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Lanna Cheng - One of the best experts on this subject based on the ideXlab platform.
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skaters of the seas comparative ecology of nearshore and pelagic halobates species hemiptera gerridae with special reference to japanese species
Marine Biology Research, 2012Co-Authors: Terumi Ikawa, Hidehiko Okabe, Lanna ChengAbstract:Abstract The insects overwhelm all other organisms of the world in species numbers and diversity. However, there are relatively few insects that inhabit the sea. Most of them are confined to the intertidal zone, with only five species of sea skaters, genus Halobates, having been successful in colonizing the open ocean. We discuss the ecology of both coastal and pelagic Halobates and the closely related genus Asclepios, focusing on their distribution ranges and adaptive strategies to marine environments accompanied by brief discussions of their biology. Updated information on the known localities for three species of Asclepios and some 40 coastal species of Halobates are presented. Many species live in vulnerable coastal habitats exposed to environmental pollution and coastal development. As a case study we trace the historical changes in populations of three Japanese sea skaters, Asclepios shiranui, Halobates matsumurai and H. japonicus, all designated as endangered species. For oceanic Halobates, we pres...
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the sea skater halobates heteroptera gerridae probable cause for extinction in the mediterranean and potential for re colonisation following climate change
Aquatic Insects, 2012Co-Authors: Lanna Cheng, Jakob Damgaard, Romain GarrousteAbstract:Sea-skaters in the genus Halobates Eschscholtz 1822 include some of the most specialised water striders and are found in tropical and subtropical seas around the world. Even though species of Halobates occur in both the Atlantic Ocean and the Red Sea, no extant sea-skater has been reported from the Mediterranean Sea. A fossil, Halobates ruffoi Andersen et al., 1994, described from Middle–Upper Eocene (45 Ma) Italy indicates that sea skaters were present in this part of the world in the past. Other geological evidence points to dramatic changes in the Mediterranean Sea during the Tertiary and Quaternary that may have led to their later extinction. In this paper we review briefly the distribution, systematics, evolution and ecology of Halobates, and discuss the potential for the Mediterranean to be recolonised following expected environmental changes due to global warming.
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occurrence and density of halobates micans hemiptera gerridae in the eastern south indian ocean
Entomological Science, 2007Co-Authors: Terumi Ikawa, Hidehiko Okabe, Shinobu Onodera, Sugihiko Hoshizaki, Lanna ChengAbstract:Author(s): Ikawa, Terumi; Onodera, Shinobu; Okabe, Hidehiko; Hoshizaki, Sugihiko; Cheng, Lanna | Abstract: Two species of ocean skaters, Halobates germanus and Halobates micans, live in the tropical and subtropicalwaters of the Indian Ocean. From December 1992 to December 1993, Halobates was intensively sampledin the easternmost region of the South Indian Ocean (13–18.5°S, 114–121E°), from which there have been a small number of records of Halobates. No H. germanus was caught, but a total of 1190 H. micans were collected, with densities estimated at 13 900–28 100 individuals/km2. This suggests that H. micans lives in the study area at high densities comparable to those in the Atlantic and the Pacific Oceans. We also discuss the possible effects of ocean currents and winds on the geographic distributions of the two Halobates speciesin the eastern South Indian Ocean.
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distribution of the oceanic insects halobates hemiptera gerridae off the south coast of japan
Entomological Science, 2004Co-Authors: Terumi Ikawa, Hidehiko Okabe, Sugihiko Hoshizaki, Takahiro Kamikado, Lanna ChengAbstract:Specimens of ocean skaters Halobates were collected off the south coast of Japan in the East China Sea in 1995, and from the Kumano-nada Sea to the East China Sea in 1998 and 1999. Three species were identified: H. micans, H. germanus and H. sericeus. We found two species co-occurring in comparable densities in different years, a phenomenon not hitherto reported in other regions of the ocean. We discuss distributions of the three Halobates species with special reference to the influence of the Kuroshio Current, temporal variations of sea-surface temperature, and monsoonal winds.
