Sharks have prowled all of Earth’s seas over the globe for almost 400 million years, making them older than most insects, amphibians, reptiles, and even flowers. Even at an older origin, their success is represented in somehow outlasting all five major mass extinctions over the Geological Time Scale and the different vast of amount of species lost as a result of each extinction. Today, sharks are included of approximately 8 orders, 40 families, 170 genera, and 430 species (Discovery Channel,2013). Some…
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