were identified, as well as other lineage differences in gene copy number specific of chimpanzee, gorilla and orangutan. each species has gained more copies of specific genes rather than losing gene copies. el ...	2010	20153417
the pattern of the arterial supply of the pancreas in anthropoid apes, catarrhine monkeys and platyrrhine monkeys.	to get the full understanding of the arterial distribution to the pancreas, the analysis of the distribution of the variety of monkey species would be helpful. in this study, we studied the layout of the pancreatic artery in anthropoids (1 gorilla, 3 chimpanzees and 2 white-handed gibbons), in catarrhine monkeys (1 hamadryas baboon, 2 anubid baboons, 10 savannah monkeys) and in platyrrhine monkeys (6 squirrel monkeys). the pancreas of the monkeys was supplied by the arteries originating from the ...	2009	20166548
mitochondrial evidence for multiple radiations in the evolutionary history of small apes.	gibbons or small apes inhabit tropical and subtropical rain forests in southeast asia and adjacent regions, and are, next to great apes, our closest living relatives. with up to 16 species, gibbons form the most diverse group of living hominoids, but the number of taxa, their phylogenetic relationships and their phylogeography is controversial. to further the discussion of these issues we analyzed the complete mitochondrial cytochrome b gene from 85 individuals representing all gibbon species, i ...	2010	20226039
muscle moment arms of the gibbon hind limb: implications for hylobatid locomotion.	muscles facilitate skeletal movement via the production of a torque or moment about a joint. the magnitude of the moment produced depends on both the force of muscular contraction and the size of the moment arm used to rotate the joint. hence, larger muscle moment arms generate larger joint torques and forces at the point of application. the moment arms of a number of gibbon hind limb muscles were measured on four cadaveric specimens (one hylobates lar, one h. moloch and two h. syndactylus). the ...	2010	20447251
brief communication: three-dimensional motion analysis of hindlimb during brachiation in a white-handed gibbon (hylobates lar).	in brachiating gibbons, it is thought that there is little movement in the hindlimb joints and that lateral body movement is quite limited. these hypotheses are based on naked-eye observations, and no quantitative motion analyses of the hindlimbs have been reported. this study quantitatively describes the three-dimensional movements of the lower trunk and distal thigh during continuous-contact brachiation in a white-handed gibbon (hylobates lar) to evaluate the roles of the trunk and hindlimb. t ...	2010	20607695
frequent gene conversion events between the x and y homologous chromosomal regions in primates.	mammalian sex-chromosomes originated from a pair of autosomes. a step-wise cessation of recombination is necessary for the proper maintenance of sex-determination and, consequently, generates a four strata structure on the x chromosome. each stratum shows a specific per-site nucleotide sequence difference (p-distance) between the x and y chromosomes, depending on the time of recombination arrest. stratum 4 covers the distal half of the human x chromosome short arm and the p-distance of the strat ...	2010	20650009
gibbon travel paths are goal oriented.	remembering locations of food resources is critical for animal survival. gibbons are territorial primates which regularly travel through small and stable home ranges in search of preferred, limited and patchily distributed resources (primarily ripe fruit). they are predicted to profit from an ability to memorize the spatial characteristics of their home range and may increase their foraging efficiency by using a 'cognitive map' either with euclidean or with topological properties. we collected r ...	2011	21221693
first isolation of the anamorph of kazachstania heterogenica from a fatal infection in a primate host.	we describe the isolation of the anamorph of the ascomycetous yeast kazachstania heterogenica from a fatal infection in a 2 year, 9-month-old female white-handed gibbon (hylobates lar). the yeast was observed in histological sections (lung and intestine) and co-isolated with the bacterium escherichia coli from different internal organs. this is the first report of the recovery of this yeast from a fatal infection in a primate host.	2011	21539504
