Can you explain the analogy of whale is to dolphin as otter is to salmon?

The analogy "whale is to dolphin as otter is to salmon" highlights relationships within a group of marine animals. Just as a whale and a dolphin are both mammals that share similar habitats and traits, an otter and a salmon are both associated with aquatic environments, but they represent different roles; otters are mammals that hunt and consume fish like salmon. This analogy illustrates the connection and distinction between different species within their respective categories.