Originally, the ceremony used a variety of rodents and mustelids, but over time most people agreed it made sense to standardize on a specific individual ground squirrel in Pennsylvania.
Funny, but ackchyually this attempted "proof" involves setting up a context with words and a visual border, so it is not a proof "without words, pictures or content of any kind", just like how a gestalt image cannot be constructed from empty space alone.
'Ugh, I'm never going to be like spiders. My descendants will all just be normal arthropods who mind their own busines and don't do anything weird.' --The ancestor of a bunch of eusocial insects