Cetaceans are a group of aquatic mammals that includes whales, dolphins, and porpoises. They have a streamlined body shape, blowholes for breathing, and flippers for swimming. They range in size from the 1.5 meter (5 foot) vaquita porpoise to the 30 meter (98 foot) blue whale.
Cetaceans inhabit a variety of aquatic environments, including oceans, rivers, and estuaries. Some species, such as the humpback whale, migrate between different habitats depending on the season.
Cetaceans are carnivorous and their diet typically consists of fish, squid, and krill. Some larger species such as the baleen whales filter feed on plankton.
Cetaceans display a wide range of behaviors. Some species are solitary, while others are highly social. They communicate through a variety of vocalizations, and many species engage in cooperative hunting and other social behaviors.
There are around 90 species of cetaceans, divided into two suborders: the Odontoceti (toothed whales) and the Mysticeti (baleen whales). The Odontoceti include species such as dolphins, killer whales, and sperm whales, while the Mysticeti include species such as humpback whales, gray whales, and bowhead whales.