| the mid-face of lower pleistocene hominins and its bearing on the attribution of sk 847 and stw 53. | sk 847 and stw 53 have often been cited as evidence for early homo in south africa. to examine whether midfacial morphology is in agreement with these attributions, we analyze euclidean distances calculated from 3-d coordinates on the maxillae of sk 847 and stw 53, as well as australopithecus africanus (sts 5, sts 71), paranthropus robustus (sk 46, sk 48, sk 52, sk 83), early homo (knm-er 1813, knm-er 1805, knm-er 3733, knm-wt 15000), p. boisei (knm-er 406, knm-wt 17000, knm-wt 17400), gorilla g ... | 2012 | 22695253 |
| recovery potential of a western lowland gorilla population following a major ebola outbreak: results from a ten year study. | investigating the recovery capacity of wildlife populations following demographic crashes is of great interest to ecologists and conservationists. opportunities to study these aspects are rare due to the difficulty of monitoring populations both before and after a demographic crash. ebola outbreaks in central africa have killed up to 95% of the individuals in affected western lowland gorilla (gorilla gorilla gorilla) populations. assessing whether and how fast affected populations recover is ess ... | 2012 | 22649511 |
| infant-directed communication in lowland gorillas (gorilla gorilla): do older animals scaffold communicative competence in infants? | infant-directed speech is a linguistic phenomenon in which adults adapt their language when addressing infants in order to provide them with more salient linguistic information and aid them in language acquisition. adult-directed language differs from infant-directed language in various aspects, including speech acoustics, syntax, and semantics. the existence of a "gestural motherese" in interaction with infants, demonstrates that not only spoken language but also nonvocal modes of communication ... | 2012 | 22644596 |
| problem solving in great apes (pan paniscus, pan troglodytes, gorilla gorilla, and pongo abelii): the effect of visual feedback. | what kind of information animals use when solving problems is a controversial topic. previous research suggests that, in some situations, great apes prefer to use causally relevant cues over arbitrary ones. to further examine to what extent great apes are able to use information about causal relations, we presented three different puzzle box problems to the four nonhuman great ape species. of primary interest here was a comparison between one group of apes that received visual access to the func ... | 2012 | 22644115 |
| brief communication: hand preference for bimanual and unimanual feeding in captive gorillas: extension in a second colony of apes. | right-hand dominance is widely considered to be a uniquely human trait. whether nonhuman primates exhibit similar population-level hand preferences remains a topic of considerable debate. despite extensive research focusing on laterality in nonhuman primates, our interpretation of these studies is limited due to methodological issues including the lack of a common measure of hand preference and the use of tasks that may not be reliable indicators of handedness. the use of consistent methods betw ... | 2012 | 22639326 |
| facilitating play through communication: significance of teeth exposure in the gorilla play face. | primate facial expressions (fes) likely play an important role in primate society: through facial signals, individuals can potentially send and receive information and may benefit from coordinating their behavior accordingly. many primates use a relaxed open mouth (rom) facial display or “play face” (pf) during play behavior, where the mouth is open but teeth are covered. in addition to this conventional pf, however, western lowland gorillas (gorilla gorilla gorilla) also use a full pf where the ... | 2012 | 22512019 |
| severe idiopathic hypocalcemia in a juvenile western lowland gorilla, gorilla gorilla gorilla. | a 6-mo-old, male western lowland gorilla (gorilla gorilla gorilla) was evaluated because of tetany of both hands. the gorilla had alternating periods of constipation, diarrhea, and bloating since birth. a diagnosis of idiopathic hypocalcemia was based on severe hypocalcemia, a normal vitamin d level, response to oral calcium and vitamin d therapy, and eventual resolution. idiopathic hypocalcemia, an uncommon disease in neonatal humans, should be considered in young gorillas with persistent gastr ... | 2012 | 22448527 |
| genomics: gorilla gorilla gorilla. | | 2012 | 22398552 |
| the effect of body orientation on judgments of human visual attention in western lowland gorillas (gorilla gorilla gorilla). | the ability to appreciate the attentional states of others is an important element used in discerning the presence of theory of mind in an individual. whether primates are able to recognize attention, and further, use such information to predict behavior, remains contentious. in this study, six western lowland gorillas (gorilla gorilla gorilla) were tested under different conditions that aimed to investigate not only their understanding of what a human experimenter sees, but also what informatio ... | 2013 | 22390623 |
| use of buckets as tools by western lowland gorillas. | while all great apes have been documented to use tools, gorillas are arguably the least proficient tool users. in 2009, a western lowland gorilla (gorilla gorilla gorilla) at the buffalo zoo was observed using a bucket, which had been provided as part of normal enrichment, as a tool to collect water. we conducted a brief, ad libitum investigation to confirm the validity of the initial observation. we then carried out a systematic investigation of the behavior in 2010. we collected 72 hr of video ... | 2012 | 22290615 |
| metastatic endocervical adenocarcinoma in a western lowland gorilla (gorilla g. gorilla): no evidence of virus-induced carcinogenesis. | cervical cancer is the second most common cancer among women. nevertheless, similar tumours have only been rarely described in great apes. this report characterizes the pathological and molecular features of a metastatic endocervical adenocarcinoma in a western lowland gorilla (gorilla g. gorilla). | 2012 | 22273046 |
| molecular characterisation of protist parasites in human-habituated mountain gorillas (gorilla beringei beringei), humans and livestock, from bwindi impenetrable national park, uganda. | over 60 % of human emerging infectious diseases are zoonotic, and there is growing evidence of the zooanthroponotic transmission of diseases from humans to livestock and wildlife species, with major implications for public health, economics, and conservation. zooanthroponoses are of relevance to critically endangered species; amongst these is the mountain gorilla (gorilla beringei beringei) of uganda. here, we assess the occurrence of cryptosporidium, cyclospora, giardia, and entamoeba infecting ... | 2017 | 28720110 |
| body growth and life history in wild mountain gorillas (gorilla beringei beringei) from volcanoes national park, rwanda. | great apes show considerable diversity in socioecology and life history, but knowledge of their physical growth in natural settings is scarce. we characterized linear body size growth in wild mountain gorillas from volcanoes national park, rwanda, a population distinguished by its extreme folivory and accelerated life histories. | 2017 | 28464240 |
