The Orca (Orcinus orca), also known as the Killer Whale, is the largest member of the oceanic dolphin family. It is the second-most widely distributed mammal on Earth (after humans) and is found in all the world's oceans. more...
It is also a versatile predator, eating fish, turtles, birds, seals, sharks and even other juvenile and small cetaceans. This puts the Orca at the pinnacle of the marine food chain. The orca also attacks other whales, in particular Gray Whales.
The name "killer whale" reflects the animal's reputation as a magnificent and fearsome sea mammal that goes as far back as Pliny the Elder's description of the species. Today it is recognized that the Orca is neither a whale (except in the broad sense that all cetaceans are whales) nor a danger to humans. No attack on a human by an Orca in the wild has ever been recorded. There have, however, been isolated reports of captive Orcas attacking their handlers at marine theme parks.
A former name for the species is Grampus. This is now seldom used and should not be confused with the Grampus genus (containing Risso's Dolphin).
The name "Orca" (plural "Orcas") was originally given to these animals by the ancient Romans, possibly borrowed from the Greek word ὄρυξ which (among other things) referred to a species of whale.
The name "killer whale" is widely used in common English. However since the 1960s "orca" has steadily grown in popularity as the common name to identify the species and is now more popular than the traditional name amongst those in the field.
There are several reasons for the change. First, having the word whale in the name of a species that is really a dolphin causes confusion. Second, the species is called orca in most other European languages and, as there has been a steady increase in the amount of international research on the species, there has been a convergence in naming.
Furthermore, the killer in "killer whale" is often wrongly assumed to imply that the creature is a killer of humans, an attitude amplified by an unfortunate movie seeking to capitalize from the buzz from Jaws (1975). Orca: The Killer Whale (1977) starred Richard Harris and Bo Derek. It is thought this long standing and often fearful reputation can be put to rest by using the more neutral name of orca.
A pod of Orcas is capable of taking down a large whale. It is commonly thought that 18th-century Spanish sailors dubbed these creatures asesina-ballenas, or "whale killer" for this reason. However, this title was improperly translated into English as "killer whale". The term became so prevalent that Spanish speakers commonly used its retranslation of ballena asesina. This practice has further strengthened the case for using orca.
There are still many who prefer the original name, believing it to be an appropriate description of a species that does indeed kill many animals, including other cetaceans. These supporters of the original name point out that the naming heritage is not limited to Spanish sailors. Indeed the genus name "Orcinus" means "from Hell" (see Orcus) and although the name "orca" (in use since antiquity) is probably not etymologically related, the assonance might have given some people the idea that it means "whale that brings death," or "demon from hell."
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