Leatherback sea turtle million years ago during the Cretaceous period. The dermochelyids are relatives of the family Cheloniidae, which contains the other six extant sea turtle species. However, their sister taxon is the extinct family Protostegidae that included other species that did not have a hard carapace. Leatherback turtles have the most hydrodynamic body design of any sea turtle, with a large, teardrop-shaped body. A large pair of front flippers powers the turtles through the water. Like other sea turtles, the leatherback has flattened forelimbs adapted for swimming in the open ocean. Claws are absent from both pairs of flippers. The leatherback's flippers
Spanish dialects and varieties which is the preferred form in formal settings, and is considered indispensable in academic and literary writing, the media, etc. This standard tends to disregard local grammatical, phonetic and lexical peculiarities, and draws certain extra features from the commonly acknowledged canon, preserving (for example) certain verb tenses considered "bookish" or archaic in most other dialects. Spanish dialects and varieties Some of the regional varieties of the Spanish language are quite divergent from one another, especially in pronunciation and vocabulary, and less so in grammar. While all Spanish dialects adhere to approximately the same written standard, all spoken varieties differ from