| mothers may shape the variations in social organization among gorillas. | when mothers continue to support their offspring beyond infancy, they can influence the fitness of those offspring, the strength of social relationships within their groups, and the life-history traits of their species. using up to 30 years of demographic data from 58 groups of gorillas in two study sites, this study extends such findings by showing that mothers may also contribute to differences in social organization between closely related species. female mountain gorillas remained with their ... | 2016 | 27853570 |
| variance in the reproductive success of dominant male mountain gorillas. | using 30 years of demographic data from 15 groups, this study estimates how harem size, female fertility, and offspring survival may contribute to variance in the siring rates of dominant male mountain gorillas throughout the virunga volcano region. as predicted for polygynous species, differences in harem size were the greatest source of variance in the siring rate, whereas differences in female fertility and offspring survival were relatively minor. harem size was positively correlated with of ... | 2014 | 24818867 |
| ecological divergence and talar morphology in gorillas. | gorillas occupy a variety of habitats from the west coast to eastern central africa. these habitats differ considerably in altitude, which has a pronounced effect on forest ecology. although all gorillas are obligate terrestrial knuckle-walking quadrupeds, those that live in lowland habitats eat fruits and climb more often than do those living in highland habitats. here we test the hypothesis that gorilla talus morphology falls along a morphocline that tracks locomotor function related to a more ... | 2014 | 24374860 |
| [great apes: who are they? are they able to self-medicate?]. | six great ape species (chimpanzees, bonobos, western gorillas, eastern gorillas, sumatran orangutans and bornean orangutans) live in tropical forests of africa and south-east asia. their habitat, severely threatened by deforestation, contains a vast chemical and biological diversity. during the last decade, we have isolated and identified novel pharmacologically active compounds from plants used by wild chimpanzees in kibale national park, uganda. our continuous observations over the last 12 yea ... | 2011 | 22844752 |
| variation in anthropoid vertebral formulae: implications for homology and homoplasy in hominoid evolution. | variation in vertebral formulae within and among hominoid species has complicated our understanding of hominoid vertebral evolution. here, variation is quantified using diversity and similarity indices derived from population genetics. these indices allow for testing models of hominoid vertebral evolution that call for disparate amounts of homoplasy, and by inference, different patterns of evolution. results are interpreted in light of "short-backed" (j exp zool (mol dev evol) 302b:241-267) and ... | 2012 | 22532475 |
| food selection by western gorillas (g.g. gorilla) in relation to food chemistry. | samples of stems, leaves, shoots and fruit (n=36) from lowland, african rain forest are analyzed for nutrients, digestibility and digestion-inhibiting substances. plants from which the samples are drawn are all important in the diet of western gorillas, large generalist herbivores in coastal cameroon. many of the plants are common in the early succession following disturbance to the forest. analysis of food chemistry in relation to food preference indicates that lignin, digestibility and crude p ... | 1985 | 28310671 |
| are great apes able to reason from multi-item samples to populations of food items? | inductive learning from limited observations is a cognitive capacity of fundamental importance. in humans, it is underwritten by our intuitive statistics, the ability to draw systematic inferences from populations to randomly drawn samples and vice versa. according to recent research in cognitive development, human intuitive statistics develops early in infancy. recent work in comparative psychology has produced first evidence for analogous cognitive capacities in great apes who flexibly drew in ... | 2017 | 28877364 |
| gut microbiome composition is associated with cardiac disease in zoo-housed western lowland gorillas (gorilla gorilla gorilla). | cardiac disease is a leading cause of mortality in zoo-housed western lowland gorillas (gorilla gorilla gorilla). the gut microbiome is associated with cardiac disease in humans and similarly the gut microbiome may be associated with cardiac diseases in close relatives of humans, such as gorillas. we assessed the relationship between cardiac disease and gut bacterial composition in eight zoo-housed male western lowland gorillas (n = 4 with and n = 4 without cardiac disease) utilizing 16s rrna ge ... | 2017 | 28859316 |
| using video and theater to increase knowledge and change attitudes-why are gorillas important to the world and to congo? | applying environmental education in primate range countries is an important long-term activity to stimulate pro-conservation behavior. within captive settings, mega-charismatic species, such as great apes are often used to increase knowledge and positively influence attitudes of visitors. here, we evaluate the effectiveness of a short-term video and theater program developed for a western audience and adapted to rural people living in two villages around nouabalé-ndoki national park, republic of ... | 2017 | 28846149 |
| successful management of cecal perforation and focal peritonitis in a gorilla (gorilla gorilla gorilla). | an 18-yr-old female western lowland gorilla ( gorilla gorilla gorilla) presented with acute-onset severe lethargy, bloody vaginal discharge, decreased appetite, and an abnormal posture. the gorilla was diagnosed with a ruptured cecal blind sac with severe adhesions to the right ovary. a typhlectomy and unilateral ovariectomy were performed. histologic examination identified a severe transmural circumferential typhlitis with rupture and adhesions to the infundibulum and chronic typhlitis. postope ... | 2017 | 28749298 |
| blood product transfusions in great apes: a retrospective review of 12 cases. | although the administration of blood and blood products can be lifesaving, transfusions in exotic species are less common because of the lack of knowledge of a species' blood groups, the availability of species-specific donors, and possible adverse effects. recently, blood groups were elucidated in great apes; however, few reports have been published regarding actual transfusion situations in these species. this information is critical because poorly executed transfusions can compromise already ... | 2017 | 28749288 |