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the marine insect halobates heteroptera gerridae biology adaptations distribution and phylogeny
Oceanography and Marine Biology, 2004Co-Authors: Nils Moller Andersen, Lanna ChengAbstract:Among the million or so insect species known, only a few thousand are found in marine habitats. The genus Halobates is almost exclusively marine and is unique in having the only known species to live in the open ocean. Of the 46 Halobates species described, only five are completely oceanic in habitat, with the majority of species living in coastal areas associated with mangroves or other marine plants. This review presents a brief historical account of the genus and provides information on various aspects of its life history, ecology, special adaptations, distribution, and biogeography. Distribution maps of the five oceanic species as well as several of the more widely distributed coastal species have been updated. The phylogeny and evolution of Halobates based on morphology and recent molecular data are also discussed. A key to all known species of Halobates and related genera and a checklist of all species and their distributions are included as appendices.
Ulrich H Reichard - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE Open Access
2016Co-Authors: Esther Clarke, Ulrich H Reichard, Klaus ZuberbühlerAbstract:Context-specific close-range “hoo ” calls in wild gibbons (Hylobates lar) Esther Clarke1,2*, Ulrich H Reichard3 and Klaus Zuberbühler2,4 Background: Close range calls are produced by many animals during intra-specific interactions, such as during home range defence, playing, begging for food, and directing others. In this study, we investigated the most common close range vocalisation of lar gibbons (Hylobates lar), the ‘hoo ’ call. Gibbons and siamangs (family Hylobatidae) are known for their conspicuous and elaborate songs, while quieter, close range vocalisations have received almost no empirical attention, perhaps due to the difficult observation conditions in their natural forest habitats. Results: We found that ‘hoo ’ calls were emitted by both sexes in a variety of contexts, including feeding, separation from group members, encountering predators, interacting with neighbours, or as part of duet songs by the mated pair. Acoustic analyses revealed that ‘hoo ’ calls varied in a number of spectral parameters as a function of the different contexts. Males ’ and females ’ ‘hoo ’ calls showed similar variation in these context-specific parameter differences, although there were also consistent sex differences in frequency across contexts. Conclusions: Our study provides evidence that lar gibbons are able to generate significant, context-dependen
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lar gibbon Hylobates lar great call reveals individual caller identity
American Journal of Primatology, 2015Co-Authors: Thomas A Terleph, Suchinda Malaivijitnond, Ulrich H ReichardAbstract:Gibbons (family Hylobatidae) produce loud, elaborate vocalizations (songs), often in well-coordinated male/female duets. The female's great call, the most conspicuous phrase of the gibbon vocal repertoire, functions primarily to mediate territorial defense. Despite the fact that lar gibbons (Hylobates lar) are the most widely distributed and well researched hylobatid species and produce a rich vocal repertoire, the individual-specificity of their great calls has not previously been quantified. In addition, spectral and temporal features of notes occurring at specific locations within the lar great call have not been described. Here we provide such a description, and test the hypothesis that great calls are statistically discriminable between a large sample of individual callers. We compared recordings of great calls from 14 wild lar females in Khao Yai National Park, Thailand. Our analyses of principal components derived from spectral and temporal measures, as well as spectrograms from the entire great call, indicate that acoustic variation is sufficient to allow identification of individual callers (83.5% discriminability based on principal components, and inter-individual call variation exceeding intra-individual variation in overall spectrogram). These vocalizations potentially allow individual recognition of animals.
