Resources: Animal kingdom
Vertebrates are animals with internal backbones made of interlocking bones called vertebrae. They make up 4% of the animal kingdom . There are five major groups of vertebrates – fish, birds, reptiles, amphibians and mammals.
Invertebrates are animals that do not have an internal skeleton of bones. They make up 96% of the animal kingdom . Invertebrates include molluscs, echinoderms, worms, jellyfish, sponges, protozoans and arthropods.
Arthropods make up about 83% of the animal kingdom. These animals have external skeletons, jointed legs and segmented bodies. Species include crabs, prawns, spiders, scorpions, insects, centipedes and millipedes.
Fish – 1.8%
Vertebrate. With scales or leathery skin, fish live in water and take in oxygen through gills. Some fish lay eggs; others bear their young live. Cartilaginous fish (sharks and stingrays) have skeletons of gristle. Bony fish (goldfish and herring) have skeletons of bone.
Amphibians – 0.4%
Vertebrate. Amphibians undergo metamorphosis during life, changing from aquatic larval forms with gills to terrestrial forms with lungs. They lay soft-shelled eggs in water. They are ectothermic (or cold-blooded) – their body temperature varies with the environmental temperature. Species include frogs, toads, newts and salamanders.
Reptiles – 0.6%
Vertebrate. Reptiles are terrestrial animals with lungs and waterproof skin, which is covered with scales. They lay eggs with a membranous shell. They are ectothermic
(or cold-blooded) – their body temperature varies with the environmental temperature. Species include snakes, lizards, tortoises, turtles, crocodiles and alligators.
Birds – 0.86%
Vertebrate. Birds are terrestrial, warm-blooded, air-breathing animals. They have a body covering of feathers and scales on their legs and feet. Their front limbs are modified as wings. The majority of species can fly. They have a beak (rather than teeth) for feeding. They lay hard-shelled eggs.
Mammals – 0.38%
Vertebrate. Mammals are terrestrial, warm-blooded, air-breathing animals. They have a body covering of fur or hair. They bear live young. Three major types:
 montremes – platypus and echidna are the only mammals which lay eggs
 marsupials – carry their young in a pouch
 placentals – young grow in the womb and are born at an advanced stage of development.
Insects – 71.26%
Invertebrate. Arthropod. Insects have an exoskeleton, three distinct body segments
(head, thorax and abdomen) and six legs on the middle segment. They have one pair of antennae and compound eyes. When insects reproduce, usually there is an egg
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Resources: Animal kingdom phase, a caterpillar stage and a process of metamorphosis that produces the adult form. The largest single animal group on Earth, with more species than all the other groups combined.
Arachnids – 5.22%
Invertebrate. Arthropod. Arachnids have an exoskeleton, eight legs and no antennae.
Species include spiders, scorpions, ticks and mites. They are mostly terrestrial.
Crustaceans – 4.27%
Invertebrate. Arthropod. Crustaceans are mostly aquatic (live in water). They have an exoskeleton, two pairs of antennae and breathe by gills. Species include crabs, prawns, lobsters, barnacles and slaters.
Centipedes and millipedes – 2.2%
Invertebrate. Arthropod. Centipedes are segmented animals with one pair of legs on each segment and one pair of long antennae. Millipedes have two pairs of legs on each segment and one pair of short antennae. Both are terrestrial.
Molluscs – 4.75%
Invertebrate. Unsegmented animals with soft bodies, which are often protected by a single or double shell. They have well-developed body systems including a large, muscular ‘foot’. They are terrestrial, freshwater or marine. Species include snails, slugs, clams, mussels, octopus, squid and cuttlefish.
Worms – 3.43%
Invertebrate. These soft-bodied animals are scavengers, which clean up left-over organic material. Three types are:
 segmented worms – body divided into a number of similar sections; include earthworms, leeches, bristle worms and sand worms
 flatworms – unsegmented worms with flattened bodies; many are parasitic; include tapeworms and flukes
 roundworms – unsegmented, cylindrical worms; mostly small and parasitic; best known is the pinworm, which lives in the human large intestine.
Protozoans – 2.92%
Invertebrate. Animals consisting of one cell only. Sometimes protozoa group together as a colony. They move by tiny hair-like structures called cilia, by whip-like structures called flagella, or by a crawling motion. All are microscopic and must live in water.
Some are parasitic and cause diseases such as malaria, sleeping sickness and dysentery.
Jellyfish and corals (Cnidarians)
– 0.86%
Invertebrate. These animals have soft bodies composed of only two cell layers with an intervening layer of jelly. All live in water and most are sea dwellers. A ring of tentacles around the mouth carries stinging cells, which are used to capture prey.
Their digestive system is a sac-like structure with only one opening. Other species include sea anemones and sea wasps.
Echinoderms – 0.58%
Invertebrate. Unsegmented animals with body parts in fives. They collect food and move about by using a system of water-filled tubes ending in suction cups. Some have a skeleton of internal limy plates, which join to make a rigid ‘shell’. Others are soft-bodied. All live in the sea. Species include starfish, sea urchins, brittle stars and sea cucumbers.
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Resources: Animal kingdom
Sponges (Poriferans) – 0.47%
Invertebrate. Simple animals composed of two cell layers with little cell specialisation.
Their bodies are covered in tiny holes or pores, which give the group its name. Water passes through these pores bringing food into the cells. All live in water and most are sea dwellers.
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