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Actividad y termorregulacion estival de Podarcis pityusensis BOSCA, 1883 (Saura: Lacertidae) en Ibiza y Formentera



Abstract. The behavioral thermoregulation of P. pityusensis was studied for a period of one week during August, 1980. The cloacal temperatures and the ground and air temperatures were recorded by means of thermistors. P. pityusensis behaves like a heliotermic species with a temperature range between 28.5 and 41.5 ° C. Very significant correlations were found to exist between the Tc (Body temperatures) and the Ta (Air temperatures) or between the Tc and the Ts (Ground temperatures) in all ofthe specimens analyzed.
There are also significant statistical differences between te mean Tc in individuals during thermoregulation and  the Tc of individuals active on the ground or inactive underneath stones. The daily pattern of activity is bimodal; the variations in body temperatures, being as a whole relatively independent of the fluctuations in the ambient temperature, adjust themselves to this pattern. P. pityusensis, roughly speaking, manifest several characteristics of the behavioral thermoregulation and pattern of activity similar to those described for other lizards such as Psammodromos algirus, inhabitants of the mediterranean region which is characterized by its hot, dry summers

V Perez Mellado, A Salvador /1981) - Amphibia-Reptilia 2
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