ANIMALS - ESSENTIAL POINTS

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Animals found on earth are very diverse in nature.

Different creatures have different habitat and feeding habits, modes of locomotion and many other characteristics.

Habitat

The surroundings where organisms live. It has two components Biotic (living things like plants and animals) and Abiotic (non-living things like rocks, soil, air and water).

Types of Habitat:

• Terrestrial Habitat: Plants and animals live on land. Example: forest, grasslands, deserts, coastal and mountain ranges.
• Aquatic Habitat: Plants and animals live in water. Example: ponds, swamps, lakes, rivers and oceans.
• The animals which can live both on land as well as in water are called amphibians, e.g., frogs and toads. These animals require water for fertilization and they lay their eggs in water only.

Adaptations

Presence of specific features or certain habits which enable an organism to live in its surrounding.

 Terrestrial:

• Deserts: Small animals stay in borrows deep in sand during day, and come out at night. In plants, leaves are either absent or very smell as spines. stem has a thick waxy coating. roots go deep into the soil. Example, cactus, camels, rats etc.
• Mountains: Animals have thick skin or fur. mountain goat has strong hooves. Trees are cone shaped having sloping branches, leaves are needle like. Example, cedas, pines, spruce, mountain goat etc.
• Grasslands: Animals are light brown in color and speed is important for survival as there are few places to hide. Plants have deep roots, narrow leaves and flexible stems. Example, deer, elephants, grass, shrubs etc.
• Forests: A forest is a type of habitat that has dense population of trees and many species live in forest. Example, bear, snake, lion, oak, cottonwood, banyan etc.

Aquatic:

• Ponds:
  • Animal adaptation: Animals like fishes, ducks, tortoise live in ponds.
  • Plants with roots fixed in soil: Stems are long, hollow and light. leaves float on water. Example, water lily, lotus.
  • Plants with roots submerge: Leaves are narrow and thin ribbon-like. Example, duckweed, green algae etc. 

• Oceans:
  • Animals have streamlined body, gills to respire (dolphins and whales have blowholes).
  • Animals like squids and octopus do no have streamlined body and stay deep in water.

Feeding Habits

Animals need food to get energy and stay healthy. Animals differ from each other in feeding habits. Their feeding habits depend on type of food they eat.

• Rodents : Animals like squirrels, mice and rabbits are called rodents. They have sharp front teeth to gnaw at seeds and fruits.
• Land animals
  • Plant eating animals like cow, goat, sheep, deer are called Herbivores. Their front teeth are well suited to eat grass and plants. They have sharp front teeth to bite the leaves and strong flat grinding teeth to chew their food.
  • Animals like wolf, lion and tiger eat flesh of other animals. They are called Carnivores These animals have sharp, pointed and curved front teeth to tear the flesh and strong grinding teeth to crush the bones.
  • Animals like bear and dog eat both plants and flesh of animals. They are called Omnivores.
• Scavengers : Animals like hyena and jackal feed on the flesh of dead animals. They are called scavengers. They help in keeping the forest clean.
• Aquatic animals
  • Whale and shark feed on algae, planktons and small fish.
  • Carnivorous fish eat earthworms, larvae of mosquito, fruit flies and other fish.
  • Herbivorous fish eat peas, cucumber and potatoes.
  • Omnivorous fish are also known as mud-eaters. They feed on algae and micro organisms.
• Birds
  • Birds have beaks and claws to catch or eat their food.
  • Some birds eat flesh only whereas some feed on plants and fruits.
  • Eagles and vultures have strong and hooked beak to tear flesh.
  • Pigeons and sparrows have strong, hard and short beaks to eat grains.
  • Parrots have curved beaks to crack nuts.
  • Swallows have short and broad beaks to catch flying insects.
  • Woodpecker has chisel shaped beak to make a hole in a stem of tree. 
• Insects
  • Most insects feed on plants and other insects.
  • Insects are important pollinators.
  • They help flowers, fruits, vegetables and other plants spread and grow.
  • Most spiders eat freshly killed food after trapping their prey in their web.
  • Butterfly suck nectar of flowers.

Breathing

Breathing is the body process of taking in oxygen and giving out carbon dioxide. All animals need energy. Oxygen burns the food within their bodies and release energy for performing different activities.