Nonredundancy in the dispersal network of a generalist tropical forest tree.	Plant species with generalized dispersal mutualisms are considered to be robust to local frugivore extinctions because of redundancy between dispersal agents. However, real redundancy can only occur if frugivores have similar foraging and ranging patterns and if fruit is a limiting resource. We evaluated the quantitative and qualitative contributions of seed dispersers for an endochorus mast-fruiting species, Prunus javanica (Rosaceae) in Khao Yai National Park, Thailand, to evaluate the potenti ...	2011	21870623
interspecific territoriality in gibbons (hylobates lar and h. pileatus) and its effects on the dynamics of interspecies contact zones.	we investigated the ecology and interspecific interactions of the two gibbon species (hylobates lar and h. pileatus) that overlap in distribution within a narrow zone of contact in the headwaters of the takhong river at khao yai national park in central thailand. the zone is about 10-km wide, with phenotypic hybrids comprising 6.5% of the adult population. we compared species with respect to diet, territory size, intra- and interspecific group encounters, and territory quality. the two gibbon sp ...	2012	22127502
sex ratio bias in managed populations of hylobatids.	a number of explanations have been proposed for the occurrence of sex ratio bias in primates, including the trivers-willard hypothesis on differential investment, local resource competition or enhancement as a result of sex-biased dispersal, dominance-related advantages conferred on one sex but not the other, and the fragile male hypothesis. however, none of these theories was thought to be applicable to monogamous primate species. here, we examine data on zoo-housed populations of three hylobat ...	2011	22248927
molecular evidence for the introgression between hylobates lar and h. pileatus in the wild.	inter-specific hybrid zones for hylobates gibbons are known in southeast asia. among these, one hybrid zone between hylobates lar and h. pileatus is located in khao yai national park, thailand. to find molecular evidence for the natural hybridization of the gibbons in this region, we studied mitochondrial dna (mtdna) of 68 gibbons of the h. lar phenotype living adjacent to the hybrid zone. nucleotide sequencing of a fragment of mtdna spanning hyper variable segment i showed that nine gibbons had ...	2013	22892937
soprano singing in gibbons.	diversifications in primate vocalization, including human speech, are believed to reflect evolutionary modifications in vocal anatomy and physiology. gibbon song is acoustically unique, comprising loud, melodious, penetrating pure tone-like calls. in a white-handed gibbon, hylobates lar, the fundamental frequency (f(0) ) of song sounds is amplified distinctively from the higher harmonics in normal air. in a helium-enriched atmosphere, f(0) does not shift, but it is significantly suppressed and 2 ...	2012	22926979
effects of social status and stress on patterns of gastrointestinal parasitism in wild white-handed gibbons (hylobates lar).	although gibbons (family hylobatidae) are typically monogamous, polyandrous groups occur regularly. stress associated with elevated intragroup competition among males in polyandrous groups may increase susceptibility to infectious disease. to better understand this interplay, as well as to provide the first comprehensive assessment of parasitism in free-ranging gibbons, we characterized the richness of gastrointestinal parasites and examined their prevalence in males from 14 groups (10 pair-livi ...	2013	23440877
extra-pair paternity confirmed in wild white-handed gibbons.	knowledge of the genetic mating system of animal species is essential for our understanding of the evolution of social systems and individual reproductive strategies. in recent years, genetic methods have uncovered an unexpected diversity of paternal genetic contributions across diverse animal social mating systems, but particularly in pair-living species. in most pair-living birds, for example, genetic and behavioral observations have confirmed a previously unknown significance of extra-pair co ...	2013	23877831
sexual dimorphism in relative sacral breadth among catarrhine primates.	as the sacrum contributes to the size and shape of the birth canal, the sexually dimorphic sacrum of humans is frequently interpreted within obstetric contexts. however, while the human sacrum has been extensively studied, comparatively little is known about sacral morphology in nonhuman primates. thus, it remains unclear whether sacral sexual dimorphism exists in other primates, and whether potential dimorphism is primarily related to obstetrics or other factors such as body size dimorphism. in ...	2013	24132790
