Bird blue Great Blue Heron against sunset about Flora and Fauna Biology

[, also called sundown in some American English dialects, is the time at which the Sun disappears below the horizon in the west. It should not be confused with dusk, which is the (variously defined) point at which darkness falls, some time after the Sun itself sets (which begins twilight).The red hues of the sky at sunset are caused by the Rayleigh scattering of blue light by atmospheric dust. Relatively little red light is scattered in this way, and so the sky often takes on shades of red, orange and yellow. The color of a sunset may be enhanced by atmospheric phenomena such as clouds, smoke and smog produced by natural processes or human activity, and by ash from volcanic eruptions. A number of eruptions in recent times, such as those of Mount Pinatubo in 1991 and Krakatoa in 1883, have been sufficiently large to produce remarkable sunsets (and sunrises) all over the world. See more at Wikipedia.org...]

>For other uses, see Bird (disambiguation). Many - see section below. Birds are bipedal, warm-blooded, egg-laying vertebrates characterized primarily by feathers, forelimbs modified as wings, and hollow bones. Birds range in size from the tiny hummingbirds to the huge Ostrich and Emu. Depending on taxonomic viewpoint, there are about 8,800–10,200 living bird species (plus about 120–130 that have become extinct in the span of human history) in the world, making them the most diverse class of terrestrial vertebrates. See more at Wikipedia.org...