Odontocete

Odontoceti, or toothed whales, are one of the two main suborders of cetaceans, the other being Mysticeti (baleen whales). They include species such as dolphins, porpoises, beaked whales, narwhals and sperm whales. Odontocetes are distinguished by their dentition and reliance on echolocation. They possess teeth rather than baleen plates for feeding and use echolocation clicks to locate prey and navigate in dark or murky waters. Most have a single external blowhole, unlike the two blowholes of baleen whales. They also show a variety of skull and ear adaptations that support echolocation and precise sound reception.

Anatomically, odontocetes have a specialized structure known as a melon in the forehead that focuses ultrasonic sound produced by the nasal passages. The sound is emitted as clicks, and the returning echoes are received by the well-developed ears and middle ear, enabling high-resolution imaging of the surroundings and prey. Teeth in many species are simple cones, but some beaked whales have reduced dentition. Diets vary from fish and squid to other marine mammals in some groups.

Behaviorally, odontocetes are typically highly social and form dynamic groups or pods that can be stable over long periods. They vocalize extensively, producing species-specific whistles, clicks, and pulsed calls for communication, coordination while hunting, and social interaction. Many populations are resident in coastal areas, while others undertake long migrations.

There are more than 70 living odontocete species, distributed across several families, including dolphins and porpoises, beaked whales and the larger sperm, narwhal and beluga lineages. They face threats from bycatch, hunting, habitat degradation, pollution, and noise.