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Jorge Morales - One of the best experts on this subject based on the ideXlab platform.
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Anatomy of the “false thumb” of Tremarctos ornatus (Carnivora, Ursidae, Tremarctinae) : phylogenetic and functional implications
Estudios Geológicos, 2006Co-Authors: Manuel J. Salesa, Plinio Montoya, Gema Siliceo, Mauricio Antón, Juan Abella, Jorge MoralesAbstract:We describe for the first time the radial sesamoid or “false thumb” of the spectacled bear (Tremarctos ornatus), showing its great morphological similarities with that of the giant panda (Ailuropoda melanoleuca) and the differences with that of the rest of the Ursidae. This points to the existence of a common origin for this structure in both species, but considering the accepted phylogenies of ursids, the sharing of a “false thumb” in T. ornatus and A. melanoleuca would be a plesiomorphy for these groups, whereas in the rest of the ursids the radial sesamoid was probably reduced, lacking the specialised function that this bone has in Tremarctinae and Ailuropodinae.
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Indarctos (Ursidae, Mammalia) from the Spanish Turolian (Upper Miocene)
Scripta Geologica, 2001Co-Authors: Plinio Montoya, Luis Alcalá, Jorge MoralesAbstract:Abundant fossils of the bear Indarctos atticus (Weithofer, 1888) from the Lower Turolian (MN11) site of Crevillente 2 (Alicante, Spain) and some new material from the Middle Turolian (MN12) of Concud and Valdecebro 5 (Teruel, Spain) are described. On the other hand some dental remains from Crevillente 2 are identified as Indarctos sp. cf. I. vireti Villalta & Crusafont, 1943 on the basis of their small size. The status of different Indarctos species are discussed.
Plinio Montoya - One of the best experts on this subject based on the ideXlab platform.
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paracamelichnum jumillensis n ichnogen n ichnosp upper miocene camelidae ichnites from the hoya de la sima site murcia spain
Ichnos-an International Journal for Plant and Animal Traces, 2009Co-Authors: Felix Perezlorente, Cayetano Herrero, Emilio Herrero, Plinio MontoyaAbstract:In the proximity of Jumilla (Murcia, Spain) there is a site called Hoya de la Sima with mammal footprints dating from the Upper Miocene. This site is an old gypsum quarry where footprints of Hipparion, Pecoripeda, Carnivora, Ursidae, and Proboscidea were discovered. While the site was being cleaned and conditioned after the discovery to protect the prints, Camelidae and other prints were unearthed and are currently being studied. The description of the Camelidae ichnites demonstrates that these belong to a new ichnogenera, produced by the prints of Paracamelus. The grouping of trackways is congruent with the gregariousness of these animals and with the concentration observed in similar sites.
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Anatomy of the “false thumb” of Tremarctos ornatus (Carnivora, Ursidae, Tremarctinae) : phylogenetic and functional implications
Estudios Geológicos, 2006Co-Authors: Manuel J. Salesa, Plinio Montoya, Gema Siliceo, Mauricio Antón, Juan Abella, Jorge MoralesAbstract:We describe for the first time the radial sesamoid or “false thumb” of the spectacled bear (Tremarctos ornatus), showing its great morphological similarities with that of the giant panda (Ailuropoda melanoleuca) and the differences with that of the rest of the Ursidae. This points to the existence of a common origin for this structure in both species, but considering the accepted phylogenies of ursids, the sharing of a “false thumb” in T. ornatus and A. melanoleuca would be a plesiomorphy for these groups, whereas in the rest of the ursids the radial sesamoid was probably reduced, lacking the specialised function that this bone has in Tremarctinae and Ailuropodinae.
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Indarctos (Ursidae, Mammalia) from the Spanish Turolian (Upper Miocene)
Scripta Geologica, 2001Co-Authors: Plinio Montoya, Luis Alcalá, Jorge MoralesAbstract:Abundant fossils of the bear Indarctos atticus (Weithofer, 1888) from the Lower Turolian (MN11) site of Crevillente 2 (Alicante, Spain) and some new material from the Middle Turolian (MN12) of Concud and Valdecebro 5 (Teruel, Spain) are described. On the other hand some dental remains from Crevillente 2 are identified as Indarctos sp. cf. I. vireti Villalta & Crusafont, 1943 on the basis of their small size. The status of different Indarctos species are discussed.
Sen Zhao - One of the best experts on this subject based on the ideXlab platform.
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genomic analysis of expressed sequence tags in american black bear ursus americanus
BMC Genomics, 2010Co-Authors: Chunxuan Shao, Anna V Goropashnaya, Nathan C Stewart, Oivind Toien, Brian M Barnes, Sen Zhao, Yichi Xu, Vadim B FedorovAbstract:Background Species of the bear family (Ursidae) are important organisms for research in molecular evolution, comparative physiology and conservation biology, but relatively little genetic sequence information is available for this group. Here we report the development and analyses of the first large scale Expressed Sequence Tag (EST) resource for the American black bear (Ursus americanus).
Arnaudo, María Eugenia - One of the best experts on this subject based on the ideXlab platform.
