Humans have taught gorillas to communicate with sign language, why not cats? Here's a gem that's been bouncing around the internet for a while and worth a watch.
For those who know American Sign Language, this cat is spot-on with her gestures asking for food. While kitty can't make a squished 'O', her gesture of putting food in her mouth is unambiguous. Just watch the following video.
One can argue the cat's conditioned to act in a certain way to beg for food, but people who are owned by cats certainly know there's something more behind their inscrutible countenances.
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