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Marcus Vinicius Vieira - One of the best experts on this subject based on the ideXlab platform.
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Positional behaviour and tail use by the bare-tailed woolly opossum Caluromys Philander (Didelphimorphia, Didelphidae)
Mammalian Biology, 2012Co-Authors: Matheus Fernandes Dalloz, Diogo Loretto, Bernardo Papi, Priscilla Cobra, Marcus Vinicius VieiraAbstract:We present the first quantitative description of postural behaviour of a free ranging metatherian, the bare-tailed woolly opossum, Caluromys Philander . Postural behaviour was observed using 10 camera traps set in front of artificial nests, located in the understory of an Atlantic forest site in Rio de Janeiro, Brazil. Seven locomotory and positional modes were identified, with a predominance of diagonal couplets. Individuals used three types of grasp as observed in captivity, but the frequency of digital grasping was higher in the wild. The tail was used as an additional grasping limb, preventing falls and freeing hands to other activities, but the tail was also used to carry leaves for nest building. The use of camera traps may represent a breakthrough in the study of positional behaviours in the wild.
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homing behavior of Philander frenatus didelphimorphia didelphidae across a fragmented landscape in the atlantic forest of brazil
Mastozoología neotropical, 2009Co-Authors: Jayme Augusto Prevedello, Ana Claudia Delciellos, Marcus Vinicius VieiraAbstract:We report the first record of homing behavior of a Neotropical marsupial, the opossum Philander frenatus. The individual studied returned to the home forest fragment where it was captured (1050 m away) crossing a hostile matrix, instead moving to a much closer fragment (50 m distant). Movements did not follow wind or the direction of the closest fragment, but they were significantly oriented towards the home fragment. The individual probably had previous experience with the release site. This unique observation suggests that the ability of P. frenatus to overcome the effects of habitat fragmentation may be higher than considered previously. RESUMO: Comportamento de "homing" de Philander frenatus (Didelphimorphia, Didelphidae) em uma paisagem fragmentada da Mata Atlântica do Brasil. Relatamos o primeiro registro de comportamento de "homing" de um marsupial neotropical, Philander frenatus. O individuo estudado retornou para o fragmento onde foi capturado (distante 1050 m) atravessando uma matriz hostil, ao inves de se deslocar para um fragmento muito mais proximo (distante 50 m). Os movimentos nao seguiram a direcao do vento ou do fragmento mais proximo, sendo significativamente orientados para o fragmento de captura. O individuo provavelmente tinha experiencia previa com o local de soltura. Este registro sugere que a habilidade de P. frenatus de tolerar os efeitos da fragmentacao de habitat pode ser maior do que considerada previamente.
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modelos ecomorfologicos para vertebrados arboricolas o caso do marsupial Philander frenata
Holos Environment, 2002Co-Authors: Ana Claudia Delciellos, Marcus Vinicius VieiraAbstract:Performance measurements can be used to infer the fundamental niche of species, allowing predictions of habitat or resource use in the absence of species interactions. We propose a standard set of tests to measure locomotory performance of arboreal vertebrates, and a procedure to develop ecomorphological models based on performance tests and path analysis. The proposed tests simulate habitat features such as support diameter and incline. Models of relationships between variables can be formulated, compared with path analysis, and the model of best fit chosen. This procedure was applied to the didelphid marsupial Philander frenata, comparing the effect of body shape on stride length and frequency in arboreal walking. The model including paths to stride length and frequency had a significant better fit than the model with paths only to stride length. An a posteriori model - obtained from the elimination of nonsignificant paths – suggested that the relative length of claws and tail were the more determinant of stride frequency, whereas stride length was more affected by the relative length of the limbs. These are hypotheses about an important aspect of the fundamental niche of didelphid marsupials, allowing inferences of niche similarity based on morphology. Independent data are necessary to test these hypotheses.
