Search

Gestures play an essential role in primate communication. However, little is known about how complexity of gestural use (in terms of repertoire size, intentional use, flexibility and use of gestural sequences) relates to individual and dyadic measures of sociality and whether more complex gestural use is more effective in eliciting a response. We observed 19 captive chimpanzees (

Several recent studies have highlighted that change in land use and land cover (LULC) is the main threat causing the decline and extinction of certain species. Gibbons (Hylobatidae) could be excellent examples, on account of their potential for extinction in the near future under the effects of LULC changes due to their particular ecological traits. This study aims to model the current suitable habitat of the Northern white-cheeked gibbon (Nomascus leucogenys (Ogilby, 1840)) in the Western Nghe An Biosphere Reserve (BR), Vietnam and assess the changes in its suitable habitat following the changes in LULC from 1990 to 2020. The maximum entropy approach (MaxEnt) was used to predict the suitable habitat of the gibbon using its occurrence localities and environmental predictors. The model analysis showed that the “Distance to Agriculture” variable had the strongest impact on the gibbons’ suitable habitat. Our results predicted the present suitable habitat of the gibbon species at approximately 4,022.42 km2 (30.95% of the overall BR area) in three spatially separated areas inside the Western Nghe An BR. Furthermore, the suitable habitat areas of the gibbon in 1990, 2000, and 2010 were projected at roughly 4,347.68 km2, 4,324.97 km2, and 2,750.21 km2, respectively, following a decreasing trend from 1990 to 2010, but a gradual increase between 2010 and 2020. The suitable habitat of the gibbon inside three core protected areas (Pu Mat National Park, Pu Huong, and Pu Hoat Nature Reserves) showed a continually increasing trend from 1990 to 2020. Our results highlighted the influence of LULC changes and the role of the protected area network in gibbon conservation. The information from the study provides a quantitative baseline for the future conservation of the critically endangered gibbon in the Western Nghe An BR.

Conservation translocation and reintroduction for the purpose of repopulating and reinforcing extirpated or depleted populations has been recognised as an important conservation tool, particularly for gibbon conservation in the immediate future. Feasibility assessments involving multiple factors, including taxonomic and genetic assessment of rescued and captive gibbons, are imperative prior to translocation and reintroduction programmes. In this study, we attempt to determine the subspecies and origin of captive Hylobates lar, White-handed gibbons, from Peninsular Malaysia to assist in future translocation and reintroduction programmes. A total of 12 captive and rescued H. lar samples were analysed using the control region segment of mitochondrial DNA. Sequence analyses and phylogenetic trees constructed using neighbour-joining, maximum likelihood, Bayesian inference, and network methods congruently differentiate all 12 captive individuals used in this study from other H. lar subspecies suggesting that these individuals belong to the H. lar lar subspecies. In addition, two populations of H. l. lar were observed: (1) a southern population consisting of all 12 individuals from Peninsular Malaysia, and (2) a possible northern population represented by three individuals (from previous studies), which might have originated from the region between the Isthmus of Kra, Surat Thani-Krabi depression, and Kangar-Pattani. Our findings suggest that the complete control region segment can be used to determine the subspecies and origin of captive H. lar.

