What is the largest mammal?

The largest mammal is the blue whale. This baleen whale is also the largest animal known to have existed, although some estimates for fragmentary prehistoric fossils remain debated.

Blue whales can exceed 30 metres in length, and the largest scientifically documented individuals weighed well over 100 tonnes. Females are generally larger than males. Their enormous size is supported by a highly efficient filter-feeding system: they engulf huge volumes of water and strain out krill through baleen plates.

The blue whale is sometimes confused with the fin whale, which is the second-largest living animal and can be longer in some individual measurements. The sperm whale is the largest toothed whale, while the African elephant is the largest land mammal. Blue whales were heavily hunted during the twentieth century and remain endangered, despite international protections.