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( Snake)
A snake is an elongate reptile of the suborder Serpentes. Like all reptiles, snakes are ectothermic and covered in scales. All snakes are carnivorous and can be distinguished from legless lizards by the lack of eyelids, hind limbs and external ears. Snakes are found on every continent except Antarctica and range in size from the tiny, 10&_160;cm long thread snake to pythons and anacondas of up to 7.6&_160;m (25&_160;ft) in length. In order to accommodate snakes' narrow bodies, paired organs (such as kidneys) appear one in front of the other instead of side by side. Most species are non-venomous and those that have venom use it primarily to kill and subdue prey rather than for self-defense. A few possess venom potent enough to cause painful injury or death to humans. Snakes are thought to have evolved from either burrowing or aquatic lizards during the Cretaceous period (c 150 Ma). The diversity of modern snakes appeared during the Paleocene period (c 66 to 56 Ma). A literary word for snake is serpent, a Middle English word which comes from Old French, and ultimately from *serp-, "to creep"[1], also e?p? in Greek. The serpent is also a symbol of medicine due to its association with Asclepius, the Greek god of medicine. Fifteen families are currently recognized comprising 456 genera and over 2,900 species.[2][3] The fossil record of snakes is poor because snake skeletons are typically small and fragile, making fossilization uncommon. However 150 million-year-old specimens readily identifiable as snakes with lizard-like skeletal structures have been uncovered in South America and Africa.[4]11 There is consensus, on the basis of morphology, that snakes descended from lizards.[5][4]11 Fossil evidence suggests that snakes may have evolved from burrowing lizards, such as varanids or a similar group during the Cretaceous Period.[6] An early fossil snake, Najash rionegrina, was a two-legged burrowing animal with a sacrum, and was fully terrestrial.[7] One extant analog of these putative ancestors is the earless monitor Lanthanotus of Borneo, although it also is semi-aquatic.[8] Subterranean forms evolved bodies that were streamlined for burrowing and lost their limbs.[8] According to this hypothesis, features such as the transparent, fused eyelids (brille) and loss of external ears evolved to combat subterranean conditions such as scratched corneas and dirt in the ears.[8][6] Some primitive snakes are known to have possessed hindlimbs but their pelvic bones lack a direct connection to the vertebrae. These include fossil species like Haasiophis, Pachyrhachis and Eupodophis, which are slightly older than Najash.[9]
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Relief for Phobias by Phone by Michelle Beaudry
You've Had Enough Pain and Suffering You're tired of being afraid, and you're ready to change. Phobias limit your life at every turn, and you're all done feeling limited. You need a plan to make the change. Read on, my friend, and let me help you...
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