| a retrospective review of western lowland gorilla (gorilla gorilla gorilla) mortality in european zoologic collections between 2004 and 2014. | an understanding of the main causes of mortality among captive gorillas is imperative to promoting their optimal care, health, and welfare. a retrospective observational review of mortality among the european zoo-housed western lowland gorilla ( gorilla gorilla gorilla) population from 2004 to 2014 was carried out. this is the first published study of mortality in this population. relevant postmortem data were requested from each collection reporting a death during the study period. age at death ... | 2017 | 28749273 |
| using demographic characteristics of populations to detect spatial fragmentation following suspected ebola outbreaks in great apes. | demographic crashes due to emerging diseases can contribute to population fragmentation and increase extinction risk of small populations. ebola outbreaks in 2002-2004 are suspected to have caused a decline of more than 80% in some western lowland gorilla (gorilla gorilla gorilla) populations. we investigated whether demographic indicators of this event allowed for the detection of spatial fragmentation in gorilla populations. | 2017 | 28661006 |
| intraspecific gestural laterality in chimpanzees and gorillas and the impact of social propensities. | a relevant approach to address the mechanisms underlying the emergence of the right-handedness/left-hemisphere language specialization of humans is to investigate both proximal and distal causes of language lateralization through the study of non-human primates' gestural laterality. we carried out the first systematic, quantitative comparison of within-subjects' and between-species' laterality by focusing on the laterality of intraspecific gestures of chimpanzees (pan troglodytes) and gorillas ( ... | 2017 | 28601632 |
| 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 time scale of recombination rate evolution in great apes. | we present three linkage-disequilibrium (ld)-based recombination maps generated using whole-genome sequence data from 10 nigerian chimpanzees, 13 bonobos, and 15 western gorillas, collected as part of the great ape genome project (prado-martinez j, et al. 2013. great ape genetic diversity and population history. nature 499:471-475). we also identified species-specific recombination hotspots in each group using a modified ldhot framework, which greatly improves statistical power to detect hotspot ... | 2016 | 26671457 |
| sexual coercion and courtship by male western gorillas. | sexual coercion and courtship are possible explanations for why male primates may direct agonistic behavior towards females. if so, then in species where females exhibit mate choice by transferring between males: (a) females who are not lactating (potential migrants) should receive more agonistic behavior than other females, (b) males should exhibit more agonistic behavior towards females during intergroup encounters than when no rival males are nearby, and (c) males should show more herding beh ... | 2016 | 26483073 |
| odor signals in wild western lowland gorillas: an involuntary and extra-group communication hypothesis. | odors constitute one of the most ancient ways of communication among animals. whereas the key role of olfactory communication is well established in insects or rodents, its contribution to primate behavior remains very speculative. in a recent report, klailova and lee [1] studied the variations of intensity of the typical steroid musk odor produced by wild adult male gorilla silverbacks during encounters with opponents from other social units (lone males or other groups). the odor intensity incr ... | 2015 | 25797709 |
| phenotypic correlates of male reproductive success in western gorillas. | sexual selection is thought to drive the evolution of sexually dimorphic traits that increase male reproductive success. despite a large degree of sexual dimorphism among haplorhine primates, phenotypic traits that may influence the reproductive success of males are largely unstudied due to long life spans and the difficulties in quantifying such traits non-invasively. here we employ digital photogrammetry of body length and crest size, as well as ranking of the gluteal muscle size, to test whet ... | 2012 | 22386152 |
| conservation. scientists say ebola has pushed western gorillas to the brink. | | 2007 | 17872416 |
| a support vector machine based method to distinguish long non-coding rnas from protein coding transcripts. | in recent years, a rapidly increasing number of rna transcripts has been generated by thousands of sequencing projects around the world, creating enormous volumes of transcript data to be analyzed. an important problem to be addressed when analyzing this data is distinguishing between long non-coding rnas (lncrnas) and protein coding transcripts (pcts). thus, we present a support vector machine (svm) based method to distinguish lncrnas from pcts, using features based on frequencies of nucleotide ... | 2017 | 29047334 |
| behavioral and hormonal responses to the availability of forage material in western lowland gorillas (gorilla gorilla gorilla). | we investigated how forage material affects indicators of welfare in three male western lowland gorillas (gorilla gorilla gorilla) at the detroit zoo. in addition to their maintenance diet and enrichment foods, the gorillas generally received forage material four times a week. from this baseline, we systematically manipulated how much forage material the group received on a weekly basis, with either daily or bi (twice)-weekly presentation of browse (mulberry, morus sp.) or alfalfa hay. we collec ... | 2017 | 29210099 |
| morphological integration in the gorilla, chimpanzee, and human neck. | although integration studies are important to understand the evolution of organisms' traits across phylogenies, vertebral integration in primates is still largely unexplored. here we describe and quantify patterns of morphological integration and modularity in the subaxial cervical vertebrae (c3-c7) in extant hominines incorporating the potential influence of size. | 2018 | 29446467 |
| biologically validating the measurement of oxytocin in western lowland gorilla (gorilla gorilla gorilla) urine and saliva using a commercial enzyme immunoassay. | the neuroendocrine hormone oxytocin, which is an important physiological driver of social behavior and bonding, is increasingly being measured in conjunction with behavior to better understand primate sociality. however, no data are available on oxytocin concentrations within the genus gorilla, even though the members of this genus are of great interest to researchers due to their close genetic relatedness to humans and their tolerance-based social system. the purpose of this study was to valida ... | 2018 | 29423533 |
| adaptive evolution of rh5 in apeplasmodiumspecies of thelaveraniasubgenus. | plasmodium falciparum, the major cause of malaria morbidity and mortality in humans, has been shown to have emerged after cross-species transmission of one of six host-specific parasites (subgenuslaverania) infecting wild chimpanzees (pan troglodytes) and western gorillas (gorilla gorilla). binding of the parasite-encoded ligand rh5 to the host protein basigin is essential for erythrocyte invasion and has been implicated in host specificity. a recent study claimed to have found two amino acid ch ... | 2018 | 29362238 |
