I've read that "all dolphins are whales". I've also read that "the killer whale (orca) is a type of dolphin" and that "orcas are not whales, they're dolphins."
But if the orca is a dolphin and all dolphins are whales, aren't orcas whales?
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Sign up to join this communityI've read that "all dolphins are whales". I've also read that "the killer whale (orca) is a type of dolphin" and that "orcas are not whales, they're dolphins."
But if the orca is a dolphin and all dolphins are whales, aren't orcas whales?
When common names are misleading, it can help to look at the taxonomy. Cetaceans include both MYSTICETES (baleen whales) and ODONTOCETES (toothed whales). Odontocetes include the family Delphinidae (dolphins), which includes the orca species (Orcinus orca).
I think your confusion might stem from the common use of the word "whale" to sometimes refer to mysticetes in particular (baleen whales) and sometimes refer to cetaceans as a whole (including both mysticetes and odontocetes). And to be extra confusing, the common name of Orcinus orca is "killer whale", but it is a "whale" (in the sense of a cetacean) in the dolphin family.
Does that help?
Here is another article from the International Fund for Animal Welfare that dives into this question quite nicely.
All dolphins are whales but all whales are not dolphins. Orca, the killer whale is the largest member of oceanic dolphin family.