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| Adaptation to Environment In Animals Contd… |
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| Volant Adaptations in Common Pigeon |
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| Adaptations for flight are called as volant adaptations. Bats, birds and insects are well adapted for an active flight. Some important flight adaptations are |
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 Boat or spindle shaped body that offers no resistance to air |
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 Forelimbs are modified into wings |
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 An exoskeleton of feathers which provide an insulation, thereby preventing the loss of heat and help maintain a constant body temperature. |
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 The short tail with tail feathers which serves as a rudder in steering and counter balance during perching. |
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 Presence of well developed flight muscles and a keeled sternum. |
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 Presence of hollow or pneumatic bones to make their body light. |
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 Presence of air sacs which serve as reservoirs of air and provide lightness and buoyancy to the body |
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 A large cerebellum which allows the bird to maintain equilibrium and co-ordination. |
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| These are the adaptations for running and are found in flightless birds such as ostrich, kiwi and many other animals. |
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 More or less stream lined body so as to offer minimum resistances to air during running |
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 Hind limbs are usually long and have claws. |
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 In the forelimbs ulna and in the hind limbs the fibula bones are greatly reduced as an adaptation for fast running. |
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| Animals which dig into burrows for shelter and food are called fossorial animals. They have adaptations for burrowing. |
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 Spindle shaped body to offer little resistance during going in and out of burrows. |
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 Small tapering head with snout for burrowing |
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 Eyesight is reduced as they are of no use in the dark |
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 External ears tend to disappear as they might be an obstruction in burrowing. |
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 Short and stout limbs are provided with strong claws for digging. |
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 They hibernate during winter or unfavourable conditions. |
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| These adaptations help the animals in climbing and are found in various animals like squirrels, lemurs, sloths and rodents. |
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| Arboreal Adaptations in Squirrel |
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 The limb girdles are very stout giving support to the body in climbing. |
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 Well developed claws help in grasping and climbing |
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 Syndactyly or union of digits is seen in some animals. |
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| Example: Chameleon |
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| Chameleon Adaptation for Arboreal and Terrestrial Habitats and |
| Insectivorous Mode of Feeding |
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 In some animals like the tree frog Hyla, fingers and toes bear adhesive pads that help in climbing and clinging to the trees. |
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 The presence of a prehensile tail is a common character in arboreal forms. |
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 Accessory organs for climbing like spines and tubercles are found in the forearm of some lemurs. |
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| All parasitic have successfully adapted to live either on or inside their hosts. Some of their important adaptations are: |
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 Presence of suckers or other structures for attachment to the host. (Tapeworm) |
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 Loss of locomotory, sense and digestive organs, especially in endoparasites as they are fully dependent on the host and draw their nourishment from it. |
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 Intermediate host and vector: To increase their chance of survival, many parasites have more than one host. |
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| E.g., Malarial parasite plasmodium has 2 hosts - female anopheles mosquito and man. |
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 Increased reproductive capacity - All successful parasites have very well developed reproductive organs and enormous productive capacity. |
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 Complicated life cycle - The production of enormous number of eggs and several larval forms by some endoparasites like Fasciola is an adaptation to maintain the continuity of the species. |
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