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Alan R. Mootnick - One of the best experts on this subject based on the ideXlab platform.
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2016Co-Authors: Lucia Carbone, Alan R. Mootnick, Mariano Rocchi, Oronzo Capozzi, Nicoletta Archidiacono, Alan R. Harris, Ar Milosavljevic, Ik Martin, Miriam K, Jerilyn A. WalkerAbstract:remodeling in Hoolock leuconedys (Hylobatidae) by a new transposabl
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The Evolution of Technical Intelligence: Perspectives from the Hylobatidae
Developments in Primatology: Progress and Prospects, 2016Co-Authors: Clare L. Cunningham, James R. Anderson, Alan R. MootnickAbstract:Gibbons and siamangs (Hylobatidae), taxonomically apes, have been largely ignored in cognitive research. However, given their unique phylogenetic position, representing an intermediary divergence between monkeys and great apes, and diversity of extant genera, they are ideally placed to study the evolution of cognitive abilities in the hominoid line. This chapter presents a brief review of what is known about the use of objects as tools in the small apes. It also evaluates their understanding of the physical world through object manipulation and tool-use, predominantly based on studies conducted over the last 6 years on gibbons and siamangs housed at the Gibbon Conservation Center (GCC) in California. In a raking-in task, gibbons evidenced potentially insightful comprehension of object relationships when tool and goal were presented in direct alignment. Once the necessary relationships between tool and goal object were not physically situated in the task layout, gibbons performed poorly. This is unexpected given the taxonomic position of the Hylobatidae and their level of cortical development. However, given their unique socio-ecological adaptations, this may reflect differences in cognitive organisation rather than deficiencies.
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Phylogenetic Separation in Limb Use in Captive Gibbons (Hylobatidae): A Comparison Across the Primate Order
American journal of primatology, 2012Co-Authors: Alan R. Mootnick, Clare L. Cunningham, Elaine BakerAbstract:Although there have been few studies of self-scratching in primates, some have reported distinct differences in whether hands or feet are used, and these variations seem to reflect the evolutionary history of the Order. Monkeys and prosimians use both hands and feet to self-scratch while African great apes use hands almost exclusively. Gibbons represent an evolutionary divergence between monkeys and great apes and incidental observations at the Gibbon Conservation Center pointed to a difference in self-scratching among the four extant gibbon genera (Hoolock, Nomascus, Symphalangus, and Hylobates). To validate and further explore these preliminary observations, we collected systematic data on self-scratching from 32 gibbons, including nine species and all four genera. To supplement gibbon data, we also collected self-scratching information from 18 great apes (four species), five prosimians (two species), 26 New World Monkeys (nine species) and 20 Old World Monkeys (seven species). All monkeys and some prosimians used both hands and feet to self-scratch, whereas one prosimian species used only feet. All African great apes used hands exclusively (orangutans were an exception displaying occasional foot-use). This appears to represent a fundamental difference between monkeys and great apes in limb use. Interestingly, there was a clear difference in self-scratching between the four gibbon genera. Hylobates and Symphalangus self-scratched only with hands (like all African great apes), while Hoolock and Nomascus self-scratched with both hands and feet (like monkeys and prosimians). This difference in gibbon behavior may reflect the evolutionary history of gibbons as Hoolock and Nomascus are thought to have evolved before both Hylobates and Symphalangus. What evolutionary pressures led to this divergent pattern is currently opaque; however, this shift in limb preference may result from niche separation across the order facilitating differences in the behavioral repertoire associated with hind and forelimbs.
