...it might only be a mechanical "digesting" duck.
Such was one of the iconic inventions of the dawn of the mechanical age, "The Duck." The steampunk creature of clockwork limbs could not only move, but simulate eating food and - sparing no effort in attention to detail - pass droppings as well, although the actual product was pre-stored and didn't involve actual biological digestion.
Such was the invention of Jacques de Vaucanson, widely considered to be one of the fathers of robotics or at least automata. He created this duck in 1738, for demos to the elite, using it to finance further creations.
Before you scoff too loudly at such frivolity, keep in mind that Vaucanson's major accomplishments included automated, programmable looms, which could be programmed with punch cards - in 1745. Later this same media storage format would be used to input data into the world's first computers.
You can still generate a punched-card design at emulators like this. I would recommend the 'bcd' command from the bsdgames package on Unix systems, but that's such lost technology that it's barely worth mentioning.