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Geraldine Veron - One of the best experts on this subject based on the ideXlab platform.
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Molecular systematics and biogeography of the Hemigalinae Civets (Mammalia, Carnivora)
European journal of taxonomy, 2017Co-Authors: Geraldine Veron, Céline Bonillo, Alexandre Hassanin, Andrew P. JenningsAbstract:Due to the difficulty in obtaining samples, the systematics of the Hemigalinae Civets has not been fully resolved. The aim of this study was to clarify the relationships of the species and the intraspecific diversity within this subfamily, and to explore the environmental factors that might have affected its evolution. Using two mitochondrial and two nuclear markers, we confirmed that the Hemigalinae comprises Owston’s Civet, the otter Civet, Hose’s Civet and the banded Civet, but also the Sulawesi palm Civet (formerly included in the Paradoxurinae). Our study showed that the banded and Owston’s Civets are sister species, and suggested that Hose’s Civet is sister to these two. Within the banded Civet, we observed a high divergence between individuals from the Mentawai Islands and those from Sumatra and Borneo (while the latter two were not strongly divergent), likely due to the deep sea channel between the Mentawai Islands and Sumatra. Unexpectedly, the Sumatran and Peninsular Malaysian individuals were not closely related, despite the fact that these two regions have repeatedly been connected during the last glaciations. No high polymorphism was found within Owston’s Civet, although three groups were obtained: southern China, northern Vietnam and central Vietnam, which might be related to Pleistocene climatic fluctuations.
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molecular systematics of the small toothed palm Civet arctogalidia trivirgata reveals a strong divergence of bornean populations
Mammalian Biology, 2015Co-Authors: Geraldine Veron, Marie-lilith Patou, Andrew P. JenningsAbstract:Abstract The small-toothed palm Civet Arctogalidia trivirgata is a small, arboreal Civet belonging to the subfamily Paradoxurinae (Viverridae) that is found in northeast India, southern China, and Southeast Asia. This is an understudied species with a debated taxonomy. Variation in coat colour and pattern has driven authors to describe numerous taxa of this Civet species, but no recent taxonomic revision and no intraspecific molecular study have been conducted. We sequenced three mitochondrial and one nuclear markers in order to study the geographical genetic structure of the small-toothed palm Civet and to evaluate the genetic divergence between different populations, and we examined various morphological features. Our molecular results showed that the small-toothed palm Civet forms two divergent clades: Clade 1: mainland Southeast Asia, Sumatra and nearby small islands, and Java; and Clade 2: Borneo. Further investigations are needed to verify the possible specific status of these two clades. The populations north of the Isthmus of Kra are characterized by a white ear tip and form a separate clade from the populations south of the Isthmus of Kra, but their genetic divergence does not warrant a specific status. The Javan small-toothed palm Civet was found to have a low genetic divergence to the nearby populations within Clade 1. Further studies are needed in order to confirm these results and to revise the taxonomy of the small-toothed palm Civet.
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Diversity and occupancy of small carnivores within oil palm plantations in central Sumatra, Indonesia
Journal of mammalian ova research, 2015Co-Authors: Andrew P. Jennings, Andreas Dwi Advento, Sudharto Ps, Jean-pierre Caliman, Mohd Naim, Anak Agung Ketut Aryawan, Aude Verwilghen, Geraldine VeronAbstract:In Southeast Asia, the conversion of native forests to oil palm plantations threatens tropical biodiversity, but very little is known about the impacts of oil palm cultivation on small carnivore species. To determine the diversity and occupancy of small carnivores within oil palm plantations and to investigate possible factors that might affect their presence within oil palm, we used camera-traps within two oil palm plantations in central Sumatra, analysed the data using occupancy modelling and tested whether two covariates (distance to the edge of the oil palm habitat and distance from extensive areas of lowland forest) affected the model parameters for each small carnivore species. From 3164 camera-trap days, we detected only three small carnivores: leopard cat (Prionailurus bengalensis), common palm Civet (Paradoxurus hermaphroditus) and Malay Civet (Viverra tangalunga), which indicates that there was a low diversity of small carnivores within the oil palm plantations. Both the leopard cat and common palm Civet were found deep within the oil palm, whereas the Malay Civet was only detected near the edge in one of the plantations. The leopard cat and common palm Civet had very high occupancy values, whereas the Malay Civet had low values for both occupancy and detection probability. Neither covariate affected occupancy of the leopard cat and common palm Civet, but distance from the edge of the oil palm habitat did influence their detection probabilities. Malay Civet occupancy decreased with distance from the oil palm edge, and detection probability was affected by distance from extensive areas of lowland forest. Forests and rest/den site availability are suggested to be important features for small carnivores with oil palm-dominated landscapes.
