Distinguish between :
(a) Hibernation and aestivation:
(b) Ectotherms and endotherms.

Explanation

(a) Hibernation (Winter sleep) is the period of dormancy and reduced metabolic rate during winter months mostly foound in the poikilothermal animals like amphibians, lizards , snakes ,etc.
Aestivation (summer sleep) is the period of dormancy and reduced metabolic rate during summer months and is found in lung fish .
(b) Endotherms are homeothermal or warm-blooded animals which can keep their body temperature constant even in changing environmental tempeartures e.g. birds and mammals , while ectothersm and poikilothermal or cold-blooded animals are those whose body temperature changes with the change in enviornmental temperature e.g., fishes, amphibians and reptiles.