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The toothed whales (also called odontocetes, systematic name Odontoceti) are a clade of cetaceans that includes dolphins, porpoises, and all other whales with teeth, such as beaked whales and the sperm whales. 73 species of toothed whales are described.
The whale then pushes the water out, and animals such as krill are filtered by the baleen and remain as a food source for the whale. Baleen is similar to bristles and consists of keratin, the same substance found in human fingernails, skin and hair. Baleen is a skin derivative. Some whales, such as the bowhead whale, have
Odontocetes, such as the sperm whale, possess teeth with cementum cells overlying dentine cells. Unlike human teeth, which are composed mostly of enamel on the portion of the tooth outside of the gum, whale teeth have cementum outside the gum. Only in larger whales, where the cementum is worn away on the tip of the tooth, does enamel show.
Consequently, its tooth count was lower than those sperm whales, and, aside from the modern dwarf (Kogia sima) and pygmy (K. breviceps) sperm whales, it had the lowest tooth count in the lower jaw of any sperm whale. [1] [8] The most robust teeth in Livyatan were the fourth, fifth and sixth teeth in each side of the jaw. The well-preserved ...
The common name was chosen because the part of the tooth that protrudes from the gums (unlike the strap-like teeth of strap-toothed whales) has a shape similar to the tip of a flensing spade as used by 19th-century whalers. Despite the rather similar dentition, the spade-toothed whale and strap-toothed whale seem to be only distantly related.
Each species' teeth have a characteristically unique shape. In some cases, these teeth even hinder feeding; in the strap-toothed whale, for example, the teeth curve over the upper jaw, effectively limiting the gape to a few centimeters. Females are presumed to select mates based on the shape of the teeth, because the different species are ...
The sperm whale has 18 to 26 teeth on each side of its lower jaw which fit into sockets in the upper jaw. [56] The teeth are cone-shaped and weigh up to 1 kilogram (2.2 lb) each. [57] The teeth are functional, but do not appear to be necessary for capturing or eating squid, as well-fed animals have been found without teeth or even with deformed ...
Like in other raptorials, and unlike in the modern sperm whale, Zygophyseter had tooth enamel. [8] [9] [10] Like in Acrophyseter, the mandibular foramen takes up about 40% of the lower jawbone. The teeth of the upper jaw form an angle of nearly 120 degrees between the crown and the root, which is possibly a characteristic shared by all ...