locomotion behavior of cao vit gibbon (nomascus nasutus) living in karst forest in bangliang nature reserve, guangxi, china.	the cao vit gibbon is a critically endangered species. only approximately 110 individuals remain in degraded karst forest along the china-vietnam border. karst forest is unusual gibbon habitat. currently, the canopy height of cao vit gibbon habitat is approximately 10 m. research on the locomotor behavior of gibbons living in this particular forest type might provide important insight into locomotor stability and variability of gibbons. we used 5 min scan samples to record the locomotion mode, s ...	2013	24344959
cues to androgens and quality in male gibbon songs.	animal vocal signals may provide information about senders and mediate important social interactions like sexual competition, territory maintenance and mate selection. hence, it is important to understand whether vocal signals provide accurate information about animal attributes or status. gibbons are non-human primates that produce loud, distinctive and melodious vocalizations resembling more those of birds than of other non-human primates. wild gibbons are characterized by flexibility in socia ...	2013	24367551
fibre type composition in the lumbar perivertebral muscles of primates: implications for the evolution of orthogrady in hominoids.	the axial musculoskeletal system is important for the static and dynamic control of the body during both locomotor and non-locomotor behaviour. as a consequence, major evolutionary changes in the positional habits of a species are reflected by morpho-functional adaptations of the axial system. because of the remarkable phenotypic plasticity of muscle tissue, a close relationship exists between muscle morphology and function. one way to explore major evolutionary transitions in muscle function is ...	2014	24433382
the interpretive power of infraorbital foramen area in making dietary inferences in extant apes.	the infraorbital foramen (iof) is located below the orbit and transmits the sensory infraorbital nerve (ion) to mechanoreceptors located throughout the maxillary region. the size of the iof correlates with the size of the ion; thus, the iof appears to indicate relative touch sensitivity of maxillary region. in primates, iof size correlates well with diet. frugivores have relatively larger iofs than folivores or insectivores because fruit handling/processing requires increased touch sensitivity. ...	2014	24898102
locational diversity of alpha satellite dna and intergeneric hybridization aspects in the nomascus and hylobates genera of small apes.	recently, we discovered that alpha satellite dna has unique and genus-specific localizations on the chromosomes of small apes. this study describes the details of alpha satellite localization in the genera nomascus and hylobates and explores their usefulness in distinguishing parental genome sets in hybrids between these genera. fluorescence in situ hybridization was used to establish diagnostic criteria of alpha satellite dna markers in discriminating small ape genomes. in particular we establi ...	2014	25290445
the timing of spheno-occipital fusion in hominoids.	the degree of spheno-occipital fusion has been used to assign a relative age to dentally mature hominoid cranial specimens. however, a recent study of captive individuals (poe: am j phys anthropol 144 (2011) 162–165) concluded that fusion of the spheno-occipital suture in great ape taxa is of little utility for aging dentally mature individuals. in this contribution, i use dentally mature samples of extant hominoid taxa (homo sapiens, pan troglodytes schweinfurthii, gorilla gorilla gorilla, pong ...	2015	25293964
novel variable number of tandem repeats of gibbon maoa gene and its evolutionary significance.	variable number of tandem repeats (vntrs) are scattered throughout the primate genome, and genetic variation of these vntrs have been accumulated during primate radiation. here, we analyzed vntrs upstream of the monoamine oxidase a (maoa) gene in 11 different gibbon species. an abundance of truncated vntr sequences and copy number differences were observed compared to those of human vntr sequences. to better understand the biological role of these vntrs, a luciferase activity assay was conducted ...	2014	25360715
gibbon (hylobates lar) reintroduction success in phuket, thailand, and its conservation benefits.	we summarize the results from a long-term gibbon reintroduction project in phuket, thailand, and evaluate its benefits to conservation. between october 2002 and november 2012, eight breeding families of white-handed gibbons (hylobates lar) were returned to the wild in khao phra thaew non-hunting area (kpt). wild gibbons were extirpated from phuket island by the early 1980s, but the illegal wildlife trade has continued to bring young gibbons from elsewhere to the island's popular tourist areas as ...	2015	25597291
