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The giraffe is one of only two living species of the family Giraffidae, along with the okapi. The family was once much more extensive, with numerous other species. The giraffids evolved from a 3 metres (9.8 ft) tall antelope-like mammal that roamed Europe and Asia some 30–50 million years ago.
The earliest known giraffid was Climacoceras, which still resembled deer, having large antler-like ossicones. It first appeared in the early Miocene epoch. Later examples include the genera Palaeotragus and Samotherium, which appeared in the early to mid-Miocene. They were both tall at the shoulder, and had developed the simple, unbranched ossicones of modern giraffids, but still had relatively short necks.
Comparison of the African Miocene giraffids: Palaeotragus (two top) and Climacoceras (two bottom)From the late Pliocene onwards, the variety of giraffids drastically declined, until only the two surviving species remained. The modern genus Giraffa evolved during the Pliocene epoch, and included a number of other long-necked species, such as Giraffa jumae, that do not survive today.[7] Alan Turner proposes, in the 2004 book Evolving Eden, that giraffe ancestors initially had a dark coat with pale spots, and that the spots gradually became star-shaped, before eventually forming the reticulated pattern found today.[8] The modern species, Giraffa camelopardalis, appeared during the Pleistocene 1 million years ago.
The evolution of the long necks of giraffes has been the subject of much debate. The standard story is that they were evolved to allow the giraffes to browse vegetation that was out of the reach of other herbivores in the vicinity, giving them a competitive advantage. However, an alternative theory proposes that the long necks evolved as a secondary sexual characteristic, giving males an advantage in "necking" contests to establish dominance and obtain access to sexually receptive females. This theory notes that giraffes frequently feed from relatively low-lying shrubs, and that the necks of males are significantly longer than those of females.[9] However, this theory is not universally accepted, and some of the data supporting it has recently been challenged, lending support to the original proposal that neck length is related to browsing habits.
(http://en.wikipedia.org/wiki/Giraffe)

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Additional Photos by Vasilis Protopapas (vasilpro) Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 2755 W: 87 N: 5133] (41761)
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