I take issue with the way the old mirror test is administered by seeing if they react to a mark on their body only visible in a mirror. It doesn’t account for the fact that the animal might… just not give a shit if it’s marked. Dogs apparently fail the mirror test, but mine and plenty of other dogs will turn and look at you if they spot you in a mirror and you wave or do something to get their attention, so clearly dogs understand the concept of reflections enough to know what they’re looking at.