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Toothed whales have torpedo-shaped bodies with usually inflexible necks, limbs modified into flippers, no outer ears, a large tail fin, and bulbous heads (with the exception of the sperm whale family). Their skulls have small eye orbits, long beaks (with the exception sperm whales), and eyes placed on the sides of their heads.
Female beaked whales' teeth are hidden in the gums and are not visible, and most male beaked whales have only two short tusks. Narwhals have vestigial teeth other than their tusk, which is present on males and 15% of females and has millions of nerves to sense water temperature, pressure and salinity.
The family Balaenidae, the right whales, contains two genera and four species. All right whales have no ventral grooves; a distinctive head shape with a strongly arched, narrow rostrum, bowed lower jaw; lower lips that enfold the sides and front of the rostrum; and long, narrow, elastic baleen plates (up to nine times longer than wide) with fine baleen fringes.
Beaked whales are unique among toothed whales in that most species have only one pair of teeth. The teeth are tusk-like, but are only visible in males, which are presumed to use these teeth in combat for females for reproductive rights. In females, the teeth do not develop and remain hidden in the gum tissues. [11]
Baleen whales have no teeth; instead, they have plates of baleen, fringe-like structures that enable them to expel the huge mouthfuls of water they take in while retaining the krill and plankton they feed on. Because their heads are enormous—making up as much as 40% of their total body mass—and they have throat pleats that enable them to ...
Articles relating to the toothed whales (odontocetes, parvorder Odontocetiare), a parvorder of cetaceans that includes dolphins, porpoises, and all other whales possessing teeth, such as the beaked whales and the sperm whales. 73 species of toothed whales are described.
Now, sperm whales are protected under the Marine Mammal Protection Act. So, in order to sell the animal's tooth, it must be over 100 years old, and the owner has to know where it's been since the ...
Outside the upper one-rooted teeth and inside the upper two-rooted teeth there are pits for reception of the lower teeth. [14] Zygorhiza (and Dorudon) replaced their upper and lower deciduous first premolars with permanent teeth. This is very unusual in modern mammals and contrasts to extant toothed whales that only develop a single set of teeth.