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:

    For sounds in winter nights, and often in winter days, I heard the forlorn but melodious note of a hooting owl indefinitely far; such a sound as the frozen earth would yield if struck with a suitable plectrum, the very lingua vernacula of Walden Wood, and quite familiar to me at last, though I never saw the bird while it was making it.
    Henry David Thoreau (1817–1862)

    What bird so sings, yet so does wail?
    O, ‘tis the ravished nightingale!
    “Jug, jug, jug, jug, tereu,” she cries,
    And still her woes at midnight rise.
    Brave prick-song! who is’t now we hear?
    None but the lark so shrill and clear;
    John Lyly (1553–1606)

    My faith is the grand drama of my life. I’m a believer, so I sing words of God to those who have no faith. I give bird songs to those who dwell in cities and have never heard them, make rhythms for those who know only military marches or jazz, and paint colours for those who see none.
    Olivier Messiaen (1908–1992)