| 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 |
| captive gorillas' manual laterality: the impact of gestures, manipulators and interaction specificity. | relationships between humans' manual laterality in non-communicative and communicative functions are still poorly understood. recently, studies showed that chimpanzees' manual laterality is influenced by functional, interactional and individual factors and their mutual intertwinement. however, what about manual laterality in species living in stable social groups? we tackled this question by studying three groups of captive gorillas (n=35) and analysed their most frequent manual signals: three m ... | 2017 | 29145029 |
| diversity of mammomonogamus (nematoda: syngamidae) in large african herbivores. | four species of mammomonogamus are known from large african herbivores. a recent study demonstrated that a single mammomonogamus species was shared by both western lowland gorillas (gorilla gorilla gorilla) and african forest elephants (loxodonta cyclotis) in central african republic, suggesting lower species diversity than previously described in literature. we examined more than 500 fecal samples collected from sympatric african forest elephants, western lowland gorillas, and african forest bu ... | 2018 | 29470712 |
| full-genome characterization of simian t-cell leukemia virus type 1 subtype b from a wild-born captivegorilla gorilla gorillawith t-cell lymphoma. | there are four lineages of primate t-cell lymphocytic viruses (human t-cell lymphocytic virus [htlv]/simian t-cell lymphocytic virus [stlv]), which are further divided into subtypes. to date, there is only one full-length htlv-1 subtype b genome available. here, we report the genome of a new stlv-1 subtype b from a 43-year-old male gorilla with t-cell lymphoma. | 2017 | 29074651 |
| 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 |
| recent decline in vegetative regeneration of bamboo (yushania alpina), a key food plant for primates in volcanoes national park, rwanda. | the african montane bamboo yushania alpina provides both habitat and food for many species in the albertine rift region. in volcanoes national park (vnp), rwanda, it is especially important as a key food resource for the endangered mountain gorilla gorilla beringei beringei and endangered golden guenon cercopithecus mitis kandti. we examined temporal and spatial variation in bamboo shoots regeneration and consumption by primates, monitored between 2013 and 2018 in 82 16-m2 plots located along tr ... | 2019 | 31506574 |
| morphometric, behavioral, and genomic evidence for a new orangutan species. | six extant species of non-human great apes are currently recognized: sumatran and bornean orangutans, eastern and western gorillas, and chimpanzees and bonobos [1]. however, large gaps remain in our knowledge of fine-scale variation in hominoid morphology, behavior, and genetics, and aspects of great ape taxonomy remain in flux. this is particularly true for orangutans (genus: pongo), the only asian great apes and phylogenetically our most distant relatives among extant hominids [1]. designation ... | 2017 | 29103940 |
| diversity and temporal dynamics of primate milk microbiomes. | milk is inhabited by a community of bacteria and is one of the first postnatal sources of microbial exposure for mammalian young. bacteria in breast milk may enhance immune development, improve intestinal health, and stimulate the gut-brain axis for infants. variation in milk microbiome structure (e.g., operational taxonomic unit [otu] diversity, community composition) may lead to different infant developmental outcomes. milk microbiome structure may depend on evolutionary processes acting at th ... | 2019 | 31219214 |
| monkeys (sapajus apella and macaca tonkeana) and great apes (gorilla gorilla, pongo abelii, pan paniscus, and pan troglodytes) play for the highest bid. | many studies investigate the decisions made by animals by focusing on their attitudes toward risk, that is, risk-seeking, risk neutrality, or risk aversion. however, little attention has been paid to the extent to which individuals understand the different odds of outcomes. in a previous gambling task involving 18 different lotteries (pelé, broihanne, thierry, call, & dufour, 2014), nonhuman primates used probabilities of gains and losses to make their decision. although the use of complex mathe ... | 2019 | 30589294 |
| high order formation and evolution of hornerin in primates. | genomic duplication or loss can accelerate evolution because the number of repeats could affect molecular pathways and phenotypes. we have previously reported that the repeated region of filaggrin (flg), a crucial component of the outer layers of mammalian skin, had high levels of nucleotide diversity with species-specific divergence and expansion and that it evolved under the birth-and-death model. we focused on hornerin (hrnr), a member of the same gene family that harbor similar tandem repeat ... | 2018 | 30256937 |
| refining the ecological brain: strong relation between the ventromedial prefrontal cortex and feeding ecology in five primate species. | to survive in complex and seasonal environments, primates are thought to rely upon cognitive capacities such as decision-making and episodic memory, which enable them to plan their daily foraging path. according to the ecological brain hypothesis, feeding ecology has driven the expansion of the brain to support the corresponding development of cognitive skills. recent works in cognitive neurosciences indicate that cognitive operations such as decision-making or subjective evaluation (which are c ... | 2019 | 31030897 |
| parasitic infections in african humans and non-human primates. | different protozoa and metazoa have been detected in great apes, monkeys and humans with possible interspecies exchanges. some are either nonpathogenic or their detrimental effects on the host are not yet known. others lead to serious diseases that can even be fatal. their survey remains of great importance for public health and animal conservation. fecal samples from gorillas (gorilla gorilla) and humans living in same area in the republic of congo, chimpanzees (pan troglodytes) from senegal an ... | 2020 | 32664573 |
| adenovirus infections in african humans and wild non-human primates: great diversity and cross-species transmission. | non-human primates (nhps) are known hosts for adenoviruses (advs), so there is the possibility of the zoonotic or cross-species transmission of advs. as with humans, adv infections in animals can cause diseases that range from asymptomatic to fatal. the aim of this study was to investigate the occurrence and diversity of advs in: (i) fecal samples of apes and monkeys from different african countries (republic of congo, senegal, djibouti and algeria), (ii) stool of humans living near gorillas in ... | 2020 | 32570742 |
