rhea: larger of two tall fast-running flightless birds similar to ostriches but three-toed; found from Brazil to Patagonia
vertebrate: animals having a bony or cartilaginous skeleton with a segmented spinal column and a large brain enclosed in a skull or cranium
night terror: an emotional episode (usually in young children) in which the person awakens in terror with feelings of anxiety and fear but is unable to remember any incident that might have provoked those feelings