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
Loggerhead shrike length, tail length, and colour. "L. l. migrans" have a paler forehead than the top of the head. According to Mundy et al.’s 1997 study, there is a substantial genetic difference between the island subspecies "L. l. mearnsi" and the mainland subspecies "L. l. gambeli" due to a gene flow barrier between the two species. The loggerhead shrike is a medium-sized passerine. "Loggerhead" refers to the relatively large size of the head as compared to the rest of the body. It measures approximately 9 inches from bill to tail. The wing and tail length is about 3.82 and 3.87 inches