| serological diagnosis of baylisascaris procyonis in primates using a human elisa test. | the usefulness of a human enzyme-linked immunosorbent assay (elisa) for serological diagnosis of baylisascaris procyonis larva migrans was assessed in nonhuman primates (nhp). the test was originally developed as an assay performed on human samples at purdue university. six participating zoos submitted 258 nhp serum samples, spanning these major phylogenetic groups: 1) great apes (n = 84), 2) lesser apes (n = 17), 3) old world monkeys (n = 84), 4) new world monkeys (n = 20), and 5) prosimians (n ... | 2019 | 31260208 |
| detection of hepatitis e virus antibodies among cercopithecidae and hominidae monkeys in cameroon. | we screened hepatitis e from 15 species of non-human primates. anti-hev igg was detected in 11.1% (1/9) mandrillus sphinx, 14.3% (2/14) gorilla gorilla, 5.9% (4/67) pan troglodytes and 8.7% (2/23) mandrillus leucophaeus, whereas anti-hev igm was detected in 1.5% (1/18) papio anubis, 28.6% (2/7) cercocebus agilis and 1.5% (1/67) pan troglodyte. | 2019 | 31179536 |
| total eclipse of the zoo: animal behavior during a total solar eclipse. | the infrequency of a total solar eclipse renders the event novel to those animals that experience its effects and, consequently, may induce anomalous behavioral responses. however, historical information on the responses of animals to eclipses is scant and often conflicting. in this study, we qualitatively document the responses of 17 vertebrate taxa (including mammals, birds, and reptiles) to the 2017 total solar eclipse as it passed over riverbanks zoo and garden in columbia, south carolina. i ... | 2020 | 32244374 |
| lowland gorillas (gorilla gorilla gorilla) failed to respond to others' yawn: experimental and naturalistic evidence. | yawn contagion, possibly a form of emotional contagion, occurs when a subject yawns in response to others' yawns. yawn contagion has been reported in humans, chimpanzees, bonobos, geladas, wolves, and dogs. in these species, individuals form strong, long-term relationships and yawn contagion is highest between closely bonded individuals. this study focuses on the possible expression of yawn contagion in western lowland gorillas (gorilla gorilla gorilla). gorillas share with geladas a similar bas ... | 2019 | 30896230 |
| comparative performance of orangutans (pongo spp.), gorillas (gorilla gorilla gorilla), and drills (mandrillus leucophaeus), in an ephemeral foraging task. | a goal of the comparative approach is to test a variety of species on the same task. here, we examined whether the factors that helped capuchin monkeys improve their performance in a dichotomous choice task would generalize to three other primate species: orangutans, gorillas, and drill monkeys. in this task, subjects have access to two options, each resulting in an identical food, but one (the ephemeral option) is only available if it is chosen first, whereas the other one (the permanent option ... | 2020 | 33135209 |
| competition, seed dispersal and hunting: what drives germination and seedling survival in an afrotropical forest? | disentangling the contributions of different processes that influence plant recruitment, such as competition and seed dispersal, is important given the increased human-mediated changes in tropical forest ecosystems. previous studies have shown that seedling communities in an afrotropical rainforest in southeastern nigeria are strongly affected by the loss of important seed-dispersing primates, including cross river gorillas (gorilla gorilla diehli), chimpanzee (pan troglodytes elioti) and drill ... | 2019 | 31024680 |
| 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 |
| hand preferences in captive gorillas, orang-utans and gibbons. | hand preference was assessed in 12 gorillas (gorilla gorilla gorilla), 13 orang-utans (pongo pygmaeus abelii), and 9 gibbons (hylobates lar) by using a floor retrieval task and a mesh retrieval task. hand preference was also assessed in 8 gorillas and 8 orang-utans by using a task involving the unfastening of a hasp. a bipedal requirement during testing (mesh retrieval task) facilitated detection of hand preferences. a significant left-hand preference was found for the gibbons with 6 of 6 gibbon ... | 1990 | 31963993 |
| nucleotide sequencing of the hoxa gene cluster using gorilla fosmid clones. | we sequenced the western gorilla (gorilla gorilla) hoxa cluster region using seven fosmid clones, and found that the total tiling path sequence was 214,185 bp from the 5' non-genic region of hoxa1 to the 3' non-genic region of evx1. we compared the nucleotide sequence with the gorilla genome sequence in the ncbi database, and the overall proportion of nucleotide difference was estimated to be 0.0005-0.0007. these estimates are lower than overall genomic polymorphism in gorillas. | 2020 | 32934753 |
| gorilla calcaneal morphological variation and ecological divergence. | the primate foot has been extensively investigated because of its role in weight-bearing; however, the calcaneus has been relatively understudied. here we examine entire gorilla calcaneal external shape to understand its relationship with locomotor behavior. | 2020 | 32871028 |
| the effect of visitors on the behavior of zoo-housed western lowland gorillas (gorilla gorilla gorilla). | primates, especially apes, are popular with the public, often attracting large crowds. these crowds could cause behavioral change in captive primates, whether positive, neutral, or negative. we examined the impact of visitors on the behavior of six western lowland gorillas (gorilla gorilla gorilla), observing the troop over 6 weeks during high season (4.5 hr/day, 35 days, may-july 2016). we used focal scan sampling to determine activity budget and enclosure usage, and focal continuous sampling t ... | 2020 | 32813293 |
| in or out: response slowing across housing conditions as a measure of affect in three western lowland gorillas (gorilla gorilla gorilla). | individuals experiencing negative affect have shown response slowing, a longer latency to respond in relation to baseline, when presented with aversive stimuli. we assessed response slowing in three male gorillas housed in a bachelor group as a function of daytime and nighttime housing arrangements. | 2020 | 32728496 |
| infant survival in western lowland gorillas after voluntary dispersal by pregnant females. | in many social species, after the alpha male has been replaced or the group disintegrates, a female's infant is at risk of infanticide by a male. female gorillas have developed the rare strategy of secondary dispersal in which they transfer between reproductive groups during the limited time period between weaning an infant and conceiving the next one (voluntary dispersal). by doing so they leave a weaker silverback near the end of his tenure and join a stronger silverback at an earlier stage of ... | 2020 | 32720106 |
| ecological correlates of space use patterns in wild western lowland gorillas. | the distribution of resources is a crucial determinant of animals' space use (e.g., daily travel distance, monthly home range size, and revisitation patterns). we examined how variation in ecological parameters affected variability in space use patterns of western lowland gorillas, gorilla gorilla gorilla. they are an interesting species for investigating this topic because key components of their diet are nonfruit items (herbaceous vegetation and tree leaves) that occur at low density and are s ... | 2020 | 32608168 |