Look after other species... and hark to the insightful chant of nature as you magnify the focus of human perception. This event, commented by Susan Mancino (Saint Mary's College, Notre Dame, IN), to be commented on further by Amelia Lewis (Royal Society of Biology), and chaired by William Passarini (Mansarda Acesa), is part of the activities of the 2022 International Open Seminar on Semiotics: a Tribute to John Deely on the Fifth Anniversary of His Passing, cooperatively organized by the Institute for Philosophical Studies of the Faculty of Arts and Humanities of the University of Coimbra, the Lyceum Institute, the Deely Project, Saint Vincent College, the Iranian Society for Phenomenology at the Iranian Political Science Association, the International Association for Semiotics of Space and Time, the Institute for Scientific Information on Social Sciences of the Russian Academy of Sciences, the Semiotic Society of America, the American Maritain Association, the International Association for Semiotic Studies, the International Society for Biosemiotic Studies, the International Center for Semiotics and Intercultural Dialogue, Moscow State Academic University for the Humanities and the Mansarda Acesa with the support of the FCT - Foundation for Science and Technology, I.P., of the Ministry of Science, Technology and Higher Education of the Government of Portugal under the UID/FIL/00010/2020 project. Near the end of this session we also had the distinct privilege of featuring a special, non-formal contribution from André De Tienne, the Director of the Peirce Edition Project. *** Baranna Baker is an independent scholar who explores semiotics through the lenses of quantum physics and literature. She studied philosophy under the acclaimed semiotician, John Deely, at the University of St. Thomas, Houston. In her current work, she applies semiotic principles to literature, especially as concerns the acts of writing and reading fiction. She also plays with the way the quantum world affects our perceived reality and how that reality can be explained by the interplay of semiotics and quantum physics, via the action of signs. She has been published in Semiotica, Chinese Semiotic Studies, The American Journal of Semiotics, and Semiotics, the yearbook of the Semiotic Society of America. She is the associate editor of the latter two works and has in addition edited numerous papers, articles, and books relating to the field of semiotics, including proofreading John Deely's book "On the Path of the Sign: Medieval Philosophy Redefined as the Latin Age" (read her review). She is available for freelance editing work of all kinds, with a specialty in ESL editing (English-as-a-Second-Language). *** After receiving the M.Sc. degree in Primate Behavior and Ecology from Central Washington University in 2012, Sofia Bernstein pursued her doctorate in the Departments of Ecology and Social Behavior and Cognition and Learning at the PRI - Primate Research Institute of Kyoto University, Japan. While at the PRI, Bernstein was also a member of the Leading Graduate Program in PWS - Primatology and Wildlife Science, a highly selective program for graduate students at Kyoto University, funded by the Japan Society for the Promotion of Science. As a PWS student, Sofia received additional training in animal husbandry, genetic analyses, science communication, and field work opportunities across Japan’s most famous primatological field sites. While at the PRI, Bernstein honed her science communication skills as a host and co-producer of Kyoto University’s podcast, the PrimateCast, where researchers within the field of primatology and beyond were interviewed. Sofia’s dissertation, which was supervised by Drs. Michael Huffman and Hiroki Koda, was entitled “The Vocal Repertoire of Tibetan Macaques in Mt. Huangshan, China: A Quantitative Analysis, Congeneric Comparisons, and Species-Specific Derived Calls”. Her research was the first to investigate vocalizations in this species, and Bernstein is considered one of the world’s leading experts in Tibetan macaque vocal communication. She completed her degree early in August 2016 to prepare for a position as a lecturer, and began teaching at Central Washington University as part of a dual appointment in the departments of Biological Sciences and Anthropology and Museum Studies. Bernstein has taught a wide array of courses including biostatistics, introductory courses in biology and anthropology, research methods and research design for anthropology students, and primatology specific courses at the undergraduate and graduate level. In 2017 Sofia was awarded a special appointment position that enabled her to supervise graduate students. To date, Sofia Bernstein has studied a diverse number of primate taxa, from small-bodied apes, to New and Old World monkeys. Bernstein’s field work has taken her to field sites with wild and semi-wild primates in South America and Asia, and captive care facilities throughout the United States, Japan, and Ecuador, though she mostly focus on Asian primates. Sofia’s main research interests include the evolution of acoustic signals, vocal diversity, and communicative complexity, by focusing on our closest living relatives from a comparative and multidisciplinary perspective. Investigating the evolutionary mechanisms that underpin variation in primate communication can aid in our understanding of one of the most complex puzzles in science, the origin and evolution of communication in our own species. Bernstein’s work integrates bioacoustics, behavioral ecology, and cognitive ethology, and she mostly focus on the Macaca genus. She is particularly interested in the comparison of macaque vocal repertoires by employing the same analytical techniques to shed light on the contrasting selection pressures generating variability in the genus. Sofia participates in an ongoing collaboration with Anhui University and Central Washington University at the Valley of the Wild Monkeys, China, where longitudinal data is being collected on a free-ranging troop of Tibetan macaques. Sofia Bernstein is also a participant of an ongoing collaboration with the EPRC - Endangered Primate Research Center of Vietnam, where acoustic monitoring methods are being implemented to track rehabilitated primates pre- and post-release and infer animal welfare. *** Susan Mancino is Assistant Professor at Saint Mary’s College, United States. Dr. Mancino received both her MA and PhD from Duquesne University. Her areas of expertise are Philosophy of Communication, Communication Ethics, and Semiotics. Apart from having published under premium labels such as Études Ricoeuriennes / Ricoeur Studies, Communication Research Trends, and the International Journal of Listening, she is a co-editor of An Encyclopedia of Communication Ethics: Goods in Contention (Peter Lang 2018) and Communication and Learning in an Age of Digital Transformation (Routledge 2020). *** Amelia holds a BSc (Hons) in zoology from The University of Sheffield, a master’s degree in clinical animal behaviour from the University of Lincoln, and a master’s degree in animal behaviour and welfare from The Queen’s University of Belfast (with distinction). Her research interests are in cognitive ethology and zoosemiotics, specifically animal social behaviour, communication and sensory perception. Amelia has a particular interest in domestic companion animal behaviour and human-animal interaction, and takes a biosemiotic perspective. Her publications include articles on sensory perception and communication, animal group behaviour and human-animal interaction. She has also presented at international academic conferences, including Gatherings in Biosemiotics and NASS Vilnius 2021. Previously, she has held a post as Intern Associate Editor for the journal Biosemiotics, and is a member of the Royal Society of Biology, the International Society for Biosemiotic Studies, and the Association for the Study of Animal Behaviour. *** Homepage: https://www.uc.pt/fluc/uidief/act/io2s Auditorium: https://www.uc.pt/fluc/uidief/act/io2s/auditorium *** Technical support assured by Robert Junqueira. The official graphic designer of the IO2S DEELY is Zahra Soltani Tehrani.