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predicted distributions and conservation status of two threatened southeast asian small carnivores the banded Civet and hose s Civet
Mammalia, 2013Co-Authors: Andrew P. Jennings, Jedediah F Brodie, Anthony J Giordano, John Mathai, Geraldine VeronAbstract:Knowledge of the distribution and habitat preferences of a species is of paramount importance when assessing its conservation status. We used accurately recorded occurrence records and ecological niche modelling to predict the distribution of two threatened and poorly known small carnivore species that occur in Southeast Asia, the banded Civet (Hemigalus derbyanus) and Hose's Civet (Diplogale hosei), and analysed their spatial niche differentiation for habitat and elevation. We then identified possible anthropogenic threats, and used our modelling predictions to recommend surveying priorities. The predicted distribution of the banded Civet was principally in lowland evergreen forest in southern Myanmar/Thailand, Peninsular Malaysia, Sumatra, Borneo and three Mentawai Islands (Siberut, Sipora and South Pagai), and for Hose's Civet in evergreen forest across the higher elevation regions of Borneo. Our niche analyses suggested that there is a tendency for these two species to separate spatially along an elevation gradient: the banded Civet is mainly found in lowland areas, whereas Hose's Civet primarily occurs at higher elevations. Our study strongly indicated that these two viverrids are forest-dependent species that may be threatened by forest loss, degradation and fragmentation. Field surveys should be prioritised in areas where each species is predicted to occur and no records currently exist.
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predicted distributions and ecological niches of 8 Civet and mongoose species in southeast asia
Journal of Mammalogy, 2011Co-Authors: Andrew P. Jennings, Geraldine VeronAbstract:Abstract Although Southeast Asia has a high diversity of small carnivore species, little is known about their distributions and ecology, and several species are now threatened with extinction. We predicted the distributions of 8 Civet and mongoose species within Southeast Asia using ecological niche modeling, determined their habitat/elevation niche preferences, examined the interspecific differences in these 2 niche parameters, and investigated possible factors that could have affected these distribution and niche patterns. We found a tendency for each Civet and mongoose species to separate spatially from related species on geographical, habitat, and elevation gradients, and that 3 pairs of Civet and mongoose species showed similar distribution patterns and habitat/elevation preferences. The large Indian Civet (Viverra zibetha) and crab-eating mongoose (Herpestes urva) have similar distributions throughout mainland Southeast Asia, are found over a broad range of elevations, and occur primarily in evergre...
Andrew P. Jennings - One of the best experts on this subject based on the ideXlab platform.
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Molecular systematics and biogeography of the Hemigalinae Civets (Mammalia, Carnivora)
European journal of taxonomy, 2017Co-Authors: Geraldine Veron, Céline Bonillo, Alexandre Hassanin, Andrew P. JenningsAbstract:Due to the difficulty in obtaining samples, the systematics of the Hemigalinae Civets has not been fully resolved. The aim of this study was to clarify the relationships of the species and the intraspecific diversity within this subfamily, and to explore the environmental factors that might have affected its evolution. Using two mitochondrial and two nuclear markers, we confirmed that the Hemigalinae comprises Owston’s Civet, the otter Civet, Hose’s Civet and the banded Civet, but also the Sulawesi palm Civet (formerly included in the Paradoxurinae). Our study showed that the banded and Owston’s Civets are sister species, and suggested that Hose’s Civet is sister to these two. Within the banded Civet, we observed a high divergence between individuals from the Mentawai Islands and those from Sumatra and Borneo (while the latter two were not strongly divergent), likely due to the deep sea channel between the Mentawai Islands and Sumatra. Unexpectedly, the Sumatran and Peninsular Malaysian individuals were not closely related, despite the fact that these two regions have repeatedly been connected during the last glaciations. No high polymorphism was found within Owston’s Civet, although three groups were obtained: southern China, northern Vietnam and central Vietnam, which might be related to Pleistocene climatic fluctuations.
