Evolution of cetaceans "Caperea marginata") all have derived characteristics presently unknown in any cetothere and vice versa (such as a sagittal crest). The adaptation of echolocation occurred when toothed whales (Odontoceti) split apart from baleen whales, and distinguishes modern toothed whales from fully aquatic archaeocetes. This happened around 34 million years ago in a second cetacean radiation. Modern toothed whales do not rely on their sense of sight, but rather on their sonar to hunt prey. Echolocation also allowed toothed whales to dive deeper in search of food, with light no longer necessary for navigation, which opened up new food sources. Toothed whales
Greater white-toothed shrew and migration to empty breeding sites. Nonetheless, this dispersal pattern is a preventative measure for inbreeding. The greater white-toothed shrew can be very vocal."C. russula" can find their way around their environment via a primitive form of echolocation where they produce a high pitched twittering call to interpret their environment. The use of this laryngeal call and vibrissae allow the shrews to find their way around their environment. There have not been any concrete reports on the modes of communication used by this species,however, the vocalization and tactile and chemical cues likely to be used. The greater white-toothed shrew typically