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Análisis morfológico de la región auditiva de los Ursidae Tremarctinae, su aplicación en sistemática filogenética y paleobiología
2017Co-Authors: Arnaudo, María EugeniaAbstract:Este trabajo de Tesis Doctoral tuvo por objetivo estudiar en forma comparada la morfología de la región auditiva de los Tremarctinae Ursidae, a fin de describir caracteres de importancia sistemático-filogenética e interpretar la anatomía de esta región enfrentándola con los distintos hábitos de vida de los taxones actuales. En ese contexto se estudió la región auditiva y el basicráneo de las especies actuales y extintas de Tremarctinae, excepto: Plionarctos, ya que no se conocen ni cráneos ni regiones auditivas separadas hasta el momento y A. simus y A. wingei, debido a que no se pudo obtener TACs de estas especies. También se describió y estudió la región auditiva y el basicráneo en otras especies de la familia Ursidae (Ursus arctos, U. maritimus, U. americanus, U. malayanus, U. spelaeus, U. thibetanus y Ailuropoda melanoleuca) que fueron utilizadas para realizar comparaciones. Las descripciones se realizaron por medio de la observación directa (en el caso del basicráneo) y a través de las TACs (para estudiar el oído medio e interno). Para evaluar la señal filogenética presente en el basicráneo de los Ursidae se realizó un estudio de disparidad morfológica mediante Morfometría Geométrica (MG), cuyo resultado fue analizado en el contexto filogenético del grupo.The aim of this thesis was to make a comparative study of the auditory region morphology of Tremactinae Ursidae in order to describe features with systematicphylogenetic importance and to interpret the anatomy of this region in relation to different lifestyles of living taxa. In this context, the auditory region and basicranium of extant and extinct Tremactinae were studied except for the genus Plionarctos as no skulls or auditory regions are known, and A. simus and A. wingei as the CT scans of the specimens were unsuccessful. Members of Ursinae subfamliy (Ursus arctos, U. maritimus, U. americanus, U. malayanus, U. spelaeus, U. thibetanus and Ailuropoda melanoleuca) were studied to make comparisons. Descriptions were made through direct observations (for the basicranium) and using CT scans (for the middle and inner ear). A disparity analysis using geometric morphometrics (GM) was made to test the presence of phylogenetic signal in the basicranium of Ursidae. The results were analyzed in the phylogenetic context of the group. For the GM the following taxa were analyzed: 11 specimens of Ailuropodinae, 23 of Tremactinae and 131 of Ursinae. The specimens were photographed in ventral view where 22 Landmarks (LM) of type 1 and 2 were used and analysed with the software MorphoJ 1.05f (Klingenberg, 2011). This analysis was completed performing a phylo-morphospace. For this purpose, a super-tree was made using molecular (of extant species) and morphological information (of extinct species). Different studies were made to analyze the relationship between size and shape of the Ursidae middle and inner ear with respect to the lifestyles (e.g. locomotor agility).Facultad de Ciencias Naturales y Muse
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Geometric morphometric analysis of the Basicranium of Ursidae (Carnivora, Mammalia)
Sociedad de Ciencias Morfológicas de La Plata, 2017Co-Authors: Fernandez Blanco, María Victoria, Arnaudo, María EugeniaAbstract:Presentamos el primer estudio del basicráneo de Ursidae utilizando un estudio de morfometría geométrica en dos dimensiones. Se seleccionaron 22 landmarks con homologías de tipo I y II. Se digitalizaron con el tpsUtil y tpsdig2. Los análisis se hicieron con MorphoJ. Para analizar la variación de forma se realizó un análisis de componentes principales y una regresión de las coordenadas de landmarks alineadas contra el logaritmo en base 10 del tamaño del centroide. La máxima variación morfológica se resume en los 2 primeros componentes principales (CP). A lo largo del CP1 se observa una separación entre la subfamila Ailuropodinae con respecto a la subfamila Tremarctinae y Usinae. Estas últimas se encuentran próximas en el morfoespacio. Las especies fósiles (Arctotherium angustidens, A. vetustum, A. tarijense y A. simus) tienen basicráneos más cortos y mastoides más expandidos que los ursinos actuales pero basicráneos más largos y mastoides más comprimidos lateralmente que los ailuropodinos. A lo largo del CP2 no se detecta una clara separación entre especies. De acuerdo con los resultados obtenidos, se propone que la variación de forma del basicráneo en Ursidae estaría explicada por la historia filogenética entre las especies. Palabras clave: Ursidae, morfometría geométrica, basicráneo.We present the first study of the auditory region and basicranium of Ursidae using a two-dimensional geometric morphometric analysis. Twenty-two type I and II landmarks were established and digitized using tpsUtil and tpsdig2. MorphoJ was used for the analysis. Shape variation was analyzed using a principal component analysis and a regression of the landmark coordinates against the logarithm of centroid size. The highest variation is summarized in the first two principal components (PC). Along PC1 the Ailuropodinae were separated with respect to the Tremarctinae and Ursinae. The latter were close to each other in the morphospace. The extinct species (Arctotherium angustidens, A. vetustum, A. tarijense and A. simus) present a shorter basicranium and more expanded mastoids than extant ursins but longer basicranium and more laterally compressed mastoids than ailuropodins. There was no clear separation of species along PC2. According to these results, we propose that the shape variation of the basicranium in Ursidae could be explained by the phylogenetic history within species. Keywords: Ursidae, geometric morphometric, basicranium