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An Alu-based phylogeny of gibbons (Hylobatidae)
Molecular biology and evolution, 2012Co-Authors: Thomas J. Meyer, Alan R. Mootnick, Christian Roos, Adam T. Mclain, J. Michael Oldenburg, Christopher Faulk, Matthew G. Bourgeois, Erin M. Conlin, Pieter J. De Jong, Lucia CarboneAbstract:Gibbons (Hylobatidae) are small, arboreal apes indigenous to Southeast Asia that diverged from other apes ∼15–18 Ma. Extant lineages radiated rapidly 6–10 Ma and are organized into four genera (Hylobates, Hoolock, Symphalangus, and Nomascus) consisting of 12–19 species. The use of short interspersed elements (SINEs) as phylogenetic markers has seen recent popularity due to several desirable characteristics: the ancestral state of a locus is known to be the absence of an element, rare potentially homoplasious events are relatively easy to resolve, and samples can be quickly and inexpensively genotyped. During radiation of primates, one particular family of SINEs, the Alu family, has proliferated in primate genomes. Nomascus leucogenys (northern white-cheeked gibbon) sequences were analyzed for repetitive content with RepeatMasker using a custom library. The sequences containing Alu elements identified as members of a gibbon-specific subfamily were then compared with orthologous positions in other primate genomes. A primate phylogenetic panel consisting of 18 primate species, including 13 gibbon species representing all four extant genera, was assayed for all loci, and a total of 125 gibbon-specific Alu insertions were identified. The resulting amplification patterns were used to generate a phylogenetic tree. We demonstrate significant support for Symphalangus as the most basal lineage within the family. Our findings also place Nomascus as a derived lineage, sister to Hoolock, with the Nomascus–Hoolock clade sister to Hylobates. Further, our analysis groups N. leucogenys and Nomascus siki as sister taxa to the exclusion of the other Nomascus species assayed. This study represents the first use of SINEs to determine the genus level phylogenetic relationships within the family Hylobatidae. These relationships have been resolved with robust support at most internal nodes, demonstrating the utility of SINE-based phylogenetic analysis. We postulate that hybridization and rapid radiation may have contributed to the complex and contradictory findings of the previous studies. Our findings will aid in the conservation of these threatened primates and inform future studies of the biogeographical history and distribution of modern gibbon species.
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Centromere Remodeling in Hoolock leuconedys (Hylobatidae) by a New Transposable Element Unique to the Gibbons
Genome biology and evolution, 2012Co-Authors: Lucia Carbone, R. Alan Harris, Alan R. Mootnick, Aleksandar Milosavljevic, David I. K. Martin, Mariano Rocchi, Oronzo Capozzi, Nicoletta Archidiacono, Miriam K. Konkel, Jerilyn A. WalkerAbstract:Gibbons (Hylobatidae) shared a common ancestor with the other hominoids only 15-18 million years ago. Nevertheless, gibbons show very distinctive features that include heavily rearranged chromosomes. Previous observations indicate that this phenomenon may be linked to the attenuated epigenetic repression of transposable elements (TEs) in gibbon species. Here we describe the massive expansion of a repeat in almost all the centromeres of the eastern hoolock gibbon (Hoolock leuconedys). We discovered that this repeat is a new composite TE originating from the combination of portions of three other elements (L1ME5, AluSz6, and SVA_A) and thus named it LAVA. We determined that this repeat is found in all the gibbons but does not occur in other hominoids. Detailed investigation of 46 different LAVA elements revealed that the majority of them have target site duplications (TSDs) and a poly-A tail, suggesting that they have been retrotransposing in the gibbon genome. Although we did not find a direct correlation between the emergence of LAVA elements and human-gibbon synteny breakpoints, this new composite transposable element is another mark of the great plasticity of the gibbon genome. Moreover, the centromeric expansion of LAVA insertions in the hoolock closely resembles the massive centromeric expansion of the KERV-1 retroelement reported for wallaby (marsupial) interspecific hybrids. The similarity between the two phenomena is consistent with the hypothesis that evolution of the gibbons is characterized by defects in epigenetic repression of TEs, perhaps triggered by interspecific hybridization.
Thomas Geissmann - One of the best experts on this subject based on the ideXlab platform.
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Taxon-Specific Pair Bonding in Gibbons (Hylobatidae)
Primates [Working Title], 2020Co-Authors: Thomas Geissmann, Simone Rosenkranz-weck, Judith Van Der Loo, Mathias Orgeldinger, G A LameedAbstract: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’.