By identifying homogeneity in bone and soft tissue covariation patterns in living hominids, it is possible to produce facial approximation methods with interspecies compatibility. These methods may be useful for producing facial approximations of fossil hominids that are more realistic than currently possible. In this study, we conducted an interspecific comparison of the nasomaxillary region in chimpanzees and modern humans with the aim of producing a method for predicting the positions of the nasal tips of Plio-Pleistocene hominids. We addressed this aim by first collecting and performing regression analyses of linear and angular measurements of nasal cavity length and inclination in modern humans (Homo sapiens; n = 72) and chimpanzees (Pan troglodytes; n = 19), and then performing a set of out-of-group tests. The first test was performed on four subjects that belonged to the same genus as the training sample, i.e., Homo (n = 2) and Pan (n = 2), and the second test, which functioned as an interspecies compatibility test, was performed on Pan paniscus (n = 1), Gorilla gorilla (n = 3), Pongo pygmaeus (n = 1), Pongo abelli (n = 1), Symphalangus syndactylus (n = 3), and Papio hamadryas (n = 3). We identified statistically significant correlations in both humans and chimpanzees with slopes that displayed homogeneity of covariation. Prediction formulae combining these data were found to be compatible with humans and chimpanzees as well as all other African great apes, i.e., bonobos and gorillas. The main conclusion that can be drawn from this study is that our set of regression models for approximating the position of the nasal tip are homogenous among humans and African apes, and can thus be reasonably extended to ancestors leading to these clades.

All gibbon species (Primates: Hylobatidae) are facing high extinction risk due to habitat loss and hunting. The Hainan gibbon Nomascus hainanus is the world’s most critically endangered primate, and one of the priority conservation actions identified is to establish artificial canopy corridors to reconnect fragmented forests. The effectiveness of artificial canopy bridge as a conservation tool for wild gibbons has not been widely tested, and the results are rarely published. We constructed the first canopy bridge for Hainan gibbon in 2015 to facilitate passage at a natural landslide; mountaineering-grade ropes were tied to sturdy trees with the help of professional tree climbers and a camera trap was installed to monitor wildlife usage. Hainan gibbon started using the rope bridge after 176 days, and usage frequency increased with time. All members in the gibbon group crossed the 15.8 m rope bridge except adult male. Climbing was the predominant locomotor mode followed by brachiation. This study highlights the use and value of rope bridges to connect forest gaps for wild gibbons living in fragmented forests. While restoring natural forest corridors should be a priority conservation intervention, artificial canopy bridges may be a useful short-term solution.

Wet age-related macular degeneration (AMD), which can cause progressive blindness, is characterised by choroid neovascularization (CNV) in the macular area. Although close attention has been paid to AMD, and anti-vascular endothelial growth factor (VEGF) drugs are available, its complex pathogenesis is still elusive. Tie2-expressing macrophages (TEMs) have been found to promote angiogenesis in remodel tissues and tumours. This study aimed to elucidate the role of macrophage Tie2 signalling in laser-induced CNV (LCNV). We observed that TEMs were responsible for the severity of CNV. Mechanistically, TEM deletion resulted in impaired LCNV due to the suppression of inflammatory angiogenesis and the promotion of apoptosis. We also observed that TEMs prevented apoptosis of b.End3 cells, but promoted their migration, proliferation and tube formation via VEGF, extracellular signal-regulated kinase (ERK) and v-akt murine thymoma viral oncogene (AKT)-dependent signalling pathways. The flow cytometry results comparing dry AMD patients and healthy controls with wet AMD patients showed that the percentage of Tie2+CD14+ cells was higher in the wet AMD patients’ peripheral blood. This study demonstrates that Tie2 expression by macrophages intensifies CNV in LCNV murine models, thereby proposing an additional intervention option to inhibit CNV.

