IADIZA   20886
INSTITUTO ARGENTINO DE INVESTIGACIONES DE LAS ZONAS ARIDAS
Unidad Ejecutora - UE
artículos
Título:
Physiological diversity in tolerance to water deprivation among species of South American desert rodents
Autor/es:
BOZINOVIC, F., A. P. CRUZ-NETO, A. CORTÉS, G.B. DIAZ, R.A. OJEDA AND S. GIANNONI.
Revista:
JOURNAL OF ARID ENVIRONMENTS
Editorial:
ELSEVIER
Referencias:
Año: 2007 p. 427 - 442
ISSN:
0140-1963
Resumen:
Rodents from arid and semi-arid deserts are faced with the problem of water conservation. The
physiological responses of small rodents to such conditions have been intensively investigated over
broad geographically disjunct areas. Despite the presence of xeric habitats in South America since the
late Tertiary, some studies suggest that sigmodontine South-American desert rodents do not display
the same diversity of physiological responses at the species level as those observed in other desertdwelling
species of rodents. In this paper, we analyzed the physiological responses to water
deprivation, at the interespecific and interindividual level, among eight species of sigmodontine
desert-dwelling rodents from different geographical areas within South-American deserts. Using
randomization tests, we found no significant phylogenetic signal for resistance to water deprivation
or for individual variability in this response. Contrary to our initial predictions, we observed that
sigmodontine rodents from arid/semi-arid habitats (Monte Desert) had significantly lower rates of
body mass loss per day (higher tolerances to water deprivation) than species from the hyperarid
deserts. We showed that sigmodontine rodents from South America showed a remarkable diversity
of physiological mechanisms for coping with water shortage resulting from different evolutionary
adaptive strategies. This diversity, however, displays a rather unexpected pattern in terms of its
geographical distribution
physiological responses of small rodents to such conditions have been intensively investigated over
broad geographically disjunct areas. Despite the presence of xeric habitats in South America since the
late Tertiary, some studies suggest that sigmodontine South-American desert rodents do not display
the same diversity of physiological responses at the species level as those observed in other desertdwelling
species of rodents. In this paper, we analyzed the physiological responses to water
deprivation, at the interespecific and interindividual level, among eight species of sigmodontine
desert-dwelling rodents from different geographical areas within South-American deserts. Using
randomization tests, we found no significant phylogenetic signal for resistance to water deprivation
or for individual variability in this response. Contrary to our initial predictions, we observed that
sigmodontine rodents from arid/semi-arid habitats (Monte Desert) had significantly lower rates of
body mass loss per day (higher tolerances to water deprivation) than species from the hyperarid
deserts. We showed that sigmodontine rodents from South America showed a remarkable diversity
of physiological mechanisms for coping with water shortage resulting from different evolutionary
adaptive strategies. This diversity, however, displays a rather unexpected pattern in terms of its
geographical distribution