animal kingdom

• vertebrates: mammals, birds, reptiles, amphibians, fish
• invertebrates - arthropods: insects, arachnids, crustaceans, myriapods
• arthropods - have jointed legs
• myriapods - body has many segments. each segment has jointed legs
• insects - body divided into 3 parts: head, thorax & abdomen
• insects - have 3 pairs of jointed legs and 2 pairs of wings
• arachnids - have 4 pairs of jointed legs
• arachnids breathe through gills called book lungs
• crustaceans - have more than 4 pairs of jointed legs
• crustaceans breathe through gills