Whale a large tail fin, and flat heads (with the exception of monodontids and ziphiids). Whale skulls have small eye orbits, long snouts (with the exception of monodontids and ziphiids) and eyes placed on the sides of its head. Whales range in size from the and dwarf sperm whale to the and blue whale. Overall, they tend to dwarf other cetartiodactyls; the blue whale is the largest creature on earth. Several species have female-biased sexual dimorphism, with the females being larger than the males. One exception is with the sperm whale, which has males larger than the females. Odontocetes, such as
Blue whale of its life, a blue whale calf drinks approximately of milk every day. Blue whale calves gain weight quickly, as much as every 24 hours. Even at birth, they weigh up to —the same as a fully grown hippopotamus. Blue whales have proportionally small brains, only about , about 0.007% of its body weight, although with a highly convoluted cerebral cortex. The blue whale penis is the largest penis of any living organism and also set the Guinness World Record as the longest of any animal's. The reported average length varies but is usually mentioned to have an average length