Arthropoda: A group of invertebrate animals having segmented body and jointed limbs. e.g. mosquito,fly crab, spider etc.
Aves:A group of vertebrate animals including all flying and non-flying birds.
Bird Migration: Seasonal migration of birds from one region to another. The inclemency of weather when makes the living of birds difficult at a place, they migrate to a region promising comfortable living.
Chordate:The major division of animal kingdom including man and all mammals, birds, reptiles, amphibia and fishes. Mostly they have backbones.
Hibernation:Period of dormancy in winter occurring in some mammals and in most reptiles and amphibians in colder parts of the world,also called winter sleep.
Mammal: Group of animals which include back boned hairy animals suckling its young e.g. man,dog etc.
Mollusca: Animals having a soft, unsegmented body usually covered with a hard shell e.g. snails,mussels etc.
Mutation:Discontinuous variation or sudden inheritable divergence of characteristics from ancestral type. These are parts of the raw material on which natural selection has acted to produce evolutionary change.
Pisces: A group of vertebrates including fishes e.g. lamprey,hag,sea horse,ray,shark etc.
Protozoa:Animals of microscopic size which include mostly unicellular animals e.g. amoeba,entamoeba etc.
Reptilia: A group of vertebrate animals that creeps or crawls e.g. snakes,lizards, alligator,turtle etc.
Vertebrata:A great division of chordate animals whose backbone(vertebral column) consists of vertebrae.