Evolution of homeothermy in mammals.
We propose that mammalian homeothermy was was acquired in two steps. The first step enabled mammals to invade a nocturnal niche without an increase in resting metabolic rate. The second step enabled them to invade a diurnal niche and involved the acquisition of higher body temperatures and metabolic rates.
D000818:Animals; D001481:Basal Metabolism; D005075:Biological Evolution; D001833:Body Temperature Regulation; D004734:Energy Metabolism; D006706:Homeostasis; D008322:Mammals / Q000378:metabolism / Q000502:physiology*; D010101:Oxygen Consumption; D005082:Physical Exertion