ratite

/rat"uyt/, adj.

1. having a flat, unkeeled sternum, as an ostrich, cassowary, emu, or moa.

n.

2. a bird having a ratite breastbone.

[1875-80; < L rat(is) raft + -ITE²]

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Any bird species that cannot fly because its smooth, or raftlike, sternum (breastbone) lacks a keel to which flight muscles can be anchored.

The group includes some of the largest birds of all time. Two extinct types, the slow-moving, heavy-bodied elephant bird of Madagascar and the moas of New Zealand, grew to 10 ft (3 m) tall. Extant ratites include the cassowary, emu, kiwi, ostrich, and rhea.

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▪ bird

      any bird whose sternum (breastbone) is smooth, or raftlike, because it lacks a keel to which flight muscles could be anchored. All species of ratites are thus unable to fly. They are a peculiar and puzzling group, with anatomic anomalies. The group includes some of the largest birds of all time, such as the moa (q.v.) and the elephant bird (Aepyornis). Extant ratites include the ostrich, emu, cassowary, rhea, and kiwi (qq.v.).

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