Overview of Organization of Information

The highest level of the classification system is the Kingdom. There are five Kingdoms into which all living organisms are classified. They include:

• Monera (the prokaryotic bacteria and blue-green algae – which do not have nuclear membranes or subcellular organelles).
• Protista (unicellular algae and protozoans – single celled organisms).
• Plantae (multicellular plants).
• Fungi (nonphotosynthetic plant like organism – e.g. Mushrooms).
• Animalia (multicellular animals).

The Kingdom of Interest: Animalia – the Multicellular Animals

The next level of importance in the classification system is the Phylla. The major Phylla of the Animalia kingdom are:

• Porifera (for example sponges).
• Cnidaria (for example aquatic jellyfishes).
• Ctenophora (for example aquatic sea walnuts).
• Platyhelminthes (for example tapeworms and liver flukes).
• Aschelminthes (for example roundworms).
• Annelida (for example earthworms).
• Mollusca (for example snails).
• Arthropoda (for example insects, ticks and spiders).
• Echinodermata (for example starfishes).
• Chordata (animals with a backbone e.g. goats, sheep, elephants, dogs).

The phyllum chordata (animals with a backbone) can be divided into eight classes:

• Four of these Classes are aquatic and are popularly known as fish (Classes Agnatha – primitive jawless fish, Placodermi – extinct primitive jawed fish, Chondrichthyes – cartilaginous fishes and Osteichthyes – bony fishes).
• The Class Amphibia – Frogs, Toads, Salamanders.
• The Class Reptilia – Turtles, Lizards, Snakes, Crocodiles and Alligators.
• Class Aves – the birds
• Class Mammalia – the Mammals (Animals with back-bones that produce milk for their young – from their mammary glands). The class Mammalia is divided into subclasses.

Some subclasses include:

• Subclass Prototheria, order – Monotremes (egg-laying mammals – duckbilled platypus),
• Subclass Theria, infraclass – Metatheria, order - Marsupials - for example Possums and Koalas,
• Subclass Theria, Infraclass – Eutheria - Placentals Order: Chiroptera – for example Bats,
• Subclass Theria, Order – Primates – for example Apes,
• Subclass Theria, Order – Carnivora – for example lions,
• Subclass Theria, Order – Pinnipedia – an aquatic order
• Subclass Theria, Order Perissodactyla and Artiodactyla – the hooved animals
• Subclass Theria, Order Proboscidea (for example elephants)
• Subclass Theria, Order Cetacea – for example whales