I've got a memory of our late little cat when from she was about 2 years old. She was out in the back garden, eyeing up a butterfly which had settled on the buddlea in the middle of the garden. Its wings began to twitch and soon the butterfly took off. Our cat leapt after it, the butterfly wafted skywards and puss landed in the buddlea with her posterior in the air. Very ungainly and funny to watch!
And another of our family corgi decades ago - she was out on the pavement when she saw something small-ish and white across the road. Luckily the road, although wide, was very quiet, because poochie gave chase in an instant, undoubtedly thinking it was a cat. When she got across the road, it became clear to her that it was a polly bag. She looked sooo embarrassed - if dogs can blush, she blushed!