| prior experience mediates the usage of food items as tools in great apes (pan paniscus, pan troglodytes, gorilla gorilla, and pongo abelii). | humans use tools with specific functions to solve tasks more efficiently. however, functional specialization often comes at a cost: it can hinder the production of actions that are not usually performed with those tools, thus resulting in a fixation effect (functional fixedness). little is known about whether our closest living relatives, the nonhuman great apes, are vulnerable to this detrimental effect of experience. we examined whether great apes from 4 species (n = 35) would become fixated o ... | 2020 | 32463250 |
| allostatic load indices with cholesterol and triglycerides predict disease and mortality risk in zoo-housed western lowland gorillas (gorilla gorilla gorilla). | allostatic load, or the physiological dysregulation accumulated due to senescence and stress, is an established predictor of human morbidity and mortality and has been proposed as a tool for monitoring health and welfare in captive wildlife. it is estimated by combining biomarkers from multiple somatic systems into allostatic load indices (alis), providing a score representing overall physiological dysregulation. such alis have been shown to predict disease and mortality risk in western lowland ... | 2020 | 32425494 |
| same space, different species: the influence of exhibit design on the expression of zoo-housed apes' species-typical retiring behaviors. | wild chimpanzees frequently make arboreal nests, while wild lowland gorillas typically nest on the ground. we aimed to understand whether zoo-housed apes' use of elevated spaces for retiring similarly differed between species and across exhibits. using a pre-planned exhibit switch at lincoln park zoo (chicago, usa), we compared where (elevated or terrestrial) two groups of apes (pan troglodytes and gorilla gorilla gorilla) performed retiring behaviors (inactive, sleeping, and nest-building behav ... | 2020 | 32408572 |
| variation in behavioral traits of two frugivorous mammals may lead to differential responses to human disturbance. | human activities can lead to a shift in wildlife species' spatial distribution. understanding the specific effects of human activities on ranging behavior can improve conservation management of wildlife populations in human-dominated landscapes. this study evaluated the effects of forest use by humans on the spatial distribution of mammal species with different behavioral adaptations, using sympatric western lowland gorilla and central chimpanzee as focal species. we collected data on great ape ... | 2020 | 32313637 |
| food preference and nutrient composition in captive bonobos (pan paniscus). | food preference has been studied in a range of hominoidea in the wild and in captivity, allowing for interspecific comparisons. chimpanzees (pan troglodytes) and gorillas (gorilla gorilla gorilla) prefer low-fibre, high-sugar foods, suggesting that frugivory and their dietary overlap are a result of their shared preference for the same nutrients. comparable tests of the nutritional preference of bonobos do not exist. in this study we examined food preferences of five captive bonobos for 23 famil ... | 2020 | 32246408 |
| testing a method to improve predictions of disease and mortality risk in western lowland gorillas (gorilla gorilla gorilla) using allostatic load. | allostatic load is the wear-and-tear organisms accumulate due to senescence and stress; it is measured by combining biomarkers from multiple somatic systems into allostatic load indices (alis). frequently used in human research, alis have shown consistent results across samples despite different biomarkers and methods. however, determining optimal models likely is necessary if alis are to be feasible research tools in other species. herein, we build on prior research in western lowland gorillas ... | 2020 | 32228119 |
| mandibular corpus shape is a taxonomic indicator in extant hominids. | the aim of this study is to understand whether the shape of three sub-regions of the mandibular corpus (the alveolar arch, corpus at m1 and posterior symphysis) are useful for making taxonomic assessments at the genus and species levels in extant hominids. | 2020 | 32166734 |
| gorillas' (gorilla g. gorilla) knowledge of conspecifics' affordances: intraspecific social tool use for food acquisition. | the use of tools, long thought to be uniquely human, has now been observed in other animal taxa including several species of birds, non-primate mammals as well as some non-human primate species. chimpanzees, one of humankind's closest living relatives, exceed all other non-human animal species as they have been reported to use an exceptionally large toolkit. however, relatively little is known about the tool-use skills of the other great ape species. while the majority of tools described are ina ... | 2020 | 32166437 |
| western gorilla space use suggests territoriality. | the evolutionary origins of how modern humans share and use space are often modelled on the territorial-based violence of chimpanzees, with limited comparison to other apes. gorillas are widely assumed to be non-territorial due to their large home ranges, extensive range overlap, and limited inter-group aggression. using large-scale camera trapping, we monitored western gorillas in republic of congo across 60 km2. avoidance patterns between groups were consistent with an understanding of the "ow ... | 2020 | 32165643 |
| video-mediated behavior in gorillas (gorilla gorilla gorilla): a stage in the development of self-recognition in a juvenile male? | the anomalous position of gorillas (gorilla gorilla gorilla) in the capacity for self-recognition remains puzzling. the standard measure of self-recognition is gallup's (1970) mark test that assesses an individual's ability to recognize its altered image in a mirror following the application of paint marks to visually inaccessible areas. here, the results of a small-scale pilot study are presented, utilizing video playback through a tv monitor, to examine behavioral differences indicative of dev ... | 2020 | 32162933 |
| spatial cognition in western gorillas (gorilla gorilla): an analysis of distance, linearity, and speed of travel routes. | spatial memory allows animals to retain information regarding the location, distribution, and quality of feeding sites to optimize foraging decisions. western gorillas inhabit a complex environment with spatiotemporal fluctuations of resource availability, prefer fruits when available, and travel long distances to reach them. here, we examined movement patterns-such as linearity, distance, and speed of traveling-to assess whether gorillas optimize travel when reaching out-of-sight valued resourc ... | 2020 | 32060749 |
| no evidence of what-where-when memory in great apes (pan troglodytes, pan paniscus, pongo abelii, and gorilla gorilla). | episodic memory is the ability to recollect specific past events belonging to our personal experience, and it is one of the most crucial human abilities, allowing us to mentally travel through time. in animals, however, evidence of what-where-when memory (hereafter, www memory) is limited to very few taxa, mostly reflecting the socioecological challenges faced in their environment. in this article, we aimed to replicate 2 studies previously conducted on birds and primates to find convincing evid ... | 2020 | 32052981 |