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Gibbon Journal Nr. 5 – 2009 61
2015Co-Authors: Thomas Geissmann, Gustl AnzenbergerAbstract:Hormonal correlates of the ovarian cycle in the yellow-cheeked crested gibbon (Nomascus gabriellae), and a review of ovarian cycles in gibbons (Hylobatidae
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Longevity in gibbons (Hylobatidae)
2009Co-Authors: Thomas Geissmann, Katja Geschke, Barbara J. BlanchardAbstract:A longevity record of 60 years spent in captivity by a Mueller’s gibbon (Hylobates muelleri) is reported here. This appears to be the second-highest age so far reported for a non-human primate, but it is especially remarkable when adjusted for body size. It is well known that longevity in mammals correlates with body weight. Small apes should, therefore, be expected to exhibit lower longevity than the great apes because of their lower body weight. However, the longevity record for Hylobates reverses this expectation for great apes like orangutans (Pongo) and gorillas (Gorilla). This study further found a significant correlation between the captive population size of primate genera and their recorded longevity. A comparison of longevity and captive population size suggests that recorded longevity in the gibbon genera Hoolock, Nomascus and Symphalangus is lower than that of the genus Hylobates because Hylobates is kept in captivity in much higher numbers. As a result, data on Hylobates longevity are obtained from larger sample sizes than that of all other gibbons. This suggests that all gibbon genera may eventually be revealed to exhibit an elevated longevity in relation to their body weight when larger amounts of data become available. Longevity data for great apes, in contrast, are based on larger samples than those for most genera of the small apes, and an increase in sample size for great ape genera may less likely produce a substantial increase in the longevity record.
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A complete species-level phylogeny of the Hylobatidae based on mitochondrial ND3-ND4 gene sequences.
Molecular phylogenetics and evolution, 2005Co-Authors: Zoltan Takacs, Thomas Geissmann, Juan Carlos Morales, Don J. MelnickAbstract:Abstract The Hylobatidae (gibbons) are among the most endangered primates and their evolutionary history and systematics remain largely unresolved. We have investigated the species-level phylogenetic relationships among hylobatids using 1257 bases representing all species and an expanded data set of up to 2243 bases for select species from the mitochondrial ND3–ND4 region. Sequences were obtained from 34 individuals originating from all 12 recognized extant gibbon species. These data strongly support each of the four previously recognized clades or genera of gibbons, Nomascus , Bunopithecus , Symphalangus , and Hylobates , as monophyletic groups. Among these clades, there is some support for either Bunopithecus or Nomascus as the most basal, while in all analyses Hylobates appears to be the most recently derived. Within Nomascus , Nomascus sp. cf. nasutus is the most basal, followed by N. concolor , and then a clade of N. leucogenys and N. gabriellae . Within Hylobates , H. pileatus is the most basal, while H. moloch and H. klossii clearly, and H. agilis and H. muelleri likely form two more derived monophyletic clades. The segregation of H. klossii from other Hylobates species is not supported by this study. The present data are (1) consistent with the division of Hylobatidae into four distinct clades, (2) provide the first genetic evidence for all the species relationships within Nomascus , and (3) call for a revision of the current relationships among the species within Hylobates . We propose a phylogenetic tree as a working hypothesis against which intergeneric and interspecific relationships can be tested with additional genetic, morphological, and behavioral data.
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A SURVEY OF THE TAXONOMIC STATUS OF CAPTIVE GIBBONS IN TAIWAN
2004Co-Authors: Hou-chun Chen, Thomas Geissmann, Taipei Zoo, Pao-chung ChenAbstract:The gibbons or small apes (Hylobatidae) of South-east Asia include several highly endangered species. In the 1980s, gibbons were very popular in Taiwan as pets and were imported into the country in high numbers. Their diversity as well as the abnormal presence of captive-bred hybrids frequently causes problems in species identification. Given the importance of taxa identification as a necessary step for conservation, we conducted a survey of the captive gibbon population in Taiwan. We applied morphological analysis, DNA analysis, and vocal identification to identify the numerous gibbon species. Our 2002 survey revealed 83 gibbons of eight species in Taiwan. Our findings correct the original records in zoos and rescue centers and will help to prevent further hybridization. The results of this survey will be useful in establishing breeding programs and for improving ex-situ conservation of gibbon species in Taiwan. Finally, this study provides a template for similar work on captive gibbon identification elsewhere.
