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Regulation

as during extreme winters, drought, or in When the environmental temperature rises,
arid regions, this high energy demand can the body gains heat from the surroundings.
make survival difficult. Consequently, the rate of metabolism
increases and the animal becomes
Another disadvantage is their susceptibility active. However, prolonged exposure to
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to overheating, particularly in hot high temperatures may lead to death of
environments. To regulate their body the animal due to overheating. In order
temperature, endotherms must expend to avoid this, ectothems move to cooler
energy in cooling mechanisms like areas or hibernate in burrows and nests.
sweating or panting. In extremely hot Most adjustment of body temperature in
conditions, these processes can lead to ectotherms are by behavioural means which
dehydration, further challenging their include sun basking, huddling, hibernation,
survival. Additionally, energy-intensive aestivation, migration, and burrowing.
thermoregulation mechanisms, such as
shivering to generate heat in cold conditions Sun basking: Ectothermic animals may use
or sweating to dissipate heat in warmer radiant heat from the environment to warm
climates, place a significant strain on an their bodies. Sun basking is a common
endotherm’s metabolic resources, hence means of warming up using sun rays.
increasing their overall energy demands. Reptiles and some amphibians bask in the
sun with their bodies spread out to increase

Temperature regulation in ectotherms the surface area for heat absorption. When
Ectotherms, in contrast to endotherms, it is too hot, they hide in the shade or in
water bodies to allow their bodies to cool.
do not have physiological mechanisms
to regulate their body temperature. When Hibernation and migration: During
the environmental temperature falls, their winter some animals undergo a period of
bodies lose heat to the environment. This long deep sleep. This state of dormancy
results into a fall in their body temperature. is called hibernation. Hibernation is a
Under such conditions, their rate of state where an animal greatly reduces its
metabolic reactions becomes low and metabolic activities and slows the heart
the animal becomes inactive. Ectotherms rate for the purpose of conserving energy.
are thus faced with a problem of being This enables the animals to survive in cold
overcooled if they are subjected to low condition without consuming much energy.
temperatures. They overcome this problem During this time, the metabolic rate can
by either moving away from cold areas be reduced by 20-98%. As a result, the
or by hibernating. Animals whose body animal reduces food and oxygen utilisation.
temperature varies with temperature of their Animals with no suitable insulators such
surroundings because they cannot regulate as fur or fat cannot hibernate. They avoid
their body temperature internally are called extreme low temperature by migrating to
poikilotherms.
warmer places.

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