Background and Purpose— Our recent study demonstrated that release of Prx2 (peroxiredoxin 2) from red blood cells (RBCs) is involved in the inflammatory response and brain injury after intracerebral hemorrhage. The current study investigated the role of extracellular Prx2 in hydrocephalus development after experimental intraventricular hemorrhage. Methods— There were 4 parts in this study. First, Sprague-Dawley rats received an intraventricular injection of lysed RBC or saline and were euthanized at 1 hour for Prx2 measurements. Second, rats received an intraventricular injection of Prx2, deactivated Prx2, or saline. Third, lysed RBC was coinjected with conoidin A, a Prx2 inhibitor, or vehicle. Fourth, rats received Prx2 injection and were treated with minocycline or saline (i.p.). The effects of Prx2 and the inhibitors were examined using magnetic resonance imaging assessing ventriculomegaly, histology assessing ventricular wall damage, and immunohistochemistry to assess inflammation, particularly at the choroid plexus. Results— Intraventricular injection of lysed RBC resulted in increased brain Prx2 and hydrocephalus. Intraventricular injection of Prx2 alone caused hydrocephalus, ventricular wall damage, activation of choroid plexus epiplexus cells (macrophages), and an accumulation of neutrophils. Conoidin A attenuated lysed RBC-induced injury. Systemic minocycline treatment reduced the epiplexus cell activation and hydrocephalus induced by Prx2. Conclusions— Prx2 contributed to the intraventricular hemorrhage-induced hydrocephalus, probably by inducing inflammatory responses in choroid plexus and ventricular wall damage.

Primate limb morphology is often described as either generalized, that is, suited to a range of locomotor and positional behaviors, or specialized for unique locomotor behaviors such as brachiation or bipedalism. The evolution of highly specialized limb morphology may result in loss of evolvability, that is, in a decreased capacity of the locomotor skeleton to evolve in response to selection towards alternative ecomorphological niches. Using evolutionary simulations, I show that the highly specialized limb anatomy of hominoids is associated with a significant loss of evolvability, defined as the number of generations to reach alternative adaptive peaks, and in parallel an increased risk of extinction, particularly in simulated evolution toward generalized quadrupedal limb proportions. Loss of evolvability in apes and humans correlates with three factors: (1) decreased correlation among limb bone lengths (i.e., integration), which slows the rate of change along lines of least evolutionary resistance; (2) limb specialization, which places apes and humans in relatively remote areas of morphospace; and (3) increased skeletal size as a proxy for body size. Thus, locomotor over-specialization can lead to evolutionary dead-ends that significantly increase the probability of hominoid populations going extinct before evolving new adaptive morphologies.

This study provides the first statistically significant evidence that the mechanisms of how pair bonds are created or maintained differ between gibbon taxa. We examine the pair bond in captive pairs of three genera of gibbons (Hylobatidae): siamangs (Symphalangus, N = 17 pairs), crested gibbons (Nomascus, N = 7 pairs), and pileated gibbons (Hylobates pileatus, N = 9 pairs). In the first part of this study, we determine three generally-accepted indicators of pair-bond strength (mutual grooming, behavioral synchronization and partner distance). A pairwise comparison of our samples reveals a difference in relative partner distances between siamangs and pileated gibbons, suggesting that siamangs may have a stronger pair bond than pileated gibbons. No difference among the three taxa was found in other variables believed to indicate pair bond strength. In the second part we examine the amount of partner-directed grooming in each sex. In siamangs, males invest significantly more into pair bonds than females, whereas the opposite is true in crested and pileated gibbons. Our results for siamangs correspond to predictions derived from the ‘mate-defense hypothesis’ for the evolution of pair bonds, whereas our results for crested gibbons and pileated gibbons correspond to predictions derived from the ‘male-services hypothesis’.

Understanding flexibility in the social structure and mating strategies of the world’s last remaining population (35 individuals) of wild Hainan gibbons (Nomascus hainanus) is critical for developing effective management plans to aid in their population recovery. Three of the five remaining Hainan gibbon groups (A, B, and C) currently live in a social unit characterized by two or three adult males, two reproducing adult females, and offspring. A fourth group (D) contains one adult male, two adult females, and offspring, and Group E contains a single adult male–adult female pair with a young infant. In this study, we describe observations of copulations between multiple resident males and one of the two resident females in Group C. Group C is best described as a small multi-male/multi-female group. We found that this breeding female (F2) solicited copulations from two resident adult males (M1 and M2) on the same day, and also mated with each of these two males on different days. Resident males were not observed to interrupt the mating pair. Although factors such as a biased adult sex ratio, severe population disruption, and habitat degradation can help explain variation in group composition and mating strategies in Hainan gibbons, we argue that there exists considerable mating system variability across gibbon species, and that this variability offers important insights into male and female Hainan gibbon group structure and reproductive strategies.

