The largest extant species of bird measured by mass is the common ostrich (Struthio camelus), closely followed by the Somali ostrich (Struthio molybdophanes). A male ostrich can reach a height of 2.8 metres (9.2 feet) and weigh over 156.8 kg (346 lb),[1] A mass of 200 kg (440 lb) has been cited for the ostrich but no wild ostriches of this weight have been verified.[2] Ostrich eggs are the largest of any bird, averaging 1.4 kg (3.1 lb).[3]
The largest wingspan of any extant bird is that of the wandering albatross (Diomedea exulans) of the Sub-Antarctic oceans. The largest dimensions found in this species are an approximate head-to-tail length of 1.44 m (4.7 ft) and a wingspan of 3.65 m (12.0 ft).
The largest bird of all time was likely the elephant bird Aepyornis maximus, which was estimated to have weighed 275–1,000 kilograms (610–2,200 lb) and stood at 3 metres (9.8 ft) tall.[4][5]
The largest wingspan of all time likely belonged to Pelagornis sandersi at roughly 5.2 m (17 ft).[6] P. sandersi was also likely the largest bird to ever fly.[7]
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