When the first specimens were originally describedbyRichard Owen, they were placed within the genusDinornis as three different species, but, was later split off into their own genus, Emeus.[7]E. crassus is currently the only species of Emeus, as the other two species, E. casuarinus and E. huttonii are now regarded as synonyms of E. crassus. It has been long suspected that the "species" described as Emeus huttonii and E. crassus were males and females, respectively, of a single species. This has been confirmed by analysis for sex-specific genetic markers of DNA extracted from bone material; the females of E. crassus were 15-25% larger than males.[8] This phenomenon — sexual dimorphism — is not uncommon amongst ratites, being also very pronounced in kiwis.
Emeus was of average size, standing 1.5 to 1.8 metres (4.9–5.9 ft) tall, and weighing from 36 to 79kg.[9] Like other moa, it had no vestigial wing bones, hair-like feathers (beige in this case), a long neck and large, powerful legs with very short, strong tarsi. It also had a sternum without a keel and a distinctive palate.[10] Its feet were exceptionally wide compared to other moas, making it a very slow creature. Soft parts of its body, such as tracheal rings (cartilage) or remnants of skin were found, as well as single bones and complete skeletons. As they neared the head, the feathers grew shorter, until they finally turned into coarse hair-like feathers; the head itself was probably bald.[11]
Eastern moa lived only on the South Island, and lived in the lowlands (forests, grasslands, dunelands, and shrublands).[10] During the Last Glacial Maximum, it was confined to a single glacial refugium from which its range expanded during the Holocene.[12] Human colonists (specifically the Māori, who called them "moa mōmona")[1] hunted Emeus into extinction with relative ease. E. crassus was the second most common species found at the Wairau Bar site in Marlborough, where more than 4000 moa were eaten. The species had gone extinct by about 1400.[6]
^ abDavies, S. J. J. F. (2003). "Moas". In Hutchins, Michael (ed.). Grzimek's Animal Life Encyclopedia. Vol. 8 Birds I Tinamous and Ratites to Hoatzins (2 ed.). Farmington Hills, MI: Gale Group. pp. 95–98. ISBN0-7876-5784-0.
Eastern Moa. Emeus crassus. by Paul Martinson. Artwork produced for the book Extinct Birds of New Zealand, by Alan Tennyson, Te Papa Press, Wellington, 2006
