Temperature preference in geckos: Diel variation in juveniles and adults

Field studies of nocturnal geckos have revealed that many species actively thermoregulate during both the day and the night. Data from laboratory stud ies indicate that geckos prefer body temperatures greater than those experi enced during activity in the field, but data on diel patterns of temperatur e preference are inconsistent. We measured preferred body temperature (T-p) of five species of geckos (Coleonyx mitratus, Eublepharis macularis, Hemid actylus turcicus, Ocdura marmorata, and O. reticulata) to determine the ext ent of within-day and between-day variation. Additionally, we compared T(p) s of juveniles and adults of O. marmorata and E. macularis. Preferred days. Juveniles and adults had similar T(p)s at all time periods. We hypothesize that a preference for higher T(b)s toward the end of photophase initiates the thermoregulatory behavior observed in field-active geckos, and facilita tes higher body temperatures during activity in early scotophase.