Chordates - a hollow nerve cord - a notochord - animals having: - a hollow nerve cord - a notochord - a supporting rod under the nerve cord - pharyngeal pouches - a tail beyond the anus

Chordate Groups 1) Nonvertebrate chordates a) Tunicates - filter feeding aquatic animal having chordate features only as a larva b) Lancelets - fish-like animal without fins or vertebrate

- ectotherms (cold-blooded) 3 groups 1) Jawless fish (hagfish) - aquatic vertebrates with fins, scales, & gills - ectotherms (cold-blooded) 3 groups 1) Jawless fish (hagfish) 2) Cartilaginous fish (sharks & rays) 3) Bony fish (flounder,trout,etc.)

- vertebrate that lives in water as a larva and on land as an adult 3) Amphibians - vertebrate that lives in water as a larva and on land as an adult - larva = gills adult = lungs - ectotherms - some gas exchange through skin EXAMPLES:

- vertebrate animal - lungs - lives on land - lays eggs 4) Reptiles - vertebrate animal - lungs - lives on land - lays eggs - dry, scaly skin - ectotherm EXAMPLES:

5) Birds - vertebrate animal - 2 legs - feathers - lungs - wings - lays eggs - endotherm (warm-blooded) - light-weight bones

6) Mammals - vertebrate animal - lungs - hair covering body - 4 chambered heart - mammary glands to - endotherms nurse young - live birth Groups MONOTREMES - egg-laying mammals

MARSUPIALS - mothers carry under-developed young in a pouch. EXAMPLES:

PLACENTALS - mothers carry embryo internally - placenta provides embryo with nourishment - many groups ( carnivores, insectivores, primates, etc.) EXAMPLES: