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.
Ornithoptera meridionalis
Ornithoptera meridionalis, the southern tailed birdwing, is the smallest species of the genus "Ornithoptera". It is known from a handful of localities in southeast Papua, New Guinea ("O. meridionalis meridionalis") and several localities along the south coast of Irian Jaya ("O. meridionalis tarunggarensis").