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Context-specific close-range “hoo” calls in wild gibbons (Hylobates lar)
BMC Evolutionary Biology, 2015Co-Authors: Esther Clarke, Ulrich H Reichard, Klaus ZuberbühlerAbstract:Background Close range calls are produced by many animals during intra-specific interactions, such as during home range defence, playing, begging for food, and directing others. In this study, we investigated the most common close range vocalisation of lar gibbons ( Hylobates lar ), the ‘hoo’ call. Gibbons and siamangs (family Hylobatidae) are known for their conspicuous and elaborate songs, while quieter, close range vocalisations have received almost no empirical attention, perhaps due to the difficult observation conditions in their natural forest habitats. Results We found that ‘hoo’ calls were emitted by both sexes in a variety of contexts, including feeding, separation from group members, encountering predators, interacting with neighbours, or as part of duet songs by the mated pair. Acoustic analyses revealed that ‘hoo’ calls varied in a number of spectral parameters as a function of the different contexts. Males’ and females’ ‘hoo’ calls showed similar variation in these context-specific parameter differences, although there were also consistent sex differences in frequency across contexts. Conclusions Our study provides evidence that lar gibbons are able to generate significant, context-dependent acoustic variation within their main social call, which potentially allows recipients to make inferences about the external events experienced by the caller. Communicating about different events by producing subtle acoustic variation within some call types appears to be a general feature of primate communication, which can increase the expressive power of vocal signals within the constraints of limited vocal tract flexibility that is typical for all non-human primates. In this sense, this study is of direct relevance for the on-going debate about the nature and origins of vocally-based referential communication and the evolution of human speech.
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The anti-predator behaviour of wild white-handed gibbons (Hylobates lar)
Behavioral Ecology and Sociobiology, 2012Co-Authors: Esther Clarke, Ulrich H Reichard, Klaus ZuberbühlerAbstract:Predation on gibbons is rarely observed in the wild. However, the gibbons' moderate body size and relatively small social groups suggest high vulnerability to predation. To assess the role of predation and to study their anti-predator behaviour, we presented visual predator models to nine groups of wild white-handed gibbons at Khao Yai National Park, Thailand. We measured subjects' immediate and delayed responses to four potential predators: tiger, clouded leopard, crested serpent eagle and reticulated python. Subjects reliably approached all four predators. In response to tigers and leopards, they additionally produced predator-specific songs and defecated copiously. In terms of delayed responses, distance between mated adults decreased, but only after exposure to the tiger model. In response to eagles and pythons, gibbons consistently vocalised, but this did not always include predator singing, and we found no long-term effects in overall activity or strata use. However, during 6 of 26 predator encounters, the gibbons produced songs with a structure that was intermediate between a duet song and a predator song more than 20 min after the predator encounter, indicating a long-term effect on their vocal behaviour. This study demonstrates that gibbons discriminate between different potential predators and respond to them with adaptive anti-predator behaviour, which include predator-specific vocal responses. We conclude that gibbons are not immune to predation and that terrestrial predators elicit consistent immediate and delayed anti-predation responses.
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Sleeping sites, sleeping places, and presleep behavior of gibbons (Hylobates lar)
American journal of primatology, 1998Co-Authors: Ulrich H ReichardAbstract:The sleeping habits of wild white-handed gibbons (Hylobates lar) were investigated to assess the risk of predation and predation-avoidance behavior. Sleeping sites were distributed throughout home ranges, including areas where they overlapped with neighbors, and appeared to be selected independently of habitat characteristics. Individuals did not build night nests or otherwise manipulate the vegetation around the sleeping place but slept on open branches. Group members usually slept in separate trees, and, except for females with infants, they never shared a sleeping place. Sleeping trees were entered several hours before dusk and were used for about 14-17 h. The majority of sleeping trees were used only once, and fewer were selected repeatedly by the same or other group members. Usually females with infants went into a sleeping tree first, then juveniles, and last were mostly subadult and adult males. Intragroup competition over access to a sleeping place was observed once. Average time difference between the first and last group member to enter a sleeping tree was 13 min. The sequence of departure from sleeping trees was more variable. Gibbon sleeping habits seem to primarily reflect adaptations to minimize predation risk. The predation-risk hypothesis was indirectly supported by observations of mobbing pythons, alarm calls given in response to birdes of prey flying low over the canopy, and more importantly by 1) the predominant use of large sleeping trees, which were among the tallest trees available, particularly by adult females with small infants and juveniles, 2) an unpredictable long-term pattern of reuse of sleeping places, and 3) inconspicuous presleep behavior.
David J Green - One of the best experts on this subject based on the ideXlab platform.