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molecular systematics of the small toothed palm Civet arctogalidia trivirgata reveals a strong divergence of bornean populations
Mammalian Biology, 2015Co-Authors: Geraldine Veron, Marie-lilith Patou, Andrew P. JenningsAbstract:Abstract The small-toothed palm Civet Arctogalidia trivirgata is a small, arboreal Civet belonging to the subfamily Paradoxurinae (Viverridae) that is found in northeast India, southern China, and Southeast Asia. This is an understudied species with a debated taxonomy. Variation in coat colour and pattern has driven authors to describe numerous taxa of this Civet species, but no recent taxonomic revision and no intraspecific molecular study have been conducted. We sequenced three mitochondrial and one nuclear markers in order to study the geographical genetic structure of the small-toothed palm Civet and to evaluate the genetic divergence between different populations, and we examined various morphological features. Our molecular results showed that the small-toothed palm Civet forms two divergent clades: Clade 1: mainland Southeast Asia, Sumatra and nearby small islands, and Java; and Clade 2: Borneo. Further investigations are needed to verify the possible specific status of these two clades. The populations north of the Isthmus of Kra are characterized by a white ear tip and form a separate clade from the populations south of the Isthmus of Kra, but their genetic divergence does not warrant a specific status. The Javan small-toothed palm Civet was found to have a low genetic divergence to the nearby populations within Clade 1. Further studies are needed in order to confirm these results and to revise the taxonomy of the small-toothed palm Civet.
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Diversity and occupancy of small carnivores within oil palm plantations in central Sumatra, Indonesia
Journal of mammalian ova research, 2015Co-Authors: Andrew P. Jennings, Andreas Dwi Advento, Sudharto Ps, Jean-pierre Caliman, Mohd Naim, Anak Agung Ketut Aryawan, Aude Verwilghen, Geraldine VeronAbstract:In Southeast Asia, the conversion of native forests to oil palm plantations threatens tropical biodiversity, but very little is known about the impacts of oil palm cultivation on small carnivore species. To determine the diversity and occupancy of small carnivores within oil palm plantations and to investigate possible factors that might affect their presence within oil palm, we used camera-traps within two oil palm plantations in central Sumatra, analysed the data using occupancy modelling and tested whether two covariates (distance to the edge of the oil palm habitat and distance from extensive areas of lowland forest) affected the model parameters for each small carnivore species. From 3164 camera-trap days, we detected only three small carnivores: leopard cat (Prionailurus bengalensis), common palm Civet (Paradoxurus hermaphroditus) and Malay Civet (Viverra tangalunga), which indicates that there was a low diversity of small carnivores within the oil palm plantations. Both the leopard cat and common palm Civet were found deep within the oil palm, whereas the Malay Civet was only detected near the edge in one of the plantations. The leopard cat and common palm Civet had very high occupancy values, whereas the Malay Civet had low values for both occupancy and detection probability. Neither covariate affected occupancy of the leopard cat and common palm Civet, but distance from the edge of the oil palm habitat did influence their detection probabilities. Malay Civet occupancy decreased with distance from the oil palm edge, and detection probability was affected by distance from extensive areas of lowland forest. Forests and rest/den site availability are suggested to be important features for small carnivores with oil palm-dominated landscapes.
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predicted distributions and conservation status of two threatened southeast asian small carnivores the banded Civet and hose s Civet
Mammalia, 2013Co-Authors: Andrew P. Jennings, Jedediah F Brodie, Anthony J Giordano, John Mathai, Geraldine VeronAbstract:Knowledge of the distribution and habitat preferences of a species is of paramount importance when assessing its conservation status. We used accurately recorded occurrence records and ecological niche modelling to predict the distribution of two threatened and poorly known small carnivore species that occur in Southeast Asia, the banded Civet (Hemigalus derbyanus) and Hose's Civet (Diplogale hosei), and analysed their spatial niche differentiation for habitat and elevation. We then identified possible anthropogenic threats, and used our modelling predictions to recommend surveying priorities. The predicted distribution of the banded Civet was principally in lowland evergreen forest in southern Myanmar/Thailand, Peninsular Malaysia, Sumatra, Borneo and three Mentawai Islands (Siberut, Sipora and South Pagai), and for Hose's Civet in evergreen forest across the higher elevation regions of Borneo. Our niche analyses suggested that there is a tendency for these two species to separate spatially along an elevation gradient: the banded Civet is mainly found in lowland areas, whereas Hose's Civet primarily occurs at higher elevations. Our study strongly indicated that these two viverrids are forest-dependent species that may be threatened by forest loss, degradation and fragmentation. Field surveys should be prioritised in areas where each species is predicted to occur and no records currently exist.
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predicted distributions and ecological niches of 8 Civet and mongoose species in southeast asia
Journal of Mammalogy, 2011Co-Authors: Andrew P. Jennings, Geraldine VeronAbstract:Abstract Although Southeast Asia has a high diversity of small carnivore species, little is known about their distributions and ecology, and several species are now threatened with extinction. We predicted the distributions of 8 Civet and mongoose species within Southeast Asia using ecological niche modeling, determined their habitat/elevation niche preferences, examined the interspecific differences in these 2 niche parameters, and investigated possible factors that could have affected these distribution and niche patterns. We found a tendency for each Civet and mongoose species to separate spatially from related species on geographical, habitat, and elevation gradients, and that 3 pairs of Civet and mongoose species showed similar distribution patterns and habitat/elevation preferences. The large Indian Civet (Viverra zibetha) and crab-eating mongoose (Herpestes urva) have similar distributions throughout mainland Southeast Asia, are found over a broad range of elevations, and occur primarily in evergre...
