Seasonal Changes in Daily Metabolic Patterns of Tegu Lizards (Tupinambis merianae) Placed in the Cold (17°C) and Dark

Abstract

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Metabolic Flexibility: Hibernation, Torpor, and Estivation

“…This whole-animal response corresponds to seasonal decreases in tissue protein synthesis that are extremely temperature sensitive (Q 10 from 6 to 21) during the transition from autumn to winter (176). Among terrestrial ectotherms, the large South American tegu lizard Tupinambis merianae shows a substantial drop in standard MR during the winter, most of which is independent of changes in T a and T b (196). The wood frog (Lithobates sylvatica) is a well-studied vertebrate ectotherm that overwinters.…”

Daily and seasonal rhythms in the respiratory sensitivity of red-eared sliders (Trachemys scripta elegans)

“…Removal of all environmental cues typically reduces the amplitude of daily rhythms, until the rhythms are lost altogether (Aschoff et al, 1982;Kenagy and Vleck, 1982;Underwood, 1992;Tosini et al, 2001). Tegu lizards have also been shown to lose circadian oscillations in metabolism over time (Milsom et al, 2008). There was large variability in the response of these lizards to constant darkness, with some individuals losing the rhythms after a day in constant darkness and others maintaining the rhythms up to 14 days.…”

The relationship between body temperature, heart rate, breathing rate, and rate of oxygen consumption, in the tegu lizard (Tupinambis merianae) at various levels of activity

“…The black and white tegu lizard (Tupinambis merianae) has been the focus of several metabolic studies, including the metabolic responses to exercise and feeding (Skovgaard and Wang 2004;Klein et al 2006), the metabolic effects of changes in age, body size and season , metabolic acclimation at constant temperature and photoperiod across seasons (Abe 1995;Milsom et al 2008), and metabolic depression during seasonal dormancy (Abe 1983(Abe , 1995Andrade and Abe 1999;de Souza et al 2004). The most important factors influencing metabolic rate during dormancy in lizards in the field are reductions in temperature and activity.…”