Insects, crustaceans, spiders, scorpions, Oh My! Arthropods

In every part of the world! Monarch Butterfly on milkweed

Orb Weaver Spider, Giant Centipede (Arizona)

Arthropod = Jointed Foot (Appendage) Poda = Foot Arthro = Joint Arthropod = Jointed Foot (Appendage)

Bilateral symmetry

Distinguishing Characteristics Tough Exoskeletons Jointed Appendages Segmented Bodies

Exoskeleton Outer Skeleton Protects Organs from Injuries Waxy Coating Allowing for Waterproofing Disadvantages: heavy, growth

Jointed appendages Moveable Extensions of Body Allow for Movement May be Modified for Breathing, Feeding, or Flying Disadvantages: heavy, growth

Segmented Bodies Specialized Segments Each class has specific segments Disadvantages: heavy, growth

Other Characteristics True Coelom (internal body cavity) Open Circulatory System Respiration through body surfaces, gills, tracheae or lungs Demonstrate Cephalization Arteries with no capillaries

Classification of aRTHROPODS

Class aRACHNIDA Spiders, scorpions, mites Cephalothorax and abdomen 4 pairs of legs Fang like claws, spinneretes for creating webs Wolf Spider, Black Widow

Class Diplopoda Millipedes 2 pairs of legs on each body segment Eat decaying plant material

Class Chilopoda Centipedes 1 pair of legs on each body segment Feed on insects, earthworms, slugs

Class crustacea crayfish, lobsters, crabs, pill bugs, barnacles cephalothorax 2 pairs of antennae mainly aquatic Exoskeleton made of calcium carbonate

Class insecta most successful land arthropods head, thorax, abdomen each thoracic segment has a pair of legs (some may have wings) 3 pairs of mandibles

And the Star of the Week...