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body size and form in two neotropical marsupials didelphis aurita and Philander opossum marsupialia didelphidae
Mammalia, 1997Co-Authors: Marcus Vinicius VieiraAbstract:Les marsupiaux neotropicaux des genres Didelphis et Philander ont une taille differente, mais on montre ici qu'ils ont aussi des differences de la forme du corps. Les mensurations externes ont ete prises sur des adultes de D. aurita et P. opossum. La taille a ete mesuree comme composante principale d'une matrice d'un pool de covariance. La forme du corps a ete comparee par une analyse multivariee de covariance. La taille a ete la covariable pour les mensurations tete et corps et queue et celles des elements du membre. La longueur du pied a ete la covariable pour sa largeur et la longueur des griffes du pied. En tenant compte de la difference de taille, D. aurita a une queue relativement plus courte mais le pied est plus large, et le bras, l'avant-bras et les griffes du pied sont plus longues. Ces differences de forme du corps peuvent etre reliees a l'accroissement de la taille chez Didelphis et ses consequences pour la locomotion terrestre et aboricole.
D. Julien‐laferrière - One of the best experts on this subject based on the ideXlab platform.
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Foraging strategies and food partitioning in the neotropical frugivorous mammals Caluromys Philander and Potos flavus
Journal of Zoology, 1999Co-Authors: D. Julien‐laferrièreAbstract:The bare-tailed woolly opossum, Caluromys Philander , and the kinkajou, Potos flavus , are two syntopic neotropical nocturnal, arboreal and frugivorous mammals. Because of close ecology but great difference in size (weight 300 vs 3000 g), they represent pertinent models to examine the influence of size on foraging strategy. These species were studied by radio-tracking and direct observation during 22 months in a tropical forest in French Guiana. Both mammals’ foraging strategies with regard to flowers and fruits are characterized as follows: (1) numerous plant families and species are exploited; (2) most plant species are selected according to their abundance; (3) diet selectivity and diversity are similar in both mammals; (4) relative parts of flowers and fruits in the diet vary according to their year-long availability; (5) the choice of fruiting species is not related to the morphological type, size, or nutritious quality of fruits but instead depends on easy access to the edible part; (6) the length of foraging bouts is correlated with production for the most frequently exploited tree species; (7) feeding bouts are shorter in P. flavus than in C. Philander ; (8) P. flavus exploits large, highly productive canopy trees, while C. Philander also visits canopy trees with low production and understorey trees. In conclusion, both mammals are opportunistic flower- and fruit-eaters, but the larger species ( P. flavus ) exploits larger, more scattered food patches, while the smaller one ( C. Philander ) also exploits smaller, more numerous and more evenly distributed food patches.
P Charlesdominique - One of the best experts on this subject based on the ideXlab platform.
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nitrogen requirements of the didelphid marsupial caluromys Philander
Journal of Comparative Physiology B-biochemical Systemic and Environmental Physiology, 2000Co-Authors: William J Foley, P Charlesdominique, D JulienlaferriereAbstract:The use of fruit-based diets by a small arboreal marsupial, the woolly opossum (Caluromys Philander) was studied to elucidate the mechanisms used to compensate for a low dietary protein concentration. The passage of a liquid phase digesta marker (Cr-EDTA) through the gut was significantly faster when animals were fed a diet containing 0.45% N compared to that measured on a diet containing 0.90% N. The size of the gut of the two groups was similar except that the caecum of animals fed 0.45% N was significantly larger than in those animals fed 0.90% N. Animals fed a diet of 0.45% N ate significantly more food than those fed higher levels of nitrogen but there was no significant difference in the dry matter digestibility of the diet. The maintenance nitrogen requirement of the animals was 176 mg dietary N or 146 mg truly digestible nitrogen per kg metabolic body mass, with low losses of non-dietary faecal nitrogen being notable. There was no significant difference between diets in any measured parameter of urea metabolism and all animals recycled between 60% and 80% of the endogenously synthesised urea.
