The two parvorders, baleen whales (Mysticeti) and toothed whales (Odontoceti), are thought to have diverged around … See more

Cetacean bodies are generally similar to those of fish, which can be attributed to their lifestyle and the habitat conditions. Their body is well-adapted to their habitat, although they share essential characteristi… See more

Cetaceans have powerful hearts. Blood oxygen is distributed effectively throughout the body. They are warm-blooded, i.e., they hold a nearly constant body temperature.
Cetaceans have lungs, meaning they breathe air… See more

Cetaceans are found in many aquatic habitats. While many marine species, such as the blue whale, the humpback whale and the orca, have a distribution area that includes nearly the entire ocean, some species oc… See more

Conscious breathing cetaceans sleep but cannot afford to be unconscious for long, because they may drown. While knowledge of sleep in wild cetaceans is limited, toothed cetaceans in captivity have been recorded t… See more