Basal MetabolismEnergy MetabolismCaloric RestrictionEnergy IntakeOxygen ConsumptionCalorimetry, IndirectBody WeightBody Temperature RegulationBody CompositionBody SizeMetabolismLongevityBody TemperatureDiet, ReducingFood LabelingObesityWater Loss, InsensibleTomography, Emission-ComputedGlucoseCarbon DioxideEatingDietary FatsOxygenBrainDeoxyglucoseDietThermogenesisFeeding BehaviorFluorodeoxyglucose F18HibernationDeoxy SugarsDietary CarbohydratesFlight, AnimalFast FoodsMenu PlanningAgingCerebrovascular CirculationDivingRestaurantsAcclimatizationFoodWeight LossAdipose TissuePhysical ExertionRestModels, BiologicalRespiratory TransportTemperatureBirdsDietary ProteinsEstivationBody ConstitutionMammalsCalorimetrySirtuinsReptilesExerciseFood DeprivationCold TemperatureOrgan SizeBlood GlucoseTime FactorsFluorine RadioisotopesSwimmingAnalysis of VarianceWeight GainFastingMuscle, SkeletalRespirationSpecies SpecificityLeptinNutritional RequirementsPhysiology, ComparativeInsulinAdaptation, PhysiologicalFood PreferencesCharadriiformesBoidaeHyperphagiaProtein-Energy MalnutritionDesert ClimateBody Mass IndexRegression AnalysisSirtuin 1Body WaterOxygen IsotopesFur SealsNutritional Physiological PhenomenaNitrogenLocusta migratoriaBody Surface AreaNutritive ValueMarsupialiaMotor ActivityLiverAppetiteAlligators and CrocodilesSeasonsCold ClimatePositron-Emission Tomography