Seasonal, sexual, and individual variation in endurance and activity metabolism in lizards.

@article{Garland1987SeasonalSA,
  title={Seasonal, sexual, and individual variation in endurance and activity metabolism in lizards.},
  author={Theodore Garland and Paul L. Else},
  journal={The American journal of physiology},
  year={1987},
  volume={252 3 Pt 2},
  pages={
          R439-49
        }
}
Amphibolurus nuchalis were collected in central Australia during mid- (January) and late summer (March). Endurance time at 1 km/h on a motorized treadmill is greater in larger lizards, scaling as M0.65. Maximal O2 consumption (VO2max) scales as M0.96; standard metabolic rate (SMR) scales as M0.83. Factorial aerobic scope thus increases ontogenetically (9.4 at 1 g vs. 15 at 50 g). All organ masses scale allometrically; larger lizards have relatively smaller livers, but larger hearts and thigh… Expand
Effects of endurance training and captivity on activity metabolism of lizards.
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It is concluded that the adaptive response to endurance training, typical of mammals, does not generally occur in lizards, and levels of chronic activity that would elicit adaptive responses in mammals may be excessive for lizards and may induce pathological effects in joints and skeletal muscle. Expand
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Among species of lizards, helodermatids, varanids and skinks (which are mainly active foragers) have relatively high maximal aerobic capacity during forced exercise, whereas viviparous species have relatively low V̇O2,max. Expand
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Aerobic Performance in Belding's Ground Squirrels (Spermophilus beldingi): Variance, Ontogeny, and the Aerobic Capacity Model of Endothermy
TLDR
Results provide limited support for the aerobic capacity model for the evolution of endothermy in Belding's ground squirrels and find higher than expected intraspecific mass exponents for both V̇o2mr and V̧o2max. Expand
Metabolic rate and endurance capacity in Australian varanid lizards
In ecomorphological and ecophysiological studies, locomotor performance is often considered to be an intermediate step between the form of an organism and its environment. We examined this premise byExpand
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TLDR
It is concluded that the adaptive response to endurance training, typical of mammals, does not generally occur in lizards, and levels of chronic activity that would elicit adaptive responses in mammals may be excessive for lizards and may induce pathological effects in joints and skeletal muscle. Expand
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