Sperm whale of the Society for Marine Mammalogy, the largest international association of marine mammal scientists in the world, officially uses "Physeter macrocephalus" when publishing their definitive list of marine mammal species. The sperm whale is the largest toothed whale, with adult males measuring up to long and weighing up to . By contrast, the second largest toothed whale (Baird's Beaked Whale) measures and weighs up to . The Nantucket Whaling Museum has a -long jawbone. The museum claims that this individual was long; the whale that sank the "Essex" (one of the incidents behind "Moby-Dick") was claimed to be . A
Blue whale to exist in real life, due to metabolic and energy constraints. Due to its large size, several organs of the blue whale are the largest in the animal kingdom. A blue whale's tongue weighs around and, when fully expanded, its mouth is large enough to hold up to of food and water. Despite the size of its mouth, the dimensions of its throat are such that a blue whale cannot swallow an object wider than a beach ball. The heart of an average sized blue whale weighs and is the largest known in any animal. During the first seven months