lar gibbon (hylobates lar) great call reveals individual caller identity.	gibbons (family hylobatidae) produce loud, elaborate vocalizations (songs), often in well-coordinated male/female duets. the female's great call, the most conspicuous phrase of the gibbon vocal repertoire, functions primarily to mediate territorial defense. despite the fact that lar gibbons (hylobates lar) are the most widely distributed and well researched hylobatid species and produce a rich vocal repertoire, the individual-specificity of their great calls has not previously been quantified. i ...	2015	25800578
context-specific close-range "hoo" calls in wild gibbons (hylobates lar).	close range calls are produced by many animals during intra-specific interactions, such as during home range defence, playing, begging for food, and directing others. in this study, we investigated the most common close range vocalisation of lar gibbons (hylobates lar), the 'hoo' call. gibbons and siamangs (family hylobatidae) are known for their conspicuous and elaborate songs, while quieter, close range vocalisations have received almost no empirical attention, perhaps due to the difficult obs ...	2015	25888361
species specificities among primates probed with commercially available fluorescence-based multiplex pcr typing kits.	to assess species specificities among primates of signals from short tandem repeat (str) loci included in two commercially available kits, mainly the ampflstr identifiler kit and additionally the geneprint powerplex 16 system, we analyzed 69 dna samples from 22 nonhuman primate species representing apes, old world monkeys (owms), new world monkeys (nwms), and prosimians. each prosimian species and the nwm cotton-top tamarin apparently lacked all str loci probed. only one peak, the amelogenin-x p ...	2015	25899252
comprehensive analyses of white-handed gibbon chromosomes enables access to 92 evolutionary conserved breakpoints compared to the human genome.	gibbon species (hylobatidae) impress with an unusually high number of numerical and structural chromosomal changes within the family itself as well as compared to other hominoidea including humans. in former studies applying molecular cytogenetic methods, 86 evolutionary conserved breakpoints (ecbs) were reported in the white-handed gibbon (hylobates lar, hla) with respect to the human genome. to analyze those ecbs in more detail and also to achieve a better understanding of the fast karyotype e ...	2015	25926034
long-term home range use in white-handed gibbons (hylobates lar) in khao yai national park, thailand.	ranging behavior is an important element of how nonhuman primates obtain sufficient resources to ensure biological maintenance and reproductive success. as most primates live in permanent social groups, group members must balance the benefits of group living with the costs of intragroup competition for resources. one way to mitigate the cost of intragroup feeding competition is to increase foraging-related travel, thereby increasing the number of patches visited. as a result we might expect home ...	2016	26456317
effectiveness of primate seed dispersers for an "oversized" fruit, garcinia benthamii.	the largest fruits found in tropical forests may depend on complementary seed dispersal strategies. these fruits are dispersed most effectively by megafauna, but populations can persist where megafauna are absent or erratic visitors. smaller animals often consume these large fruits, but their capacity to disperse these seeds effectively has rarely been assessed. we evaluated the contributions of gibbons (hylobates lar) and other frugivores in the seed dispersal of the megafaunal fruit garcinia b ...	2015	26649394
age related decline in female lar gibbon great call performance suggests that call features correlate with physical condition.	white-handed gibbons (hylobates lar) are small asian apes known for living in stable territories and producing loud, elaborate vocalizations (songs), often in well-coordinated male/female duets. the female great call, the most conspicuous phrase of the repertoire, has been hypothesized to function in intra-sexual territorial defense. we therefore predicted that characteristics of the great call would correlate with a caller's physical condition, and thus might honestly reflect resource holding p ...	2016	26728088
