Exceptional exceptions are like unicorns: rare, mythical, and occasionally spotted in the wild. They're the outliers that defy explanation and make us all go "hmm, interesting."
Take, for example, the case of the exceptional behavior of the sea otter: when threatened, they release a foul-smelling secretion from their anal glands. It's like prophets and poets, but instead of words, they release a pungent aroma that says, "Stay away from me, I'm exceptional."
Or consider the exceptional creatures that inhabit our planet: the axolotl, with its gills and feathery appendages; the narwhal, with its spiraling tusk; the exceptional exception that is the platypus, with its bill, tail, and a heart that can't make up its mind.