The present study aimed at predicting the potential habitat of Western Hoolock Gibbon (Hoolock hoolock) in the upper Brahmaputra River Valley, Assam, India, and identifying priority conservation areas for the species, taking canopy cover into account. We used the maximum entropy algorithm for the prediction of the potential habitat of the gibbon using its current distribution with 19 environmental parameters as primary predictors. Spatio-temporal analyses of the habitat were carried out using satellite-based remote sensing and GIS techniques for two decades (1998–2018) along with Terra Modis Vegetation Continuous Field product to examine land use land cover (LULC), habitat fragmentation, Normalized Difference Vegetation Index (NDVI) and tree cover percentage of the study area. To identify the conservation priority area, we applied a cost-effective decision-making analysis using systematic conservation prioritization in R programming. The model predicted an area of 6025 km2 under high potential habitat, a major part of which was found to overlap with dense forest (80%), followed by moderately open forest (74%) and open forest (66%). The LULC change matrix showed a reduction of forest area in the predicted high potential habitat during the study period, while agricultural class showed an increasing trend. The fragmentation analysis indicated that the number of patches and patch density increased from 2008 to 2018 in the ‘very dense’ and ‘dense’ canopy regions of the gibbon habitat. Based on the conservation priority analysis, a 640 km2 area has been proposed to conserve a minimum of 10% of gibbon habitat. The current analysis revealed that in the upper Brahmaputra Valley most areas under dense forest and dense canopy have remained intact over the last two decades, at least within the high potential habitat zone of gibbons independent of the degree of area change in forest, agriculture and plantation.

It is well known that gibbons emit a pattern of vocalizations, which is specific for species and sex. A previous study showed, however, that immature southern yellow-cheeked gibbon (Nomascus gabriellae) males produce only female-like great calls from 2.3 to 5.3 years of age in co-singing interactions with their mothers. To date, nothing is known about how the vocal repertoire of a male changes from the female-like call (great call) to the male call (staccato notes and multi-modulation phrase) during vocal ontogeny. The goal of this study was to describe the transition from the female-like great call to the male call and the ontogeny of the male call. We predicted that the transition from the female-like great call to the male-specific call and the development of the male call is a normal part of the aging proces. If this is the case, the following phenomena will occur: (a) female vocalization should no longer be produced with the mature form of the multi-modulation phrase and (b) all stages of the male vocalization should occur gradually as the young male ages. Young males regularly emit both female-like great calls and male-specific calls between the ages of 5.6 to 7.1 years. Once the young males reached 7.1 years of age, they emitted male calls exclusively, and they continued to do so until the end of the observation period (at 8.11 years of age). It was confirmed that the young males emitted only female-like great calls during periods when they produced non-mature forms of a multi-modulation phrase (Fm0,1—none or one frequency modulation in second notes). Furhermore, the decrease in the number of female-like great calls was attributed to the development of the mature form of the multi-modulation phrase (Fm2—two or more frequency modulation in second notes), which developed with age. We also confirmed that the multi-modulation phrase developed gradually, while the development of the staccato notes occurred in leaps. A multi-modulation phrase developed as the initial part of the male-specific call. It was evolved from a simpler to a more complex form as the maximum frequency and age of the young males increased. Staccato notes subsequently developed in certain young males. Possible explanations for such vocal ontogeny in young males are discussed in this work.

MiR-542-3p and its target gene integrin linked kinase (ILK) in human osteosarcoma together with the differentially expressed genes from osteosarcoma tissues was analyzed through bioinformatics analysis in this study. Real time quantitative polymerase chain reaction (qRT-PCR) and western blot showed that the miR-542-3p expression decreased while the ILK expression increased in the osteosarcoma tissues. The overexpressed miR-542-3p or silenced ILK restrained cell invasion, proliferation and migration and arrested cell cycle, facilitated cell apoptosis in U-2OS and 143B cells. The dual-luciferase assay confirmed the targeting relationship between miR-542-3p and ILK. MiR-542-3p overexpression inhibited osteosarcoma growth in vivo. In conclusion, miR-542-3p overexpression down-regulated its target gene ILK, promoted osteosarcoma cells apoptosis and inhibited their proliferation, migration and invasion.