application of multicolor banding combined with heterochromatic and locus-specific probes identify evolutionary conserved breakpoints in hylobates pileatus.	the question what makes homo sapiens sapiens (hsa) special among other species is one of the basic questions of mankind. a small contribution to answer this question is to study the chromosomal constitution of hsa compared to other, closely related species. in order to check the types and extent of evolutionary conserved breakpoints we studied here for the first time the chromosomes of hylobates pileatus (hpi) compared to hsa and hylobates lar (hla) by means of molecular cytogenetics.	2016	26893612
primary bone microanatomy records developmental aspects of life history in catarrhine primates.	a central challenge in human origins research is to understand how evolution has shaped modern human life history. as fossilized remains of our ancestors provide the only direct evidence for life history evolution, efforts to reconstruct life history in paleontological contexts have focused on hard tissues, particularly on dental development. however, among investigators of other vertebrate groups, there is a long tradition of examining primary bone microstructure to decipher growth rates and ma ...	2016	26989017
comprehensive characterization of evolutionary conserved breakpoints in four new world monkey karyotypes compared to chlorocebus aethiops and homo sapiens.	comparative cytogenetic analysis in new world monkeys (nwms) using human multicolor banding (mcb) probe sets were not previously done. here we report on an mcb based fish-banding study complemented with selected locus-specific and heterochromatin specific probes in four nwms and one old world monkey (owm) species, i.e. in alouatta caraya (aca), callithrix jacchus (cja), cebus apella (cap), saimiri sciureus (ssc), and chlorocebus aethiops (cae), respectively. 107 individual evolutionary conserved ...	2015	27441227
leaf swallowing and parasite expulsion in khao yai white-handed gibbons (hylobates lar), the first report in an asian ape species.	leaf swallowing behavior, known as a form of self-medication for the control of nematode and tapeworm infection, occurs widely in all the african great apes (pan troglodytes schweinfurthii, p. t. troglodytes, p. t. verus, p. t. vellerosus, pan paniscus, gorilla gorilla graueri), except mountain gorillas. it is also reported to occur in a similar context across a wide array of other animal taxa including, domestic dogs, wolves, brown bears, and civets. despite long-term research on asian great an ...	2017	28118500
development of pelvic sexual dimorphism in hylobatids: testing the obstetric constraints hypothesis.	pelvic sexual dimorphism in primates is typically seen as the result of female-specific adaptations to obstetric constraints, which arise from the tight fit between the neonate head and the maternal pelvis. however, it remains debated to which extent pelvic dimorphism is a correlate of obstetric constraints, of body size dimorphism, and/or of other factors. also, little is known on how pelvic dimorphism develops. here we use methods of biomedical imaging and geometric morphometrics to address th ...	2017	28406562
sagittal crest formation in great apes and gibbons.	the frequency of sagittal crest expression and patterns of sagittal crest growth and development have been documented in hominoids, including some extinct hominin taxa, and the more frequent expression of the sagittal crest in males has been traditionally linked with the need for larger-bodied individuals to have enough attachment area for the temporalis muscle. in the present study, we investigate sagittal cresting in a dentally mature sample of four hominoid taxa (pan troglodytes schweinfurthi ...	2017	28418109
the ecology of white-handed and pileated gibbons in a zone of overlap and hybridization in thailand.	the study of related species in contact zones can elucidate what factors mediate species coexistence and geographical distributions. we investigated niche overlap and group interactions of two gibbon species and their hybrids co-occurring in a zone of overlap and hybridization.	2017	28726303
detection of hev-specific antibodies in four non-human primate species, including great apes, from different zoos in germany.	the hepatitis e virus (hev) has been described in humans and various animal species in different regions of the world. however, the knowledge on natural hev infection in non-human primates and the corresponding risk of zoonotic transmission is scarce. to determine whether primates in captivity are affected by hev infection, we investigated 259 individual sera of clinically healthy non-human primates of 14 species from nine german zoos. using a commercial double-antigen-sandwich elisa and a comme ...	2018	29168441