J. M. Le Minor - One of the best experts on this subject based on the ideXlab platform.
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The popliteal sesamoid bone (cyamella) in primates
American journal of physical anthropology, 1992Co-Authors: J. M. Le MinorAbstract:A study of 246 adult nonhuman primates belonging to 34 genera indicates that a popliteal sesamoid bone is always present in the tendon of the popliteus muscle in Prosimii and Callitrichidae. The bone occurs only variably in Atelidae and Pongo, and is usually absent in Gorilla. The bone is absent, or very rare, in Cebus, Cercopithecidae, Hylobatidae, Pan, and humans. When the bone is present, it articulates with the posterior part of the articular surface of the lateral condyle of the tibia, and lies very close to the head of the fibula, at the angulated part of the popliteal tendon, near the tendomuscular junction. The presence of the popliteal sesamoid bone in primates is a primitive character.
O. Frank Huffman - One of the best experts on this subject based on the ideXlab platform.
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The oldest gibbon fossil (Hylobatidae) from insular Southeast Asia: evidence from Trinil, (East Java, Indonesia), Lower/Middle Pleistocene.
PloS one, 2014Co-Authors: Thomas Ingicco, John De Vos, O. Frank HuffmanAbstract:A fossil femur excavated by Eugene Dubois between 1891–1900 in the Lower/Middle Pleistocene bonebed of the Trinil site (Java, Indonesia) was recognised by us as that of a Hylobatidae. The specimen, Trinil 5703 of the Dubois Collection (Leiden, The Netherlands), has the same distinctive form of fossilization that is seen in many of the bonebed fossils from Trinil in the collection. Anatomical comparison of Trinil 5703 to a sample of carnivore and primate femora, supported by morphometric analyses, lead to the attribution of the fossil to gibbon. Trinil 5703 therefore provides the oldest insular record of this clade, one of the oldest known Hylobatidae fossils from Southeast Asia. Because living Hylobatidae only inhabit evergreen rain forests, the paleoenvironment within the river drainage in the greater Trinil area evidently included forests of this kind during the Lower/Middle Pleistocene as revealed here.
Muhammad Iqbal - One of the best experts on this subject based on the ideXlab platform.
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Fire, demography and the persistence of siamang (Symphalangus syndactylus: Hylobatidae) in a Sumatran rainforest
Animal Conservation, 2003Co-Authors: Timothy G. O'brien, Margaret F. Kinnaird, Anton Nurcahyo, Maya D. Prasetyaningrum, Muhammad IqbalAbstract:We show a direct impact of El Nino/Southern Oscillation (ENSO) related fires on the demography and persistence of the siamang (Symphalangus syndactylus), a frugivorous, Southeast Asian rainforest primate. Siamang groups affected by ENSO-related wildfires in a Sumatran rainforest were significantly smaller and experienced significantly lower infant and juvenile survival. Likelihood of infants surviving to subadults was higher by a factor of 2.8 for groups in undisturbed habitat. Burn groups had access to 48% fewer reproductive-size strangling fig trees in their territories, compared to non-burn groups. Dietary and foraging behaviour changes associated with habitat disturbance may result in lower productivity and higher mortality of young animals. Reproductive potential of burn groups is insufficient to offset low survival and groups are unlikely to persist for more than two generations. Increasing frequency of ENSO events increases the likelihood that siamang and other long-lived species that rely on fruiting trees will experience multiple fires within one generation; the resulting reduction in seed dispersal services will slow recovery of burned forest.