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They may be numerous, with some dolphins bearing over 100 teeth in their jaws. At the other extreme are the narwhals with their single long tusks and the almost toothless beaked whales with tusk-like teeth only in males. [20] In most beaked whales the teeth are seen to erupt in the lower jaw, and primarily occurs at the males sexual maturity. [21]
Orcinus meyeri is a fossil species of Orcinus (killer whales) found in the Early Miocene deposits of southern Germany, known from two jaw fragments and 18 isolated teeth. It was originally described as Delphinus acutidens in 1859, but reclassified in 1873. Its validity is disputed, and it may be a synonymous with the ancient sperm whale ...
The orca (Orcinus orca), or killer whale, is a toothed whale and the largest member of the oceanic dolphin family. It is the only extant species in the genus Orcinus and is recognizable by its black-and-white patterned body. A cosmopolitan species, it is found in diverse marine environments, from Arctic to Antarctic regions to tropical seas.
The killer whale pod in Mexico hunts and attacks much larger whale sharks by targeting them from below, a study finds ... tiny teeth that it doesn’t use as a defense mechanism,” said Francesca ...
However, the killer whale–which preys on large marine mammals–is not known to exhibit these fractures, though this may be because killer whale teeth are more resistant to shock, having a smaller pulp cavity and, thus, a thicker tooth. Further, terrestrial carnivores that chew through bone display these fractures, and those that prey on ...
In comparison, the modern killer whale has teeth around 8 cm (3.1 in) in height and 2.5 cm (0.98 in) in diameter. [3] Like the modern killer whale, the tooth lacks a coat of cementum. However, unlike the modern killer whale, O. paleorca had a circular tooth root as opposed to an oval, and the pulp extended more towards the back than the front. [2]
The cross-sections of the teeth are rounded or oval. A characteristic feature is that the dentin forms in layers that alternate directions giving it a banded appearance. Their teeth are second in hardness to hippopotamus ivory. Sperm whale teeth may grow up to 20 cm (8 inches) in length while the killer whale teeth are slightly smaller.
The genus Orcinus was published by Leopold Fitzinger in 1860, [4] its type species is the orca named by Linnaeus in 1758 as Delphinus orca.Taxonomic arrangements of delphinids published by workers before and after Fitzinger, such as John Edward Gray as Orca in 1846 and Orca (Gladiator) in 1870, are recognized as synonyms of Orcinus.