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
Varieties of Chinese Varieties of Chinese Chinese, also known as Sinitic, is a branch of the Sino-Tibetan language family consisting of hundreds of local language varieties, many of which are not mutually intelligible. The differences are similar to those within the Romance languages, with variation particularly strong in the more mountainous southeast. These varieties, often called "dialects", have been classified into seven to ten groups, the largest being Mandarin (e.g. Beijing dialect), Wu (e.g. Shanghainese), Min (e.g. Hokkien), and Yue (e.g. Cantonese). Chinese varieties differ most in their phonology, and to a lesser extent in vocabulary and syntax. Southern varieties tend to have