Mimicry is perfectly standard behaviour for animals. There have been studies on how parents teach their offspring how to hunt dating back decades. This applies on land, on/under water and in the air. Most of the studies I have heard about involve mammals or birds, I can't remember any involving reptiles, fish or (in particular) insects. Some larger spiders may have this ability - ones large enough to eat small ground-nesting birds for instance
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The article itself is more about adapting behaviour by watching humans and that is self-limiting, apart from speech there is not much useful a bird can learn that way. I have a neighbour who used to look after the garden before it was turned into a lawn. Back then he had a fan - a blackbird which would hang around when he was digging, waiting for worms to be unearthed. It presumably recognised my neighbour as non-threatening and the digging as the same thing it would do but on steroids.
I was attacked by a goose a few years back. We were sitting outside and someone had fun throwing it scraps, closer and closer to me. It tried to drive me off by driving at me while hissing and flapping its wings. I joined in the fun by advancing on it, hissing back and 'flapping' my arms the same way. Communication was achieved, goose withdrew to a safer distance.