Adaptation :
Every organism has natural capacity to adapt according to the surrounding environment. Hence, the organisms modify according to the specific environment and survive. Hence, all the modifications and peculiarities in the structure and physiology of an animal according to the environment is called as adaptation.
As a result of adaptation, the animal develops harmony with the environment. For example, in the aquatic animals the body becomes streamlined (boat shaped) to ease swimming. Similarity, the body of flyer animals is light and they have wings.
Desert adaptations :
The mam factors in the desert climates arc deficiency of water, extremes of temperature, dust storms & feeble vegetation. In the desert, the day temperature is very high and the night temperature is very low. Hence, the desert animals experience extremes of temperature twice in a day.
Such animals have efficient capacity to conserve water. Their skin is hygroscopic and covered by thick dermal scales. The desert animals exhibit following main adaptions –
- The body is covered by scales or spines to prevent water evaporation.
- They excrete uric acid to prevent water loss eg. reptiles.
- Camel can survive without drinking water in the desert for a long period. They have lots of different adaptations. For example, they have hump which store large fat and this fat provides metabolic water. Their RBC are oval rather than circular which makes them better at withstanding the osmotic changes when they are dehydrated. They may obtain moisture from plants they consume.
- The feet of camel are broad, flat and have leathery pads at the bottom to walk on the sand.
Aquatic adaptations :
Most of the animals on the earth are aquatic (both marine & fresh water). They are well adapted to their aquatic life. Some of the adaptations are as follows –
- Their body is streamlined or boat shaped to minimize friction during swimming.
- Fishes have lateral line system which is sensory to water pressure & water currents.
- Some fishes have air bladder which provides buoyancy in addition to assist respiration.
- They develops certain organs for swimming. For example in whale, the fore limbs modify to from flippers. The fishes have fins for swimming.
