Which one among the following animal groups can regulate their body temperatures regardless of their environment ?

Animals are broadly categorized based on their thermoregulation capabilities into endotherms and ectotherms.

• Endotherms (Warm-blooded): These animals can maintain a nearly constant internal body temperature through metabolic heat production, regardless of the external environment. Mammals and birds are the primary groups of endotherms.
• Ectotherms (Cold-blooded): These animals, including reptiles, amphibians, and fish, lack internal physiological mechanisms to regulate temperature. Their body temperature fluctuates according to the temperature of their surroundings.

Because mammals and birds possess high metabolic rates and insulating structures (like fur, fat, or feathers), they are the only groups listed that can regulate their body temperature independently of environmental changes.