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scapular shape of extant hominoids and the african ape modern human last common ancestor
Journal of Human Evolution, 2016Co-Authors: David J Green, Ted A Spiewak, Brielle C Seitelman, Philipp GunzAbstract: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.
Debbie Guatellisteinberg - One of the best experts on this subject based on the ideXlab platform.
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sex differences in anthropoid mandibular canine lateral enamel formation
American Journal of Physical Anthropology, 2009Co-Authors: Debbie Guatellisteinberg, Rebecca J Ferrell, J E Spence, Tiffany Talabere, Amelia R Hubbard, Stacey SchmidtAbstract:Previous research has demonstrated that great ape and macaque males achieve large canine crown sizes primarily through extended canine growth periods. Recent work has suggested, however, that platyrrhine males may achieve larger canine sizes by accelerating rather than prolonging growth. This study tested the hypothesis that the ontogenetic pathway leading to canine sexual dimorphism in catarrhines differs from that of platyrrhines. To test this hypothesis, males and females of several catarrhine genera (Hylobates, Papio, Macaca, Cercopithecus, and Cercocebus) and three platyrrhine genera (Cebus, Ateles, and Callicebus) were compared in the number and spacing of perikymata (enamel growth increments) on their canine crowns. In addition, perikymata periodicities (the number of days of growth perikymata represent) were determined for five genera (Hylobates, Papio, Macaca, Cebus, and Ateles) using previously published as well as original data gathered for this study. The central findings are as follows: 1) males have more perikymata than females for seven of eight genera (in five of the seven, the differences are statistically significant); 2) in general, the greater the degree of sexual dimorphism, the greater the sex difference in male and female perikymata numbers; 3) there is no evidence of a systematic sex difference in primate periodicities; and 4) there is some evidence that sex differences in enamel formation rates may make a minor contribution to canine sexual dimorphism in Papio and Cercopithecus. These findings strongly suggest that in both catarrhines and platyrrhines prolongation of male canine growth is the primary mechanism by which canine crown sexual dimorphism is achieved.
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linear enamel hypoplasia in gibbons Hylobates lar carpenteri
American Journal of Physical Anthropology, 2000Co-Authors: Debbie GuatellisteinbergAbstract:This study describes the expression of linear enamel hypoplasia (LEH), a sensitive dental indicator of physiological stress, in Thailand gibbons (Hylobates lar carpenteri). Previous studies of enamel hypoplasia in hominoids have focused on great apes, with little attention given to the expression of this stress indicator in gibbons. In that gibbons differ from both monkeys and great apes in numerous life history features, LEH expression in gibbons might be expected to show significant differences from both. In this study, 92 gibbon specimens from two sites in Thailand were compared with several samples of monkeys and great apes in their expression of LEH. The intertooth distribution of LEH in gibbons was compared to that of chimpanzees and rhesus monkeys. Gibbon populations from both sites exhibit LEH frequencies intermediate between those of the monkey samples, in which LEH prevalence is usually low, and those of the great ape samples, in which LEH prevalence is high. Gibbons differ significantly from monkeys, but not great apes, in the number of individuals whose teeth record multiple stress events. Multiple episodes of stress are rarely recorded in the teeth of monkeys, while multiple stress events occur with higher frequency in gibbons and great apes. Taxonomic variation in the duration of crown formation, the prominence and spacing of perikymata on dental crowns, life history features, and/or experience of physiological stress may explain these patterns. The intertooth distribution of LEH in gibbons is, for different reasons, unlike that of either chimpanzees or rhesus monkeys. The mandibular canines of gibbons have significantly more LEH than any of their other teeth. Aspects of crown morphology, perikymata prominence/spacing, enamel thickness, and crown formation spans are potential causes of taxonomic variation in the intertooth distribution of LEH.
