Question: Which is a poikilothermic animal? (NSCL 2018)
Options:
Lion
Parrot
Bat
Wall lizard
🔑Key Points:
• Cold-blooded animals:
-Cold-blooded animals are animals that are not capable of regulating their body’s temperature according to the temperature of the surrounding.
-They do not have a constant body temperature.
-Cold-blooded animals include reptiles, amphibians, fishes, insects, and other invertebrates.
-These animals are also called poikilothermic animals.
• Warm-blooded animals:
-Warm-blooded animals are the animals that are capable of maintaining a nearly constant body temperature irrespective of the temperature of the environment.
-Their body temperature remains the same as they move from one surrounding to another.
-The temperature control is mostly obtained by regulating their metabolic rates.
-Warm-blooded animals include birds and mammals.
-These animals are also called homeothermic animals.
• Shark:
-Sharks don’t fit the criteria for mammals in the most important respects.
-They don’t produce milk, they don’t have hair, and most of them are cold-blooded.
-The only characteristic they share with mammals is that some shark species give live birth.
-They belong to the class Chondrichthyes and not Mammalia.
• ​Whale:
-Whale belongs to the class Mammalia.
-The whale is a mammal, not a fish, hence it is warm-blooded.
-It is classified under the Phylum Chordata.
-Whales give birth to live offspring (whereas fish hatch their young from eggs), and feed their young (called calves) on milk produced by the female's own body.Â