Aliens arrive on Earth after a long journey, only to find that humanity has died out. They’ve never used writing or paper, so they don’t get books; they’ve never stored data digitally, so they don’t get computers. They recycle the books for fuel & the internet servers for chemicals. But their own typical data storage system looks & acts very much like a jackdaw, so they value the jackdaws & put them in beautiful jackdaw-friendly environments & spend the next 500 years reverently trying to decode the messages of hope they’re sure humanity left encoded in jackdaw behaviour. Jackdaws can’t believe their luck.