Animal Diversity Lecture 5

Ecdysis

Moulting of the cuticle layer

Round worms

Nematoda

Nematoda

aquatic habitats, soil, and within the tissues of plants and other animals, parasitic or free-living

Nematoda

Unsegmented Worms

C. Elegans

Model organism for development, aging, regeneration

Trichinella

Trichinellosis

Heart Worm

Dirofilaria

coelomates, exoskeleton, segmented bodies, jointed appendages

Arthropoda Characteristics

arthropoda

Occur in almost all habitats on earth

Trilobita, Cheliceriformes, Myriapoda, Crustacea, Hexapoda

Arthropoda Classification

Trilobita

Trilobites

Cheliceriformes

Spiders, mites, and scorpions

Myriapoda

Millipedes and Centipedes

Crustacea

Lobsters, crabs, barnacles, crayfish, shrimp, amphipods, isopods

Hexapoda

Insects

Trilobita

Extinct by Permian-Triassic boundary, all marine

Cheliceriformes

All terrestrial, "extinct by the end of Permian

Abdomen, Cephalothorax

Spiders have a _______ and a _________

Centipede

Single pair of legs per segment

Millipede

Multiple pairs of legs per segment

Centipedes

Carnivorous

Millipedes

Herbivorous

Hexapoda

nearly 1 million described species, actual diversity may be between 2 million to 50 million

Ecdysis

In arthropods each stage called an instar

pollinators

Arthropod beneficial Function?

plant destruction, invasive species, vectors,

Trouble with some arthropods?