lancets
Tunicates
Lampreys and hagfishes
Amphioxus
pharyngeal slits
gills or lungs
jawless
hermaphroditic
buried in the sand
lancets
notochord
hollow nerve tube
birds and mammals
fishes, amphibians & reptiles
warm-blooded
spine
nervous system
coldblooded
post anal
urochordates
exoskeleton
deuterostomes
muscular tail
invertebrates, like insects
tunicates
echinoderms and chordates