assessment of environmental enrichment for different primate species under low budget: a case study.	the 2011 european union zoo inquiry presented evidence that most zoos fail to achieve adequate levels of nonhuman animal welfare. appropriate environmental enrichment (ee) can play a role in the promotion of welfare. however, financial and staff constraints frequently make it challenging to implement ee on a daily basis. the aim of this study was to test how individuals of three different nonhuman primate species at the maia zoo in portugal (white-handed gibbons, hylobates lar; mona monkeys, cer ...	2018	29299937
an analysis of white-handed gibbon male song reveals speech-like phrases.	our goal was to document song phrases of the white-handed gibbon (hylobates lar), an asian ape that produces elaborate songs, often in well-coordinated male/female duets. we focused on the male coda, which is produced during vocal turn-taking with one's mate, and particularly its phrases containing rapid spectral and temporal variation, to investigate if modulation rates resemble those of lip-smacking in other nonhuman primates and human speech rhythm.	2018	29508909
short dispersal distance of males in a wild white-handed gibbon (hylobates lar) population.	it has long been recognized that in gibbons both sexes disperse from the natal group. however, the fate of dispersed individuals was rarely documented. here we provide the first detailed information on sex differences in dispersal patterns by analyzing the spatial genetic structure of a well-known white-handed gibbon (hylobates lar) population.	2018	29737526
a behavioural case study of early social isolation of a subadult white-handed gibbon (hylobates lar).	our aim in this study was to analyse the effects of early social isolation on the behaviour of a white-handed gibbon (hylobates lar) and at the same time to improve his level of welfare. the subject was a 6-year-old male, isolated from conspecific as well as other non-human primates since he was 3 months old. we presented the gibbon with a series of species-specific vocalisations, and we then introduced a 23-year-old conspecific female into his cage. our subject did not respond to playbacks, whe ...	2018	29874638
transcriptional activation of a chimeric retrogene pipsl in a hominoid ancestor.	retrogenes are a class of functional genes derived from the mrna of various intron-containing genes. pipsl was created through a unique mechanism, whereby distinct genes were assembled at the rna level, and the resulting chimera was then reverse transcribed and integrated into the genome by the l1 retrotransposon. expression of pipsl rna via its transcription start sites (tsss) has been confirmed in the testes of humans and chimpanzee. here, we demonstrated that pipsl rna is expressed in the tes ...	2018	30096459
pelvic sexual dimorphism among species monomorphic in body size: relationship to relative newborn body mass.	females have larger pelves than males among eutherians to mitigate obstetrical difficulty. this study addresses 3 issues concerning pelvic sexual dimorphism using 8 species that are sexually monomorphic in nonpelvic size: aotus azarae , castor canadensis , dasypus novemcinctus , hylobates lar , saguinus geoffroyi , sciurus carolinensis , sylvilagus floridanus , and urocyon cinereoargenteus . using published data to compute the index of relative newborn body mass (rnbm = [newborn body mass/adult ...	2016	30302031
the distribution, number, and certain neurochemical identities of infracortical white matter neurons in a lar gibbon (hylobates lar) brain.	we examined the number, distribution, and immunoreactivity of the infracortical white matter neuronal population, also termed white matter interstitial cells (wmics), in the brain of a lesser ape, the lar gibbon. staining for neuronal nuclear marker (neun) revealed wmics throughout the infracortical white matter, these cells being most numerous and dense close to cortical layer vi, decreasing significantly in density with depth in the white matter. stereological analysis of neun-immunopositive c ...	2019	30378128
the body center of mass in primates: is it more caudal than in other quadrupedal mammals?	whole body center of mass (bcom) position values are lacking for a comparative sample of primates. therefore, it still remains unknown whether the bcom in primates is more posteriorly located than in other mammals. the aim of the present report is to provide data for a large sample of primate species and to compare the position of the bcom in primates to non-primate mammals.	2019	30839107
intestinal parasites and the occurrence of zoonotic giardia duodenalis genotype in captive gibbons at krabokkoo wildlife breeding center, thailand.	intestinal parasitic infections can have an impact on health and growth of wildlife. the current study aims were to determine the prevalence of intestinal parasites and to molecular characterize giardia duodenalis and cryptosporidium spp. in captive gibbons at krabokkoo wildlife breeding center, thailand. fifty-five gibbons, 2 agile- (hylobates agilis), 38 lar- (hylobates lar) and 15 pileated gibbons (hylobates pileatus) were included in this study. fecal samples were collected individually at k ...	2019	31106211
infant loss during and after male replacement in gibbons.	according to the sexual selection hypothesis, infanticide during resident male replacement is an adaptive strategy that has evolved because the killing of unweaned offspring sired by previous males shortens the inter-birth intervals of the mothers whose infants are targeted and thereby increases the reproductive fitness of the perpetrator. to test this hypothesis, we describe previously unreported cases of primary male replacement for two gibbon species (hylobates lar and nomascus nasutus), and ...	2019	31338860
relationship of incisor size to diet and anterior tooth use in sympatric sumatran anthropoids.	researchers often relate anthropoid incisor size to diet and ingestive behaviors. it is suggested that primates that frequently consume large, tough foods (i.e., fruits) require large incisors to process these items. this idea has been difficult to test because of a lack of data on anterior tooth use in wild primates, and a lack of understanding concerning the relationships between food properties and ingestive behaviors. the first field study of primate ingestive behaviors has recently been com ...	1996	31918473
ontogeny and the evolution of adult body size dimorphism in apes.	this analysis investigates the ontogeny of body size dimorphism in apes. the processes that lead to adult body size dimorphism are illustrated and described. potential covariation between ontogenetic processes and socioecological variables is evaluated. mixed-longitudinal growth data from 395 captive individuals (representing hylobates lar [gibbon], hylobates syndactylus [siamang], pongo pygmaeus [orangutan], gorilla gorilla [gorilla], pan paniscus [pygmy chimpanzee], and pan troglodytes ["commo ...	1995	31924084
neonatal weight in gibbons (hylobates spp.).	neonatal and birth weights of gibbons have mostly been reported for single individuals, and larger samples (n = 2-8) have apparently been published for only two species of gibbons (hylobates lar and h. syndactylus). in addition, a critical examination of the few published neonatal weights of gibbons shows that several of them should not be used. neonatal weights are here defined as weights taken on infants up to seven days old, whereas birth weights include only those taken on the day of birth. ...	1995	31936947
lethal territorial aggression in a white-handed gibbon.	during an intergroup conflict an adult male white-handed gibbon (hylobates lar) from one group was attacked and wounded by the adult male of a neighboring group. the wounded male's calling behavior, general activity level, feeding, and participation in territorial defense declined dramatically in the days following the injury as he instead spent long periods resting and tending the wound. the normal and healthy appearance of this male prior to injury, the circumstances of the fight that caused t ...	1993	31936991
interactions between lar gibbons and pig-tailed macaques at fruit sources.	interactions are reported between white-handed gibbons (hylobates lar) and pig-tailed macaques (macaca nemestrina) in khao yai national park, thailand, in which gibbons selected ripe fruit from sources before macaques arrived on 4 occasions during june and july of 1989. the macaques foraged near gibbons or from shared fruit sources during 13% of gibbon observation time. gibbons made their presence known in fruit trees when macaques approached on 3 occasions and macaques did not enter fruit trees ...	1992	31948171
reassessment of age of sexual maturity in gibbons (hylobates spp.).	from studies of both wild and captive animals, gibbons are thought to reach sexual maturity at about 6 to 8 years of age, and the siamang (hylobates syndactylus) at about 8 to 9 years. however, a review of the literature reveals that in most cases the exact age of the maturing animals was not known and had to be estimated. this study presents seven case reports on captive gibbons of known age. captive males of the white-cheeked crested gibbon (h. leucogenys leucogenys) and of the siamang (h. syn ...	1991	31952414