Fang Li - One of the best experts on this subject based on the ideXlab platform.
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mechanisms of host receptor adaptation by severe acute respiratory syndrome coronavirus
Journal of Biological Chemistry, 2012Co-Authors: Kailang Wu, Matthew S Wilken, Guiqing Peng, Robert J. Geraghty, Fang LiAbstract:The severe acute respiratory syndrome coronavirus (SARS-CoV) from palm Civets has twice evolved the capacity to infect humans by gaining binding affinity for human receptor angiotensin-converting enzyme 2 (ACE2). Numerous mutations have been identified in the receptor-binding domain (RBD) of different SARS-CoV strains isolated from humans or Civets. Why these mutations were naturally selected or how SARS-CoV evolved to adapt to different host receptors has been poorly understood, presenting evolutionary and epidemic conundrums. In this study, we investigated the impact of these mutations on receptor recognition, an important determinant of SARS-CoV infection and pathogenesis. Using a combination of biochemical, functional, and crystallographic approaches, we elucidated the molecular and structural mechanisms of each of these naturally selected RBD mutations. These mutations either strengthen favorable interactions or reduce unfavorable interactions with two virus-binding hot spots on ACE2, and by doing so, they enhance viral interactions with either human (hACE2) or Civet (cACE2) ACE2. Therefore, these mutations were viral adaptations to either hACE2 or cACE2. To corroborate the above analysis, we designed and characterized two optimized RBDs. The human-optimized RBD contains all of the hACE2-adapted residues (Phe-442, Phe-472, Asn-479, Asp-480, and Thr-487) and possesses exceptionally high affinity for hACE2 but relative low affinity for cACE2. The Civet-optimized RBD contains all of the cACE2-adapted residues (Tyr-442, Pro-472, Arg-479, Gly-480, and Thr-487) and possesses exceptionally high affinity for cACE2 and also substantial affinity for hACE2. These results not only illustrate the detailed mechanisms of host receptor adaptation by SARS-CoV but also provide a molecular and structural basis for tracking future SARS-CoV evolution in animals.
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structural analysis of major species barriers between humans and palm Civets for severe acute respiratory syndrome coronavirus infections
Journal of Virology, 2008Co-Authors: Fang LiAbstract:It is believed that a novel coronavirus, severe acute respiratory syndrome coronavirus (SARS-CoV), was passed from palm Civets to humans and caused the epidemic of SARS in 2002 to 2003. The major species barriers between humans and Civets for SARS-CoV infections are the specific interactions between a defined receptor-binding domain (RBD) on a viral spike protein and its host receptor, angiotensin-converting enzyme 2 (ACE2). In this study a chimeric ACE2 bearing the critical N-terminal helix from Civet and the remaining peptidase domain from human was constructed, and it was shown that this construct has the same receptor activity as Civet ACE2. In addition, crystal structures of the chimeric ACE2 complexed with RBDs from various human and Civet SARS-CoV strains were determined. These structures, combined with a previously determined structure of human ACE2 complexed with the RBD from a human SARS-CoV strain, have revealed a structural basis for understanding the major species barriers between humans and Civets for SARS-CoV infections. They show that the major species barriers are determined by interactions between four ACE2 residues (residues 31, 35, 38, and 353) and two RBD residues (residues 479 and 487), that early Civet SARS-CoV isolates were prevented from infecting human cells due to imbalanced salt bridges at the hydrophobic virus/receptor interface, and that SARS-CoV has evolved to gain sustained infectivity for human cells by eliminating unfavorable free charges at the interface through stepwise mutations at positions 479 and 487. These results enhance our understanding of host adaptations and cross-species infections of SARS-CoV and other emerging animal viruses.
Jorns Fickel - One of the best experts on this subject based on the ideXlab platform.
