Loggerhead sea turtle turtle is debated, but most authors consider it a single polymorphic species. Molecular genetics has confirmed hybridization of the loggerhead sea turtle with the Kemp's ridley sea turtle, hawksbill sea turtle, and green sea turtles. The extent of natural hybridization is not yet determined; however, second-generation hybrids have been reported, suggesting some hybrids are fertile. Although evidence is lacking, modern sea turtles probably descended from a single common ancestor during the Cretaceous period. Like all other sea turtles except the leatherback, loggerheads are members of the ancient family Cheloniidae, and appeared about 40 million years ago. Of the six species
Loggerhead shrike be energetically stressed and underweight. Insects are consumed in mid-flight, but vertebrates usually require more handling time and therefore more energy. Due to the shrike's small size in proportion to the size of its prey, it must rely on specialized adaptations to facilitate its hunting. The powerful, hooked beak of the loggerhead shrike allows it to sever the neck of a small vertebrate. Larger prey are subjected to impaling, in which they are pushed down into a sharp projection, such as a thorn or barbed wire. The bird can then tear off flesh by using the projection as an anchor.