Cetacea and two (external) limbs that are modified into flippers. Though not as flexible or agile as seals, cetaceans can swim very quickly, with the killer whale able to travel at in short bursts and the fin whale able to cruise at . Dolphins are able to make very tight turns while swimming at high speeds. The hindlimbs of cetaceans are internal, and are thought to be vestigial. Baleen whales have short hairs on their mouth, unlike the toothed whales. Cetaceans have well-developed senses—their eyesight and hearing are adapted for both air and water, and baleen whales have a tactile system
White-toothed woodrat data provided by Macedo and Mares (1988) for what was then thought to be a single species applies to both. White-toothed woodrat Neotoma leucodon is a species of rodent in the family Cricetidae. Although originally named from San Luis Potosí, Mexico, as a species by Merriam, the white-toothed woodrat was long considered to be a synonym of the white-throated woodrat ("Neotoma albigula"). Molecular data, however, indicate the populations east of the Rio Grande in New Mexico and Trans-Pecos Texas represent a different species than morphologically similar populations west of the river. The habitat preferences of the two species appear similar,