Sleeping tree selection and related behaviours of a family group and a solitary female siamang (Symphalangus syndactylus) were investigated over a 5-month period in northern Sumatra, Indonesia. We performed all day follows, sleeping tree surveys and forest plot enumerations in the field. We tested whether: (1) physical characteristics of sleeping trees and the surrounding trees, together with siamang behaviours, supported selection based on predation risk and access requirements; (2) the preferences of a solitary siamang were similar to those of a family group; and (3) sleeping site locations within home ranges were indicative of home range defence, scramble competition with other groups or other species, or food requirements. Our data showed that (1) sleeping trees were tall, emergent trees with some, albeit low, connectivity to the neighbouring canopy, and that they were surrounded by other tall trees. Siamangs showed early entry into and departure from sleeping trees, and slept at the ends of branches. These results indicate that the siamangs’ choice of sleeping trees and related behaviours were strongly driven by predator avoidance. The observed regular reuse of sleeping sites, however, did not support anti-predation theory. (2) The solitary female displayed selection criteria for sleeping trees that were similar to those of the family group, but she slept more frequently in smaller trees than the latter. (3) Siamangs selected sleeping trees to avoid neighbouring groups, monopolise resources (competition), and to be near their last feeding tree. Our findings indicate selectivity in the siamangs’ use of sleeping trees, with only a few trees in the study site being used for this purpose. Any reduction in the availability of such trees might make otherwise suitable habitat unsuitable for these highly arboreal small apes. Electronic supplementary material The online version of this article (10.1007/s10329-020-00849-8) contains supplementary material, which is available to authorized users.

Cereblon (CRBN) is a substrate receptor of the cullin-RING E3 ubiquitin ligase (CRL) complex that mediates the ubiquitination of several substrates. In this study, CRBN knockout (KO) mice exhibited decreased levels of stratum corneum hydration (SCH) and collagen I expression with an elevated protein level of matrix metalloprotease 1 (MMP1). The absence of cereblon in the skin of CRBN KO mice mimics the damage caused by narrowband ultraviolet B (NB-UVB). The primary CRBN deficient mouse embryonic fibroblasts (MEFs) undergo G2/M-arrested premature senescence via protein signaling of p38 MAPK and its dependent p53/p21pathway. The absence of CRBN induced the markers of cellular senescence, such as the senescence-associated heterochromatin foci (SAHF), SA-β-Gal staining, and p21 upregulation while the ectopic expression of CRBN reversed the phenotypes of SA-β-Gal staining and p21 upregulation. Reversion of the decreased protein level of collagen I was demonstrated after the reintroduction of the CRBN gene back into CRBN KO MEFs, validating the promising role of CRBN as a potential regulator for the function of the skin barrier and its cellular homeostasis.

Elective health checks form an important part of the preventative healthcare of many zoo-housed animals. These procedures are not without risk or financial expenditure, meaning careful cost&ndash, benefit analysis is required when determining the frequency and intensity with which they are implemented. This study evaluated the value of elective health checks (n = 74) carried out on 33 gibbons at a single UK zoological collection from 2011 to 2018. Data were categorised by health check type, animal age, clinical findings and outcome. Univariable binary logistic regression and multivariable modelling were used to identify factors associated with the likelihood of actionable (clinically significant) outcomes. In total, 51.35% of all elective health checks resulted in an actionable outcome. Elderly heath checks had 13.64 times greater odds of an actionable outcome and 34 times greater odds of a significant radiographic finding, when compared to routine (non-elderly) health checks. Our findings suggest that 75% wild longevity is a suitable threshold for identifying elderly captive gibbons and increasing health check frequency. Whilst further work is needed to ascertain whether these findings can be extrapolated to other collections and/or species, this study demonstrates how the analysis of clinical data can aid in the implementation of an effective and evidence-based preventative healthcare plan.

The fossil record of ‘lesser apes’ (i.e. hylobatids = gibbons and siamangs) is virtually non-existent before the latest Miocene of East Asia. However, molecular data strongly and consistently suggest that hylobatids should be present by approximately 20 Ma; thus, there are large temporal, geographical, and morphological gaps between early fossil apes in Africa and the earliest fossil hylobatids in China. Here, we describe a new approximately 12.5–13.8 Ma fossil ape from the Lower Siwaliks of Ramnagar, India, that fills in these long-standing gaps with implications for hylobatid origins. This ape represents the first new hominoid species discovered at Ramnagar in nearly a century, the first new Siwalik ape taxon in more than 30 years, and likely extends the hylobatid fossil record by approximately 5 Myr, providing a minimum age for hylobatid dispersal coeval to that of great apes. The presence of crown hylobatid molar features in the new species indicates an adaptive shift to a more frugivorous diet during the Middle Miocene, consistent with other proposed adaptations to frugivory (e.g. uricase gene silencing) during this time period as well.

