Smallest organisms
With a mass of approximately and a length of 5 centimetres (2.0 in), the bee hummingbird ("Mellisuga helenae") is the world's smallest bird species and the smallest warm-blooded vertebrate. Called the "zunzún" in its native habitat on Cuba, it is lighter than a Canadian or U.S. penny. It is said that it is "more apt to be mistaken for a bee than a bird". The bee hummingbird eats half its total body mass and drinks eight times its total body mass each day. Its nest is 3 cm across.
Melanocharitidae
The berrypeckers and longbills are small to very small songbirds. They range in length from in the case of the fan-tailed berrypecker to in the case of the pygmy longbill, which is the smallest bird in New Guinea. The berrypeckers ("Melanocharis") are usually bigger than the "Toxorhamphus" and "Oedistoma" longbills. The females of two species, the fan-tailed and streaked berrypecker, are unique amongst songbirds in that they exhibit a reversal in the usual pattern of sexual dimorphism, with the females being both longer and heavier. For example in the fan-tailed berrypecker the male weighs , whereas the female weighs .