Data/hora: 02/06/2024 19:16:10

Provedor de dados: | 97
País: | Chile
Título: | Energetics, thermoregulation and torpor in the Chilean mouse-opossum Thylamys elegans (Didelphidae)
Autores: | Bozinovic,Francisco; RuÍz,Gricelda; CortÉs,Arturo; Rosenmann,Mario.
Data: | 2005-01-01
Ano: | 2005
Palavras-chave: | Chile; Marsupials; Energetic; Thermoregulation; Facultative torpor.
Resumo: | In this paper we studied the energetic expenditure and thermoregulation of the Chilean mouse-opossum Thylamys elegans (Dielphidae) a nocturnal small marsupial, endemic of southern South America. We studied their standard energetic and determined whether they exhibit shallow daily torpor or deep prolonged torpor as a function of ambient temperature and food availability. Thylamys elegans partially supports the hypothesis that Neotropical marsupials have somewhat a higher basal metabolic rate (BMR) and thermal conductance (Cm) than Australian ones. In fact, BMR was higher but Cm was lower than expected for their body mass. The higher mass-independent BMR of the Chilean mouse-opossum may be explained by its insectivorous food habits and its low Cm by its temperate habitats. Euthermic Chilean mouse-opossum showed daily fluctuations in body temperature being significantly higher during night time. In addition T. elegans entered in daily torpor and aroused spontaneously only was food was absent. That is, this species display a facultative type of daily torpor because propensity to enter in torpor was dependent of the combination of food absence and low ambient temperature. No torpor was observed when food was available. During torpor ambient temperature was slightly above ambient temperature between 0.3 to 0.5 °C. Torpor in this species as well as in marsupials in general, appears to be a flexible and an opportunistic response to unpredictable environmental conditions
Tipo: | Journal article
Idioma: | Inglês
Identificador: | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2005000200003
Editor: | Sociedad de Biología de Chile
Formato: | text/html
Fonte: | Revista chilena de historia natural  v.78 n.2 2005