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It is known that modern mysticetes have teeth initially and then develop baleen plate germs in utero, but lose their dentition and have only baleen during their juvenile years and adulthood. However, developing mysticetes do not produce tooth enamel because at some point this trait evolved to become a pseudogene. This is likely to have occurred ...
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]
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 ...
And sperm whales function as a family, "Sperm whales are often spotted in groups (called pods) of some 15 to 20 animals. Pods include females and their young, while males may roam solo or move ...
The degree of calcification varies between species, with the sei whale having 14.5% hydroxyapatite, a mineral that coats teeth and bones, whereas minke whales have 1–4% hydroxyapatite. In most mammals, keratin structures, such as wool , air-dry, but aquatic whales rely on calcium salts to form on the plates to stiffen them. [ 58 ]
In terms of length, blue whales have often been compared to three school buses lined up back to back. These whales measure 90-100 feet long and are estimated to weigh from 200,000-352,000 pounds ...
Animals that do not whisk, but have motile whiskers, presumably also gain some advantage from the investment in musculature. Dorothy Souza, in her book Look What Whiskers Can Do [35] reports some whisker movement during prey capture (in cats, in this case): Whiskers bend forward as the cat pounces. Teeth grasp the mouse tightly around its neck.
A San Diego-based ecotour operator has captured stunning aerial footage, perhaps first of its kind, showing Cuvier’s beaked whales swimming along the surface. Rare footage shows elusive ...