Tropical forests are threatened worldwide due to deforestation. In South and Southeast Asia, gibbons (Hylobatidae) are important to seed dispersal and forest regeneration. Most gibbons are threatened due to deforestation. We studied the western hoolock gibbon (Hoolock hoolock) in Bangladesh to determine population size and extent of suitable habitat. We used distance sampling to estimate density across 22 sites in northeastern and southeastern Bangladesh. We used Maxent modeling to determine areas of highly suitable habitat throughout Bangladesh. Density was estimated to be 0.39 ± 0.09groups/km2, and the total estimated population was 468.96 ± 45.56 individuals in 135.31 ± 2.23 groups. The Maxent model accurately predicted gibbon distribution. Vegetation cover, isothermality, annual precipitation, elevation and mean temperature of the warmest quarter influenced distribution. Two areas in the northeast and two areas in the southeast have high potential for gibbon conservation in Bangladesh. We also found significantly more gibbons in areas that had some level of official protection. Thus, we suggest careful evaluation, comprehensive surveys and restoration of habitats identified as suitable for gibbons. We recommend bringing specific sites in the northeastern and southeastern regions under protection to secure habitat for remaining gibbon populations.

Metameric variation of molar size is in part associated with the dietary adaptations of mammals and results from slight alterations of developmental processes. Humans and great apes exhibit conspicuous variation in tooth morphology both between taxa and across tooth types. However, the manner in which metameric variation in molars emerged among apes and humans via evolutionary alterations in developmental processes remains largely unknown. In this study, we compare the enamel-dentine junction of the upper molars of humans—which closely correlates with morphology of the outer enamel surface and is less affected by wear—with that of the other extant hominoids: chimpanzees, bonobos, gorillas, orangutans, and gibbons. We used the morphometric mapping method to quantify and visualize three-dimensional morphological variation, and applied multivariate statistical analyses. Results revealed the following: 1) extant hominoids other than humans share a common pattern of metameric variation characterized by a largely linear change in morphospace; this indicates a relatively simple graded change in metameric molar shape; 2) intertaxon morphological differences become less distinct from the mesial to distal molars; and 3) humans diverge from the extant ape pattern in exhibiting a distinct metameric shape change trajectory in the morphospace. The graded shape change and lower intertaxon resolution from the mesial to distal molars are consistent with the concept of a ‘key’ tooth. The common metameric pattern observed among the extant nonhuman hominoids indicates that developmental patterns underlying metameric variation were largely conserved during ape evolution. Furthermore, the human-specific metameric pattern suggests considerable developmental modifications in the human lineage.

Newly discovered early hominin fossil scapulae have bolstered investigations of scapular shape, which have long been used to interpret behavioral variation among primates. However, unexpected similarities between Pongo and Homo - particularly in scapular spine orientation - have raised questions about the functional utility of scapular morphology and its phylogenetic context in the hominin lineage. Not surprisingly, significant disagreement surrounds disparate morphological reconstructions of the modern human/African ape last common ancestor (LCA). Our study utilizes geometric morphometric (GM) approaches - two employing homologous, anatomical landmarks and a "spine-free" alternative using 98 sliding semilandmarks along the boundary of the subscapular fossa. The landmark-based "wireframe" GM analysis principally sorted groups by spine orientation: Homo and Pongo were similar to one another with more transversely-oriented spines as compared to Hylobates and the African apes. In contrast, Homo and Gorilla clustered together in our semilandmark analysis with superoinferiorly broad blades. Pan scapulae were similar, but had more mediolaterally compressed blades and laterally-positioned superior angles. Hylobates was superoinferiorly narrow, yet obliquely expanded relative to the vertebral border. Pongo scapulae were unique among hominoids in being nearly as broad as they were long. Previously documented 'convergence' of Homo and Pongo scapulae appears to be principally driven by similarities in spine orientation, rather than overall blade shape. Therefore, we contend that it is more parsimonious to reconstruct the African ape/Homo LCA scapula as being Gorilla-like, especially in light of similar characterizations of certain fossil hominin scapulae. Accordingly, the evolution of Pan (highly oblique spine and laterally-situated superior angle) and Homo (transversely-oriented spine) scapular morphology would have involved relatively minor shifts from this ancestral condition. These results support the prevailing molecular phylogeny and provide further insight into the behavioral implications of scapular shape in the LCA and fossil hominins.