• Mammals, reptiles and birds breathe through lungs
  • Air is take in through nose and reaches lungs through wind pipe.
  • Mammals have 2 lungs. One on each side of heart.
  • The lungs are supplied with blood vessels.
  • When air enter lungs an exchange of gases takes place between air and blood vessels.
  • Blood in lungs absorbs oxygen from air and gives up carbon dioxide.
  • Air containing carbon dioxide is breathed out.
  • Whale does not take its oxygen from water. It comes to surface of water to take in oxygen from air.

• Fishes breathe through gills
  • Fish take in oxygen through gills and at same time, carbon dioxide in their blood is dispersed into water.
  • Animals like crabs, prawns and oyesters have gills to breathe.

• Amphibians breathe through gills and lungs
  • Tadpoles breathe through gills. But adult frog breathe through lungs on land and through its moist skin underwater.
  • Microbes like amoeba and paramecium breathe through their skin.
  • Earthworm breathe through skin.

• Insects breathe through air tubes or holes
  • There are large number of holes on bodies of insects through which they breathe. They are called spiracles.
  • Spiracles lead to network of branching tubules called trachea.
  • Air is pumped into the tubes and then carried out to all tissues.
  • These tissues take in oxygen from the tubes and give out carbon dioxide into the tubes.

Movement

Animals move from one place to another in search of food, shelter and to protect them from enemies.

Most land animals have 4 limbs. 2 limbs at back are called hind limbs and 2 limbs at front are called fore limbs.

• Mammals
  • Animals like cow, horse, tiger etc. use their 4 limbs to move while man and kangaroo are the mammals who use 2 hind limbs to move.
  • Bat is also a mammal but it can’t walk. It has wings.

• Birds
  • Birds have wings which help them to fly. Birds have hind limbs.
  • Birds can perch, hop and walk with hind limbs.
  • Birds like kiwi, emu and ostrich can’t fly. They are called flightless birds.

• Insects
  • Insects are largest group of animals on earth.
  • Insects have 6 legs.
  • Grasshopper use its long hind legs to hop.
  • Insects like wasps and butterflies have wings to fly.
  • Dragonfly cannot fold their stretched legs.

• Aquatic animals
  • Fishes have fins and tail to move in water.
  • Frog has longer hind limbs to jump and hop. Frog also has webbed feet to swim.
  • Penguins are peculiar birds found near south pole. They don’t fly but use their short wings as flippers to swim.

• Reptiles
  • Reptiles like lizard, crocodile and snake have various methods to move.
  • Some use legs and some use scaly skin to move.
  • Crocodiles have 4 short limbs to crawl.
  • Snake uses its scales to crawl with help of his strong muscular system and a flexible backbone.

• Humans
  • Humans are terrestrial animals. They use one pair of limbs to support their body.
  • Humans are most developed creatures on the earth.
  • Humans use their brain to control other creatures.

• Migration
  • Migration is the movement of animals from one region to another, in response to changes.
  • Birds migrate twice a year during summer and autumn. These birds are called migratory birds.
  • Birds who do not migrate are called resident birds.
  • Some birds from other countries like storks, cranes and mallard ducks visit India every winter.
  • Arctic tern travels between Arctic and Antarctic twice a year.

 Body coverings of animals

• Scales: Fishes are covered by overlapping scales that are flexible. The bodies of reptiles like snake, crocodile and lizard are covered with scales.

• Shell: Animals like snail, tortoise and turtle are covered by a shell. These animals withdraw their head and feet into the shell when feel dangerous situations.

• Wool or Fur:  Sheep’s body is covered with wool and bear’s body is covered with fur that protect them from rain and cold.

• Feathers: Birds are covered with feathers. Feathers help them to fly and protect the birds from rain and cold.

• When birds focus its both eyes on two different things, it increases its range of vision.
• Cow sleeps for 4 hours, snake sleeps for 18 hours, giraffe sleeps for 2 hours and car sleeps for 12 hours.
• Ears of tigers can move in different directions. Tigers mark their area with their saliva.
• Fangs are 2 hollow teeth of snake through which it injects its poison.
• Euglena is a fresh water organism. As it can prepare its own food as well as can obtain food from other plants and animals, so, it is both plant like and animal like.