Classifications

• Mammals

• Birds

• Reptiles/Amphibians

• Fish

• Insects/Spiders

• Primitive Animals

• Extinct Animals

Mammals – a mammal has fur or hair and organs called mammary glands.  Mammals breathe air and they have backbones, well-developed brains, and four chambered hearts.  

Birds – a bird is an animal with feathers.  Birds have many qualities in common with mammals and reptiles, but it is their feathers that set them apart in the animal world.

Reptiles – their body temperature changes when the air temperature around them changes.  When reptiles sit on a rock in the sun, their body temperature rises.

Amphibians – they are slimy.  They have mucous glands in their skin which produces a slimy substance that helps them breathe through their skin as well as their lungs.

Fish – additional fins on the body’s midline, the dorsal and anal fins, and paired pelvic fins act as stabilizers to prevent rolling side to side.  Gills are made of a series of thin sheets or filaments through blood circulates.  As water moves into a fish’s mouth and passes over the gills, they dissolve oxygen across the thin gill membranes.  All fishes are vertebrates (backbones with gills for breathing).  Most fish have fins for swimming, scales for protection, and a streamlined body for moving easily through the water.  

Insects – small invertebrates.  Bodies are made up of a head, thorax, and abdomen.  Insects also have three pairs of legs and wings.  There are more than 900,000 known species of insects.  They are very adaptable to many environments.

Spiders –a few have adapted to freshwater life by trapping air bubbles underwater and carrying the bubbles with them.

Primitive Animals – included in this group are living invertebrates that are not contained with the orders of insects and spiders.  They include both land and marine animals, including crustaceans, mollusks, echinoderms (starfish and sea urchins) and annelids (worms).

Extinct Animals – extinct animals include both those species which have been lost relatively recently, as well as those which are more usually described as being prehistoric.  The animals classified as extinct, as opposed to prehistoric, are those that have existed within man’s lifetime and for whose disappearance man must often bear the responsibility.