Odontoceti

Odontoceti, commonly known as toothed whales, are a suborder of the Cetacea that includes all living whales with teeth. In contrast to baleen whales, odontocetes use teeth to grasp prey and rely on echolocation to navigate, hunt, and communicate. They breathe air through a single external blowhole and are found in oceans worldwide, from coastal zones to the deep sea, with several species also inhabiting freshwater rivers.

Taxonomy and diversity: Odontoceti comprises several living families, including Delphinidae (oceanic dolphins such as the bottlenose dolphin and the killer whale), Monodontidae (narwhal and beluga), Phocoenidae (porpoises), Ziphiidae (beaked whales), Iniidae (Amazon river dolphin), Platanistidae (South Asian river dolphin), Pontoporiidae (franciscana), Lipotidae (baiji), and the sperm whale family Physeteridae, along with Kogiidae (pygmy and dwarf sperm whales). The suborder also contains numerous extinct lineages. Extant odontocetes range from small porpoises to large beaked and sperm whales, occupying both marine and freshwater ecosystems.

Anatomy, behavior, and ecology: Odontocetes generally have teeth suited for grasping rather than chewing. They exhibit diverse social structures, with many species forming groups or pods and producing a variety of vocalizations for communication and coordination. Echolocation is used to locate prey and navigate complex environments. Beaked whales are notable for deep, lengthy dives, while sperm whales hunt squid at great depths. Diets vary by species, but fish and cephalopods are common staples.

Distribution and conservation: Odontocetes inhabit oceans worldwide and several river systems. They face threats from bycatch, habitat degradation, pollution, and hunting, with some species classified as endangered. The baiji (Lipotes vexillifer) is widely cited as extinct in the early 21st century, highlighting the conservation challenges facing this diverse suborder.