Interactive cetacean anatomy: explore every organ

Click on any part of the killer whale’s body below to discover its anatomy: the blowhole that closes with a muscular flap, the melon that focuses echolocation sounds, the rete mirabile that manages blood pressure on deep dives, the three-chambered stomach, the brain (5.5 kg in the killer whale, 8.5 kg in the sperm whale, the outright record in the animal kingdom), the throat pleats of the rorquals that unfold to engulf several tonnes of water in one go… Switch between the external view (visible parts) and the internal view (organs in section) with the buttons at the top of the diagram.

This page is aimed in particular at teachers (upper primary, lower secondary, upper secondary biology) and curious pupils. All the annotations are sourced from the detailed glossary and FAQ pages on the site. To dig into a topic, click the links in each organ record.

Cetaceans are marine mammals entirely adapted to aquatic life: their organs have undergone spectacular transformations in only 50 million years since their land-dwelling ancestor Pakicetus. Understanding their anatomy means understanding how evolution sculpts the body of a quadruped into a streamlined body able to dive to 3,000 metres, to produce sounds at 236 dB or to travel 16,000 km a year.