Behold the terrifying ocean monster, Livyatan Melvillei! This predatory toothed whale lived 12-13 million years ago during the Miocene epoch and grew to 13.5 to 17.5 meters (45–57 feet) in length. A large adult whale could have weighed up to 50 tons. The extinct megapredator is named for Herman Melville and for the Biblical leviathan (“Livyatan” is from the Hebrew word for Leviathan). The great whale’s family is currently listed as “incertae sedis” which means “status uncertain,” a taxonomical place-holder used when biologists are trying to ascertain a creature’s relationship to other related organisms within a larger order.
In terms of body size, the modern sperm whale is probably slightly longer and heavier, but the livyatan had stronger jaws and much larger teeth. Paleontologists describe the mighty creature as having “the biggest tetrapod bite ever found,” which is no trivial matter, since the tetrapods include all mammals, reptiles (like dinosaurs), amphibians, and birds. Of course plankton feeders (like blue whales and whale sharks) have larger mouths, but the sperm whale and the livyatan have more powerful maws filled with large sharp teeth. The 36 centimeter (1.2 foot) long teeth of livyatan are the largest known teeth from the animal world which were used for eating (which is to say the tusks of elephants, walruses, Odobenocetops, and narwhals tusks were larger, but were not used for biting into plants or animals).
Livyatan Melvillei presumably swam the deep blue ocean hunting for seals, dolphins, baleen whales and whatever other sea creature was large enough to command its attention (giant sharks, huge squid, huge fish, and bizarre giant birds?). Like the sperm whale it seems to have had a spermaceti organ in its head although it is unclear if this was used for echolocation, auditory signaling, or aggressive male sexual display (i.e. head-butting). It must have been quite a (horrifying) sight to see one of these giant monsters biting apart a 10 meter (33 foot) long baleen whale. Sadly, the ever-changing dynamic of ocean life caused the great toothed whale to go extinct at approximately the same time as megalodon, the largest known shark (which was a contemporary of the great whale). Numerous websites speculate which great animal would have won an ocean duel–which is foolish, since whales are clever animals and thus the obvious victor.