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dominance relationships in captive male bare tailed woolly opossum caluromys Philander marsupialia didelphidae
Revue d'écologie, 2000Co-Authors: M L Guillemin, M Atramentowicz, P CharlesdominiqueAbstract:In this study, we test the hypothesis that body size is a key factor in determining dominance relationships during agonistic encounters between captive males Caluromys Philander, and male-male competition was experimentally tested. Physiological and behavioural parameters were investigated during 18 experimental trials including two males alone (6), and two males with a female (12). A dominance-submission relationship exists even with no female, although competition is stronger when a female is present. Dominance is based on age and body mass in C. Philander under experimental conditions. When dominance was settled, dominance rank was clear cut and consistent during all the experimentation. Stable dominance-subordination relationships may benefit both dominants and subordinates by minimizing the incidence of serious wounds. Males show typical signs of social stress: both body weight and hematocrit rate decrease, but subordinates are more stressed than dominants. Dominant males exhibit a lower decrease in hematocrit rate and a higher decrease in testosterone concentration in blood. They display most of the "aggressive" behaviours, scan more actively the experimental cages and engage in fewer aggressive interactions with females in comparison with subordinate males
Ben S Mbarek - One of the best experts on this subject based on the ideXlab platform.
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male influence on oestrous cycles in female woolly opossum caluromys Philander
Reproduction, 1991Co-Authors: M Perret, Ben S MbarekAbstract:Plasma progesterone concentrations and the occurrence of oestrous cycles were studied in isolated woolly opossums subsequently subjected to male influences during a 40-day period. Pairing (N = 48) or exposure to male urine (N = 15) resulted in all females exhibiting oestrous during the stimulation phase, providing evidence that the activation of ovarian activity in the woolly opossum involves pheromonal cues from males. The latency of occurrence of oestrous in stimulated females depended upon their sexual state before male stimulation. In anoestrous females, the mean latency was 20.7 +/- 0.9 days (N = 35), a value which agrees with the duration of the follicular phase. In females which first entered oestrous before male stimulation, the latency of induced oestrous was inversely correlated to the date of occurrence of the previous oestrous. The inter-oestrous interval was normal (38.1 +/- 1 days, N = 5) when females were in oestrous at the beginning of male stimulation. In contrast, the inter-oestrous interval was significantly shortened (28.7 +/- 2 days, N = 7) or lengthened (51.1 +/- 1.7 days, N = 16) depending on whether females were in the luteal or follicular phases at the beginning of male stimulation. During pairing several females became pregnant and gave birth 24 +/- 0.9 days (N = 13) after copulation. In the woolly opossum, the response to male influences involves mechanisms similar to those observed in eutherians and results in enhancement and synchronization of oestrous cycles in females. Pheromonal interactions could play an important role in synchronizing oestrous cycles in wild females during the dry season, a period when animals regroup to feed on spatially localized food resources.
Ricardo Bassinisilva - One of the best experts on this subject based on the ideXlab platform.
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contribution to the taxonomy and host relations of the genus serratacarus trombidiformes trombiculidae
Journal of Medical Entomology, 2021Co-Authors: Fernando De Castro Jacinavicius, Darci Moraes Barrosbattesti, Ricardo Bassinisilva, Cal Welbourn, Ron Ochoa, Matheus HuangbastosAbstract:The genus SerratacarusGoff and Whitaker 1984, currently includes only two species, Serratacarus dietzi Goff and Whitaker, 1994 and Serratacarus lasiurus Goff and Whitaker, 1994, which were recorded on cricetid rodents from natural reserve areas of Brazil. Here, we provide a review of the morphological characters for both species and synonymize of the species Trombewingia brasiliensisGoff and Gettinger, 1991 with S. lasiurus. Additionally, we provide new locality records for both species and the first record for S. dietzi on southeastern four-eyed opossum, Philander frenatus Olfers, 1818 (Didelphimorphia, Didelphidae).