Bird

Bird

Birds (class Aves) are feathered, winged, bipedal, endothermic (warm-blooded), egg-laying, vertebrate animals. With around 10,000 living species, they are the most speciose class of tetrapod vertebrates. All present species belong to the subclass Neornithes, and inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from the 5 cm (2 in) Bee Hummingbird to the 2.75 m (9 ft) Ostrich. The fossil record indicates that birds emerged within theropod dinosaurs during the Jurassic period, around 160 million years (Ma) ago. Paleontologists regard birds as the only clade of dinosaurs to have survived the Cretaceous–Paleogene extinction event 65.5 Ma (million years) ago.

Read more about Bird.

Famous quotes containing the word bird:

    The bird would cease and be as other birds
    But that he knows in singing not to sing.
    The question that he frames in all but words
    Is what to make of a diminished thing.
    Robert Frost (1874–1963)

    I never saw a wild thing
    Sorry for itself.
    A small bird will drop frozen dead
    From a bough
    Without ever having felt sorry for itself.
    —D.H. (David Herbert)

    Time, as is well known, sometimes flies like a bird and sometimes crawls like a worm, but human beings are generally particularly happy when they don’t notice whether it’s passing quickly or slowly.
    Ivan Sergeevich Turgenev (1818–1883)