They really don’t like it.

You might not know that a lot of animals can’t recognize themselves in a mirror. While there are some that appear to be able to view their reflection and think “that’s me,” others see a mirror as a window to another world — one in which there’s someone who looks exactly like them copying everything they do.

Consequently, many of these animals react with a mix of surprise and anger, which can be seen here:

Animals seeing themselves in the mirror for the first time.
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