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Estudio morfogeométrico del Basicráneo de Ursidae (Carnivora, Mammalia)
'Universidad Nacional de La Plata', 2016Co-Authors: Arnaudo, María Eugenia, Fernandez Blanco, María VictoriaAbstract:Presentamos el primer estudio del basicráneo de Ursidae utilizando un estudio de morfometría geométrica en dos dimensiones. Se seleccionaron 22 landmarks con homologías de tipo I y II. Se digitalizaron con el tpsUtil y tpsdig2. Los análisis se hicieron con MorphoJ. Para analizar la variación de forma se realizó un análisis de componentes principales y una regresión de las coordenadas de landmarks alineadas contra el logaritmo en base 10 del tamaño del centroide. La máxima variación morfológica se resume en los 2 primeros componentes principales (CP). A lo largo del CP1 se observa una separación entre la subfamila Ailuropodinae con respecto a la subfamila Tremarctinae y Usinae. Estas últimas se encuentran próximas en el morfoespacio. Las especies fósiles (Arctotherium angustidens, A. vetustum, A. tarijense y A. simus) tienen basicráneos más cortos y mastoides más expandidos que los ursinos actuales pero basicráneos más largos y mastoides más comprimidos lateralmente que los ailuropodinos. A lo largo del CP2 no se detecta una clara separación entre especies. De acuerdo con los resultados obtenidos, se propone que la variación de forma del basicráneo en Ursidae estaría explicada por la historia filogenética entre las especies.We present the first study of the auditory region and basicranium of Ursidae using a two-dimensional geometric morphometric analysis. Twenty-two type I and II landmarks were established and digitized using tpsUtil and tpsdig2. MorphoJ was used for the analysis. Shape variation was analyzed using a principal component analysis and a regression of the landmark coordinates against the logarithm of centroid size. The highest variation is summarized in the first 2 principal components (PC). Along PC1 the Ailuropodinae were separated with respect to the Tremarctinae and Ursinae. The latter were close to each other in the morphospace. The extinct species (Arctotherium angustidens, A. vetustum, A. tarijense and A. simus) present a shorter basicranium and more expanded mastoids than extant ursins but longer basicranium and more laterally compressed mastoids than ailuropodins. There was no clear separation of species along PC2. According to these results, we propose that the shape variation of the basicranium in Ursidae could be explained by the phylogenetic history within species.Fil: Arnaudo, Maria Eugenia. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fernandez Blanco, María Victoria. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Kaare Magne Nielsen - One of the best experts on this subject based on the ideXlab platform.
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Terrestrial Vertebrate Animal Metagenomics, Non-domesticated Ursidae, Bears
2014Co-Authors: Monica A. Sundset, Trine Glad, Kaare Magne NielsenAbstract:Bears are terrestrial mammals belonging to the family Ursidae (order: Carnivora) that appear in a wide variety of habitats in North and South America, Asia, and Europe. Terrestrial animals live predominantly or entirely on land, as opposed to aquatic animals which live predominantly or entirely in water. The term may also be used to describe animals that live primarily on the ground, while arboreal species on the other hand live primarily in trees. Most studies of the gut metagenomics of mammals have been conducted on domestic or captive individuals fed artificial diets. Only limited data are available from non-domesticated mammalian species, such as bears, living in their natural habitats. Non-domesticated animals are wild, free-living animals eating their natural diet, not domesticated by humans or kept in a zoo. Most of the metagenomic studies of the microbiota in the digestive tracts of bears have focused on fecal samples and are reviewed below. Metagenomics may also be referred to as environmental genomics, ecogenomics, or community genomics. While traditional microbial genome sequencing relies upon cultivation of single clones, early environmental microbial DNA analysis focused on sequencing of specific, cloned genes to produce a profile of diversity in a natural sample. Such DNA analysis has revealed that the majority of microbial biodiversity in environmental samples has been previously missed by cultivation-based techniques. Recent studies using “shotgun” Sanger sequencing or massively parallel pyrosequencing produces largely unbiased samples of all genes from all the members of the sampled communities. There are eight extant species of bears: Asian black bear (Selenarctos thibetanus), black bear (Ursus americanus), brown bear (Ursus arctos), giant panda (Ailuropoda melanoleuca), polar bear (Ursus maritimus), sloth bear (Melursus ursinus), spectacled bear (Tremarctos ornatus), and sun bear (Helarctos malayanus). The polar bear is mostly carnivorous, while the giant panda feeds almost entirely on bamboo. The remaining six species are omnivorous animals eating both plant and animal materials. Studies of fecal samples from humans and 59 other mammalian species including brown bears and giant panda, kept captive in zoos, suggest that both host diet and host phylogeny influence the bacterial diversity of their digestive system, with increasing diversity from carnivory to herbivory (Ley et al. 2008a, b).
