International Ornithologists' Union

The International Ornithologists' Union (IOU) is a member-supported and tax-exempt global organization dedicated to research in ornithology (avian biology) from ecosystems to molecules, linking basic and applied research, and nurturing education and outreach. It sponsors the quadrennial International Ornithological Congress, the first of which was held in 1884. The IOU seeks to support, promote and advance avian biology by: (1) disseminating ornithological knowledge; (2) interacting with other scientific organizations, foundations and institutions; (3) stimulating and strengthening locally-based research that includes the participation of amateur ornithologists; (4) cultivating collegial, collaborative and mutually supportive relationships among ornithologists internationally, without restrictions imposed by cultural or political differences; and (5) fostering knowledge transfer between basic research and applied sciences, such as conservation.

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Smallest bird

The smallest bird is the bee hummingbird (Mellisuga helenae) of Cuba and the Isle of Youth. Males measure 57 mm (2.24 in) in total length, half of which is taken up by the bill and tail, and weigh 1.6 grams (0.056 ounces). Females are slightly larger.