| perceptions and behaviors of indigenous populations regarding illegal use of protected area resources in east africa's mountain gorilla landscape. | illegal activities and use of park resources are the main challenges facing mountain gorilla (gorilla beringei beringei) conservation and the protection of their habitats in the east africa's greater virunga transboundary landscape (gvtl). indigenous residents around gvtl are considered the primary illegal users of park resources. despite this, there is limited understanding of the current and past perceptions of indigenous residents living in communities adjacent to two gvtl parks; volcanoes na ... | 2020 | 31938874 |
| brief communication: maximum ingested bite size in captive western lowland gorillas (gorilla gorilla gorilla). | previously, we found that maximum ingested bite size (vb ), the largest piece of food an animal can consume without biting it into smaller pieces first, isometrically scales relative to body size in strepsirrhines and with negative allometry in anthropoids. in the current study, we rectify the omission of great apes from the earlier sample to now characterize the vb of the entire size-range of the order. | 2020 | 31912896 |
| the context of chest beating and hand clapping in wild western gorillas (gorilla gorilla gorilla). | loud auditory gestures that are produced by repetitively percussing body parts are rare in primate repertoires and have been mostly observed in captive settings. gorillas produce two of the most conspicuous long-range signals of this type: chest beating and hand clapping. here we present the first systematic analysis of chest beating (n = 63) and hand clapping (n = 88) in wild western gorillas to assess the behavioral contexts in which they emerged, the flexibility of their use, and the age-sex ... | 2020 | 31894436 |
| trabecular architecture of the capitate and third metacarpal through ontogeny in chimpanzees (pan troglodytes) and gorillas (gorilla gorilla). | chimpanzees (pan troglodytes) and gorillas (gorilla gorilla) both knuckle-walk in adulthood but are known to develop their locomotor strategies differently. using dentally defined age-groups of both pan and gorilla and behavioral data from the literature, this study presents an internal trabecular bone approach to better understand the morphological ontogeny of knuckle-walking in these taxa. capitate and third metacarpal bones were scanned by μct at 23-43 μm resolution with scaled volumes of int ... | 2020 | 31805487 |
| trabecular variation in the first metacarpal and manipulation in hominids. | the dexterity of fossil hominins is often inferred by assessing the comparative manual anatomy and behaviors of extant hominids, with a focus on the thumb. the aim of this study is to test whether trabecular structure is consistent with what is currently known about habitually loaded thumb postures across extant hominids. | 2020 | 31762017 |
| evaluating changes in salivary oxytocin and cortisol following positive reinforcement training in two adult male western lowland gorillas (gorilla gorilla gorilla). | positive reinforcement training (prt) is associated with increases in species-typical behavior and decreases in stereotypic and abnormal behavior in participating animals. physiological changes following prt, for example, increases in oxytocin (oxt) and/or decreases in cortisol (cort), may facilitate these behavioral changes. this study evaluated salivary oxt and salivary cort concentrations in two adult male western lowland gorillas (gorilla gorilla gorilla) following prt with their primary ani ... | 2020 | 31746026 |
| potential adaptations for bipedalism in the thoracic and lumbar vertebrae of homo sapiens: a 3d comparative analysis. | a number of putative adaptations for bipedalism have been identified in the hominin spine. however, it is possible that some have been overlooked because only a few studies have used 3d and these studies have focused on cervical vertebrae. with this in mind, we used geometric morphometric techniques to compare the 3d shapes of three thoracic and two lumbar vertebrae of homo sapiens, pan troglodytes, gorilla gorilla, and pongo pygmaeus. the study had two goals. one was to confirm the existence of ... | 2019 | 31711026 |
| faster growth corresponds with shallower linear hypoplastic defects in great ape canines. | deeper or more 'severe' linear enamel hypoplasia (leh) defects are hypothesized to reflect more severe stress during development, but it is not yet clear how depth is influenced by intrinsic enamel growth patterns. recent work documented inter- and intraspecific differences in leh defect depth in extant great apes, with mountain gorillas having shallower defects than other taxa, and females having deeper defects than males. here, we assess the correspondence of inter- and intraspecific defect de ... | 2019 | 31704354 |
| pelvic shape variation among gorilla subspecies: phylogenetic and ecological signals. | gorillas occupy habitats that range in elevation from 0 to 3850 m. populations at higher elevations tend to be less arboreal than lowland populations. variation in habitat-specific behaviors among closely related populations makes gorillas a unique model to study the relationship between locomotion and morphology. the pelvis reflects differences in locomotion in other primates, and thus may also reflect locomotor differences among gorillas. we tested the hypothesis that pelvic morphology exhibit ... | 2019 | 31669913 |
| nutritional composition of the diet of the western gorilla (gorilla gorilla): interspecific variation in diet quality. | to meet nutritional needs, primates adjust their diets in response to local habitat differences, though whether these dietary modifications translate to changes in dietary nutrient intake is unknown. a previous study of two populations of the mountain gorilla (mg: gorilla beringei) found no evidence for intraspecific variation in the nutrient composition of their diets, despite ecological and dietary differences between sites. one potential explanation is that nutritional variability in primate ... | 2019 | 31463957 |
| reaction to allospecific death and to an unanimated gorilla infant in wild western gorillas: insights into death recognition and prolonged maternal carrying. | it is still unclear to what extent animals possess knowledge of death. primates display a large variety and often contradictory behaviors toward conspecific corpses, particularly those of infants (e.g., prolonged carrying and care). this study reports on reactions in a wild, habituated western gorilla group (gorilla gorilla, 11-13 individuals) in the central african republic to an unanimated conspecific infant, and to an allospecific corpse. individuals' reactions were compared to their usual be ... | 2020 | 31444648 |
