There are over 80 species of whales, dolphins and porpoises, (1)_____ collectively as ‘cetaceans’, throughout the world. They come in all shapes and sizes. Here are some facts and figures about these incredible animals. The blue whale is (2)_____ animal on Earth. The average adult length is 25m for males and 26.2m for females, (3)_____ body weights of 90-120 tonnes. Hector’s dolphin is the world’s shortest cetacean. They may be only 1.2m long when fully (4)_____ . A blue whale eats up to 4 tonnes of krill daily. This is equivalent (5)_____  a fully grown African elephant every day. The sperm whale (6)_____ dive deeper than any other cetacean. They have been known to dive as deep as 2000m. One bowhead whale is reported to (7)_____  130 years old when it died. The sperm whale has the world’s heaviest brain (8)_____  can weigh up to 9.2kg. This compares (9)_____ the average 1.4kg for the brain of an adult human. The _baiji _dolphin, or Chinese river dolphin, is the rarest dolphin in the world and is reported to be endangered. It lives in the Yangtze River in China. Conservation measures (10)_____ by the Chinese to save it.