• Natural Perspective: Animal Kingdom- Arthropodia; Mollusca; Echinodermata; Cnidaria
• The Animal Kingdom (Animalia) Natural Perspective Ari Kornfeld
• Popular Groups on the Tree of Life

mammals (including humans), birds, reptiles, amphibians, fish and other vertebrates, but not all chordates are vertebrates. All have (some in embryo) pharyngeal slits, dorsal nerve cords,notochords, cartilaginous rods, post-anal tails.

• Vertebrata Animals with backbones Tree of Life
• Phylum Chordata University of Minnesota. Department of Ecology, Evolution, and Behavior.
• Kingdom Animalia University of Michigan - Museum of Zoology
• Phylum and Class of Australian Aquatic Invertebrates Links to keys Lucid Central
• Phylum and Class of Australian Aquatic Invertebrates Lucid Central
• Subkingdom Protozoa University of Minnesota. Department of Ecology, Evolution, and Behavior.

radially or biradially symmetric,stinging cells called nematocysts Sea anemones, corals, jellyfish, sea pens, hydra

• Cnidaria (Coelenterata) Sea anemones, corals, jellyfish, sea pens, hydra Tree of Life
• Phylum Cnidaria University of Michigan - Museum of Zoology
• Classification of Gelatinous Zooplankton Jellies zone
• Phylum Cnidaria University of Minnesota. Department of Ecology, Evolution, and Behavior
• Introduction to the Cnidaria Jellyfish, corals, and other stingers. . University of California Museum of Paleontology
• The Cnidaria University of California, Irvine
• Cnidaria BMLSS British Marine Life Study Society
• The Phylum Cnidaria Earth-Life

Arthropodia

Phylumjoint-footed animals that possess a hard, armor-like outer skeleton, exoskeletons that contain chitin, and jointed legs.Arachnida, Insecta, Crustacea

• Key to Orders of Australian Aquatic Arthropoda Lucid Central
• Phylum Arthropoda The Science Room Howe High School Howe, Oklahoma
• Arthropoda Insects, spiders, crustaceans, etc. Tree of Life
• Understanding Arthropod Classification and Identification
• Gary A. Dunn
• Arthropod Classification Department of Biological Sciences EKU Summary
• Introduction to the Arthropoda . . . the REAL rulers of the Earth. . . University of California Museum of Paleontology
• Phylum Arthropoda University of Michigan - Museum of Zoology
• Phylum Arthropoda University of Minnesota. Department of Ecology, Evolution, and Behavior
• Joint-Legs (Arthropoda) Natural Perspective Ari Kornfeld

eight-legged creatures spiders, scorpions, and ticks

• Key to Freshwater Arachnids (Spiders & Mites) Lucid Central
• Spiders ID CSIRO Entomology
• Arachnida Spiders, mites, scorpions, whipscorpions, pseudoscorpions Tree of Life
• Arachnids - Introduction Meet Some Spooky Spiders Queensland Museum
• Araneae Spiders University of California Museum of Paleontology
• Arachnology The study of arachnids (spiders and their relatives) The Arachnological Hub of the World Wide Web
• Arachnida Class University of Michigan - Museum of Zoology

exoskeleton divided into three parts, three pairs of legs, one pair of antennae, compound eyes, and many adults are winged.

moths, stinkbug, ants, bees, beetles, butterflies, flies, grasshoppers, wasps

• Australian Insects Names CSIRO Entomology
• Encarsia species of Australia and the Pacific Islands Stefan Schmidt CSIRO Entomology important biological control agents of whiteflies and scale insects.
• Australian Ants Online CSIRO Entomology
• Insecta Class University of Michigan - Museum of Zoology
• Wonderful world of Insects Earth-Life
• Insecta Insects Tree of Life
• Class:Insecta The Spencer Entomological Museum at the University of British Columbia, Vancouver, Canada

hard bodies.

lobsters, shrimps,crayfish, crabs, and barnacles.

• Subphylum Crustacea University of Michigan - Museum of Zoology
• Crustacea.net Australian Museum
• Key to Families Australian Cristacea CSIRO Entomology
• Crustacea Crabs, lobsters, shrimp, barnacles, sow bugs, etc. Tree of Life
• Crustacea Marine Biologists

Porifera Phylum

Sponges

• Porifera Sponges Tree of Life
• Phylum Porifera (sponges) University of Michigan - Museum of Zoology
• Phylum Porifera The Sponges University of Minnesota. Department of Ecology, Evolution, and Behavior
• Introduction to Porifera University of California Museum of Paleontology
• Sponges Encarta

segmented worms

marine worms earthworms and leeches, polychaetes

• Annelida Segmented worms: bristleworms, ragworms, earthworms, leeches and their allies Tree of Life
• Phylum Annelida Biology Iowa State
• Phylum Annelida The Segmented Worms University of Minnesota. Department of Ecology, Evolution, and Behavior
• Introduction to the Annelida Everybody's favorite, worms. . . University of California Museum of Paleontology
• Phylum Annelida (segmented worms) University of Michigan Museum of Zoology.

a soft body which is often covered by a shell

Clams, Snails, Squids, Octopuses,sea slugs

• Sea Slug Forum
• Snail, seaslugs: molluscs Australian Museum
• Key to Families of Australian Aquatic Molluscs Lucid Central
• The phylum Mollusca Zoology Study Guide Life Science Department Potchefstroom University for Christian Higher Education
• Phylum Mollusca University of California Online course in Marine Biology
• Phylum Mollusca University of Minnesota. Department of Ecology, Evolution, and Behavior
• Mollusca Snails, clams, mussels, squids, octopi, chitons, and tusk shells Tree of Life
• Phylum Mollusca University of Michigan Museum of Zoology.

bilaterally symmetrical, worm-like organisms that are surrounded by a strong, flexible noncellular layer called a cuticle

roundworms, hookworms Trichina worms, pinworms, filarial worms

• Nematoda: A Key to Nematodes of the Murray-Darling River System and coastal freshwaters of southeastern Australia M. Hodda. CSIRO
• Phylum Nematoda University of Michigan Museum of Zoology.
• Nematoda Roundworms Tree of Life
• Phylum Nematoda The Round "Worms" University of Minnesota. Department of Ecology, Evolution, and Behavior.

bilateral symmetry

flatworms

• Phylum Platyhelminthes The Flat "Worms" University of Minnesota. Department of Ecology, Evolution, and Behavior.
• Key to Class and Order of Australian Aquatic Flatworms
• Lucid Central
• Platyhelminthes Flatworms, tapeworms, flukes Tree of Life
• Phylum Platyhelminthes (flatworms) University of Michigan Museum of Zoology.
• Introduction to the Platyhelminthes Life in two dimensions. . . University of California Museum of Paleontology

calcareous endoskeleton,water vascular system ("tube feet"), pentameral fivefold symmetry

sea urchins, starfish, sea cucumbers

• Phylum Echinodermata University of Minnesota. Department of Ecology, Evolution, and Behavior.
• Echinodermata Spiny-skinned animals: sea urchins, starfish, and their allies Tree of Life
• Introduction to the Echinodermata . . . from starfish to sea cucumbers. . . University of California Museum of Paleontology
• Phylum Echinodermata
• University of Michigan Museum of Zoology.
• Phylum Echinodermata Bellarmine University Department of Biology