Invertebrates
What is an invertebrate? An animal that has no backbone Most animals in the world are invertebrates Most invertebrates are smaller than vertebrates.
Porifera Aquatic Multicellular Tiny pores all over their bodies Example: Sponge Porifera
Cnidaria Aquatic Soft-bodied Stinging tentacles Examples: Hydras Jellyfish Sea Anemones Coral
Hydra
Jellyfish
Sea Anemone
Coral
Worms No shells No legs No eyes Examples: Earthworms Tapeworms Sandworms
Mollusks May have a hard outer shell, but not always Examples: Snails Clams Squid Octopus slugs
Snail
Clams
Squid Squid
Octopus
Echinoderms Aquatic Spiny-skinned 5-part symmetrical body Examples: Starfish Sea Urchin Sand Dollar Sea Cucumber
Starfish
Sea Urchin
Sand Dollar
Sea Cucumber
Arthropods Jointed legs 2 or more body parts Head Thorax Abdomen Often have exoskeleton 850,000 species we know of so far!
Arachnids Two body parts: Cephalothorax Abdomen 4 pairs of legs Can regrow legs 8 eyes Poison glands in jaw Spinnerets on end of abdomen for webs
Don’t get ticked!
…or stung by a scorpion!
Crustaceans Head Thorax Abdomen 3 pairs of legs Swimmerets
Mmmm…lobster
Don’t be crabby!
Hey Shrimp!! Hey Shrimp!
Insects Head Thorax Abdomen 6 legs Compound Eyes
Millipedes Two pairs of legs per segment Rounded body Not poisonous
Centipedes One pair of legs per segment Flat body Poison claws behind head Paralyze prey
Aren’t invertebrates fun?