emperor penguin: the largest penguin; an Antarctic penguin
vertebrate: animals having a bony or cartilaginous skeleton with a segmented spinal column and a large brain enclosed in a skull or cranium
ornithischia: extinct terrestrial reptiles having bird-like pelvises: armored dinosaurs (thyreophorans); boneheaded and horned dinosaurs (marginocephalians); duck-billed dinosaurs (euronithopods)