Klaus Zuberbühler - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE Open Access
2016Co-Authors: Esther Clarke, Ulrich H Reichard, Klaus ZuberbühlerAbstract:Context-specific close-range “hoo ” calls in wild gibbons (Hylobates lar) Esther Clarke1,2*, Ulrich H Reichard3 and Klaus Zuberbühler2,4 Background: Close range calls are produced by many animals during intra-specific interactions, such as during home range defence, playing, begging for food, and directing others. In this study, we investigated the most common close range vocalisation of lar gibbons (Hylobates lar), the ‘hoo ’ call. Gibbons and siamangs (family Hylobatidae) are known for their conspicuous and elaborate songs, while quieter, close range vocalisations have received almost no empirical attention, perhaps due to the difficult observation conditions in their natural forest habitats. Results: We found that ‘hoo ’ calls were emitted by both sexes in a variety of contexts, including feeding, separation from group members, encountering predators, interacting with neighbours, or as part of duet songs by the mated pair. Acoustic analyses revealed that ‘hoo ’ calls varied in a number of spectral parameters as a function of the different contexts. Males ’ and females ’ ‘hoo ’ calls showed similar variation in these context-specific parameter differences, although there were also consistent sex differences in frequency across contexts. Conclusions: Our study provides evidence that lar gibbons are able to generate significant, context-dependen
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Context-specific close-range “hoo” calls in wild gibbons (Hylobates lar)
BMC Evolutionary Biology, 2015Co-Authors: Esther Clarke, Ulrich H Reichard, Klaus ZuberbühlerAbstract:Background Close range calls are produced by many animals during intra-specific interactions, such as during home range defence, playing, begging for food, and directing others. In this study, we investigated the most common close range vocalisation of lar gibbons ( Hylobates lar ), the ‘hoo’ call. Gibbons and siamangs (family Hylobatidae) are known for their conspicuous and elaborate songs, while quieter, close range vocalisations have received almost no empirical attention, perhaps due to the difficult observation conditions in their natural forest habitats. Results We found that ‘hoo’ calls were emitted by both sexes in a variety of contexts, including feeding, separation from group members, encountering predators, interacting with neighbours, or as part of duet songs by the mated pair. Acoustic analyses revealed that ‘hoo’ calls varied in a number of spectral parameters as a function of the different contexts. Males’ and females’ ‘hoo’ calls showed similar variation in these context-specific parameter differences, although there were also consistent sex differences in frequency across contexts. Conclusions Our study provides evidence that lar gibbons are able to generate significant, context-dependent acoustic variation within their main social call, which potentially allows recipients to make inferences about the external events experienced by the caller. Communicating about different events by producing subtle acoustic variation within some call types appears to be a general feature of primate communication, which can increase the expressive power of vocal signals within the constraints of limited vocal tract flexibility that is typical for all non-human primates. In this sense, this study is of direct relevance for the on-going debate about the nature and origins of vocally-based referential communication and the evolution of human speech.
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The anti-predator behaviour of wild white-handed gibbons (Hylobates lar)
Behavioral Ecology and Sociobiology, 2012Co-Authors: Esther Clarke, Ulrich H Reichard, Klaus ZuberbühlerAbstract:Predation on gibbons is rarely observed in the wild. However, the gibbons' moderate body size and relatively small social groups suggest high vulnerability to predation. To assess the role of predation and to study their anti-predator behaviour, we presented visual predator models to nine groups of wild white-handed gibbons at Khao Yai National Park, Thailand. We measured subjects' immediate and delayed responses to four potential predators: tiger, clouded leopard, crested serpent eagle and reticulated python. Subjects reliably approached all four predators. In response to tigers and leopards, they additionally produced predator-specific songs and defecated copiously. In terms of delayed responses, distance between mated adults decreased, but only after exposure to the tiger model. In response to eagles and pythons, gibbons consistently vocalised, but this did not always include predator singing, and we found no long-term effects in overall activity or strata use. However, during 6 of 26 predator encounters, the gibbons produced songs with a structure that was intermediate between a duet song and a predator song more than 20 min after the predator encounter, indicating a long-term effect on their vocal behaviour. This study demonstrates that gibbons discriminate between different potential predators and respond to them with adaptive anti-predator behaviour, which include predator-specific vocal responses. We conclude that gibbons are not immune to predation and that terrestrial predators elicit consistent immediate and delayed anti-predation responses.