| high-tech and tactile: cognitive enrichment for zoo-housed gorillas. | the field of environmental enrichment for zoo animals, particularly great apes, has been revived by technological advancements such as touchscreen interfaces and motion sensors. however, direct animal-computer interaction (aci) is impractical or undesirable for many zoos. we developed a modular cuboid puzzle maze for the troop of six western lowland gorillas (gorilla gorilla gorilla) at bristol zoo gardens, united kingdom. the gorillas could use their fingers or tools to interact with interconne ... | 2019 | 31354581 |
| cardiac disease is linked to adiposity in male gorillas (gorilla gorilla gorilla). | cardiac disease is a major cause of morbidity and mortality for adult gorillas. previous research indicates a sex-based difference with predominantly males demonstrating evidence of left ventricular hypertrophy. to evaluate these findings, we analyzed serum markers with cardiac measures in a large sample of gorillas. the study sample included 44 male and 25 female gorillas housed at american association of zoo and aquariums (aza)-accredited zoos. serum samples were collected from fasted gorillas ... | 2019 | 31242268 |
| three-dimensional geometric morphometric analysis of the distal radius insertion sites of the palmar radiocarpal ligaments in hominoid primates. | to identify anatomic differences in the insertion sites of the palmar radiocarpal ligaments in different species of hominoid primates that may be related to their different types of locomotion. | 2019 | 31215639 |
| mapping gastrointestinal gene expression patterns in wild primates and humans via fecal rna-seq. | limited accessibility to intestinal epithelial tissue in wild animals and humans makes it challenging to study patterns of intestinal gene regulation, and hence to monitor physiological status and health in field conditions. to explore solutions to this limitation, we have used a noninvasive approach via fecal rna-seq, for the quantification of gene expression markers in gastrointestinal cells of free-range primates and a forager human population. thus, a combination of poly(a) mrna enrichment a ... | 2019 | 31200636 |
| a mathematical landmark-based method for measuring worn molars in hominoid systematics. | worn teeth pose a major limitation to researchers in the fields of extinct and extant hominoid systematics because they lack clearly identifiable anatomical landmarks needed to take measurements on the crown enamel surface and are typically discarded from a study. this is particularly detrimental when sample sizes for some groups are already characteristically low, if there is an imbalance between samples representing populations, sexes or dietary strategies, or if the worn teeth in question are ... | 2019 | 31198638 |
| disease avoidance, and breeding group age and size condition the dispersal patterns of western lowland gorilla females. | social dispersal is an important feature of population dynamics. when female mammals occur in polygynous groups, their dispersal decisions are conditioned by various female-, male-, and group-related factors. among them, the influence of disease often remains difficult to assess. to address this challenge, we used long-term monitoring data from two gorilla populations (gorilla gorilla gorilla) affected by infectious skin disease lesions. after controlling for other potentially influential factor ... | 2019 | 31188468 |
| first metatarsal trabecular bone structure in extant hominoids and swartkrans hominins. | changes in first metatarsal (mt1) morphology within the hominin clade are crucial for reconstructing the evolution of a forefoot adapted for human-like gait. studies of the external morphology of the mt1 in humans, non-human apes, and fossil hominins have documented changes in its robusticity, epiphyseal shape and its articulation with the medial cuneiform. here, we test whether trabecular structure in the mt1 reflects different loading patterns in the forefoot across extant large apes and human ... | 2019 | 31182196 |
| alveolar echinococcosis in western lowland gorillas (gorilla gorilla gorilla): albendazole was not able to stop progression of the disease. | echinococcus multilocularis is the etiologic agent of alveolar echinococcosis (ae), a severe and potentially fatal larval cestode infection primarily affecting the liver. ae is known to occur in dead-end intermediate hosts, including humans and nonhuman primates. between 1999 and 2016, ae was diagnosed in seven western lowland gorillas (gorilla gorilla gorilla), all from a swiss zoo. six gorillas died of the disease. one individual is still alive, receives continuous albendazole medication, and ... | 2019 | 31120685 |
| metacarpal trabecular bone varies with distinct hand-positions used in hominid locomotion. | trabecular bone remodels during life in response to loading and thus should, at least in part, reflect potential variation in the magnitude, frequency and direction of joint loading across different hominid species. here we analyse the trabecular structure across all non-pollical metacarpal distal heads (mc2-5) in extant great apes, expanding on previous volume of interest and whole-epiphysis analyses that have largely focused on only the first or third metacarpal. specifically, we employ both a ... | 2019 | 31099419 |
| comparative chemical analysis of body odor in great apes. | olfaction is important across the animal kingdom for transferring information on, for example, species, sex, group membership, or reproductive parameters. its relevance has been established in primates including humans, yet research on great apes still is fragmentary. observational evidence indicates that great apes use their sense of smell in various contexts, but the information content of their body odor has not been analyzed. our aim was therefore to compare the chemical composition of body ... | 2019 | 31094019 |
| the distribution of plant consumption traits across habitat types and the patterns of fruit availability suggest a mechanism of coexistence of two sympatric frugivorous mammals. | understanding the mechanisms governing the coexistence of organisms is an important question in ecology, and providing potential solutions contributes to conservation science. in this study, we evaluated the contribution of several mechanisms to the coexistence of two sympatric frugivores, using western lowland gorillas (gorilla gorilla gorilla) and central chimpanzees (pan troglodytes troglodytes) in a tropical rainforest of southeast cameroon as a model system. we collected great ape fecal sam ... | 2019 | 31031921 |
| gut microbiome composition of wild western lowland gorillas is associated with individual age and sex factors. | environmental and ecological factors, such as geographic range, anthropogenic pressure, group identity, and feeding behavior are known to influence the gastrointestinal microbiomes of great apes. however, the influence of individual host traits such as age and sex, given specific dietary and social constraints, has been less studied. the objective of this investigation was to determine the associations between an individual's age and sex on the diversity and composition of the gut microbiome in ... | 2019 | 31025322 |