This paper presents the findings of a study conducted on the Eastern Hoolock Gibbon Hoolock leuconedys in Mehao Wildlife Sanctuary and outside to the south of the park, Arunachal Pradesh, India investigating the daily path length (DPL) and home range used by the species in two forest areas with different disturbance gradients. The four habituated groups of H. leuconedys in fragmented and contiguous forest areas, two groups in each of the forest types, showed considerable variation in their DPL ranging from 6.59m to 1019.01m with a mean distance of 192.75m (SE = ±26.48) in 73 full day observations. Although the mean DPL was recorded with very little variation across the seasons in both the forest types, it was significantly different from fragmented forest. Similarly, the home range size also varied among the groups and was estimated as the maximum for Group D (24.62ha) followed by Group E (16.28ha) in contiguous forest and Group B (2.49ha) and Group A (1.09ha) in fragmented forest. Also, there was a distinct seasonal pattern of home range used by all the study groups with largest seasonal home range in monsoon and pre-monsoon season in fragmented and contiguous forest respectively. The DPL and home range of H. leuconedys in Arunachal Pradesh has been highly affected by forest fragmentation and/or canopy discontinuity which makes the species vulnerable to hunting, predation by feral dogs and hawks and ultimately local extinction. Thus, the findings of the present research evoke the question of long term survival of the species in fragmented forests.

Living hominoids share a common body plan characterized by a gradient of derived postcranial features that distinguish them from their closest living relatives, cercopithecoid monkeys. However, the evolutionary scenario(s) that led to the derived postcranial features of hominoids are uncertain. Explanations are complicated by the fact that living hominoids vary considerably in positional behaviors, and some Miocene hominoids are morphologically, and therefore probably behaviorally, distinct from modern hominoids. Comparative studies that aim to identify morphologies associated with specific components of positional behavioral repertoires are an important avenue of research that can improve our understanding of the evolution and adaptive significance of the hominoid postcranium. Here, we employ a comparative approach to offer additional insight into the evolution of the hominoid lumbar vertebral column. Specifically, we tested whether giant pandas (Carnivora: Ailuropoda melanoleuca) converge with living hominoids on lumbar vertebral adaptations to the single component of their respective positional behavioral repertoires that they share--orthograde (i.e., upright) trunk posture. We compare lumbar vertebral morphologies of Ailuropoda to those of other living ursids and caniform outgroups (northern raccoons and gray wolves). Mirroring known differences between living hominoids and cercopithecoids, Ailuropoda generally exhibits fewer, craniocaudally shorter lumbar vertebrae with more dorsally positioned transverse processes that are more dorsally oriented and laterally directed, and taller, more caudally directed spinous processes than other caniforms in the sample. Our comparative evidence lends support to a potential evolutionary scenario in which the acquisition of hominoid-like lumbar vertebral morphologies may have evolved for generalized orthograde behaviors and could have been exapted for suspensory behavior in crown hominoids and for other locomotor specializations (e.g., brachiation) in extant lineages.

Functional comparisons of cortical bone strength properties between hominoid hallucal and pollical metapodials (Mt1 and Mc1, respectively) are lacking. Determining which of these two elements is stronger, and by how much, could be informative because the hallux and pollex are used differently both within and among extant hominoids during locomotion and manipulation (i.e., functional differentiation between autopod pairs). Here, we compare Mt1 and Mc1 midshaft cortical area, polar section modulus, and polar second moment of area, calculated from high-resolution computed tomography images in humans (n = 21), chimpanzees (n = 47), gorillas (n = 24), orangutans (n = 20), siamangs (n = 8), and gibbons (n = 21). Intraindividual comparisons between bones within species were made using paired t-tests. Log10-transformed Mt1:Mc1 ratios were created to assess relative strength asymmetry between bones, and interspecific comparisons of these proportions were made using analyses of variance. Absolute strength differences between the Mt1 and Mc1 for all variables were significantly larger in the Mt1 for all species (p

Emergent trees, which are taller than surrounding trees with exposed crowns, provide crucial services to several rainforest species especially to endangered primates such as gibbons and siamangs (Hylobatidae). Hylobatids show a preference for emergent trees as sleeping sites and for vocal displays, however, they are under threat from both habitat modifications and the impacts of climate change. Traditional plot-based ground surveys have limitations in detecting and mapping emergent trees across a landscape, especially in dense tropical forests. In this study, a method is developed to detect emergent trees in a tropical rainforest in Sumatra, Indonesia, using a photogrammetric point cloud derived from RGB images collected using an Unmanned Aerial Vehicle (UAV). If a treetop, identified as a local maximum in a Digital Surface Model generated from the point cloud, was higher than the surrounding treetops (Trees_EM), and its crown was exposed above its neighbours (Trees_SL; assessed using slope and circularity measures), it was identified as an emergent tree, which might therefore be selected preferentially as a sleeping tree by hylobatids. A total of 54 out of 63 trees were classified as emergent by the developed algorithm and in the field. The algorithm is based on relative height rather than canopy height (due to a lack of terrain data in photogrammetric point clouds in a rainforest environment), which makes it equally applicable to photogrammetric and airborne laser scanning point cloud data.