Part of the "Branches on the Tree of Life" series. Worms with segmented bodies make up the phylum Annelida. Explores the three classes of annelids: Class Polychaeta (feeding, locomotion, and larval stages), Class Oligochaeta (lifestyles, feeding adaptations, and anatomy of freshwater oligochaetes and earthworms), and Class Hirudinea (leeches, crayfish, and worms show adaptations for commensal, parasitic, and scavenger lifestyles). DNA evidence places annelids close to the molluscs on the tree of life. Accessibility options on the DVD are: (1) expanded description, (2) English subtitles in a black box, (3) subtitled description.