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phylogenetic relationship of two threatened endemic viverrids from the sunda islands hose s Civet and sulawesi Civet
Journal of Zoology, 2012Co-Authors: Andreas Wilting, Jorns FickelAbstract:Although phylogenetic relationships among most genera and species in the mammalian family Viverridae have been analysed genetically, no molecular data exist for two threatened island-endemic species, Hose's Civet Diplogale hosei of Borneo and the Sulawesi Civet Macrogalidia musschenbroekii (both monospecific genera). We obtained the first DNA sequences (large parts of the mitochondrial cytochrome b and NADH2 genes) for these species, using museum specimens, and confirmed that both species warrant their own genus. Hose's Civet is a member of the subfamily Hemigalinae and is a sister taxon of the banded Civet Hemigalus derbyanus and Owston's Civet Chrotogale owstoni; but the relationship among these three species remained unresolved. The Sulawesi Civet does not belong to the subfamily Paradoxurinae, in which it is currently classified (hence its widely used English name Sulawesi palm Civet), but instead to the subfamily Hemigalinae. We recommend dropping ‘palm’ from all vernacular names of the Hemigalinae to distinguish the Hemigalinae from the ‘true’ palm Civets – the Paradoxurinae.
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evolutionary history of the paradoxurus palm Civets a new model for asian biogeography
Journal of Biogeography, 2010Co-Authors: Marie-lilith Patou, Andrew P. Jennings, Andreas Wilting, Jorns Fickel, Philippe Gaubert, Jacob A Esselstyn, Corinne Cruaud, Geraldine VeronAbstract:Aim Using molecular data and dental features, we investigated the genetic and morphological diversity among species of palm Civets in the genus Paradoxurus, with a focus on the common palm Civet, Paradoxurus hermaphroditus (Carnivora, Viverridae), in order to address biogeographic scenarios and provide recommendations for a taxonomic revision. Location Asia: Pakistan to the Lesser Sunda Islands. Methods We investigated the genetic diversity within Paradoxurus using two mitochondrial (cytochrome b, control region) and one nuclear (intron 7 of the β-fibrinogen) markers. We used samples from 85 individuals of P. hermaphroditus (including 20 museum specimens) and one representative of each of the other species in the genus Paradoxurus: Paradoxurus jerdoni and Paradoxurus zeylonensis. DNA sequences were analysed using phylogenetic and haplotype network methods, and divergence dates were estimated for the clades retrieved. Furthermore, we examined dental characters from a large series of specimens and compared the morphological variation with the molecular data. Results Our phylogenetic analyses revealed that P. hermaphroditus is paraphyletic. We identified three major lineages distributed: (1) in the Indian subcontinent, south China, Hainan and in areas above 200 m in Indochina; (2) in Peninsular Malaysia, Java, Sumatra and in areas below 200 m in Indochina; and (3) in Borneo, the Philippines and the Mentawai archipelago. Our morphological observations were congruent with these three molecular lineages. Divergence date estimates inferred a Pliocene origin for Paradoxurus (2.8–5.7 Ma), with the three main clades diversifying from the mid–Early Pliocene to the end of the Pliocene. We suggest that the flooding of the Isthmus of Kra during the Pliocene was a major event shaping the diversification of Paradoxurus palm Civets. We also hypothesize that the elevational segregation of the two lineages on the mainland could have resulted from the vegetational changes that were induced by Late Pliocene glacial episodes. Main conclusions The Isthmus of Kra is a major boundary between two major lineages of P. hermaphroditus. There is a need for a taxonomic revision for P. hermaphroditus, and we suggest that this species should be split into at least three species.
Alan Rabinowitz - One of the best experts on this subject based on the ideXlab platform.
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behaviour and movements of sympatric Civet species in huai kha khaeng wildlife sanctuary thailand
Journal of Zoology, 1991Co-Authors: Alan RabinowitzAbstract:Five individuals of four Civet species were captured and followed by radiotelemetry in a mosaic of dry tropical forest in Huai Kha Khaeng Wildlife Sanctuary, Thailand. Observations were made on a fifth, arboreal species which was never captured. Radio-collared Civets used overall areas ranging from 3.1 to 17 km2 with average monthly ranges from 0.72 to 5.4 km2. Average monthly ranges, home range centre shifts and activity radii showed a linear increase with weight and size of the individual, both within and between species. Despite individual differences, there were similar behavioural responses to extrinsic seasonal changes. Civets had activity levels of 50–55% and displayed nocturnal activity patterns. The four smallest Civets used trees as resting sites extensively while the largest Civet, Viuerra zibetha, was always located on the ground. Faecal analysis indicated that Civets fed on at least 18 fruiting tree species as well as rodents, insects and crabs. At least one of the fruits found in Civet faeces, Cassia fistula, was not eaten by other major frugivores in the area. The Civets showed a preference for mixed deciduous and dry evergreen forest over dry deciduous dipterocarp forest, which had a lower abundance of known food items. The role that Civets play as seed dispersal agents may help in the maintenance and structuring of tropical forest communities.