Humans aren't the only animals that can recognize themselves in mirrors. All five species of great apes have passed the "mirror test" at some point — by eventually realizing a reflection isn't a doppelganger — and some monkeys have, too. Dolphins, orcas, elephants and even magpies are other members of this self-awareness club.
Of course, it's hard to tell what any animal really thinks when it looks in a mirror. A dog may bark or growl at first, but what does it mean when he loses interest? Does he know it's his reflection, or has he concluded that his evil twin is simply stuck in an alternate universe? Scientists look for certain reactions to test this — namely "self-directed behaviors," like using a mirror to groom or to remove a sticker from your face.
Still, the mirror test has plenty of critics. Passing it may indicate self-awareness, they argue, but failing it shouldn't imply self-unawareness. It's an inexact science.
That said, it's also pretty amusing to watch. The video below doesn't show actual mirror tests in a scientific sense, but it does offer a funny montage of how big cats react to their own reflections. In most cases, they don't seem to like what they see:
The video was filmed at Big Cat Rescue, a Florida nonprofit that bills itself as "the largest accredited sanctuary in the world dedicated entirely to abused and abandoned big cats." The facility is home to more than 100 exotic cats, most of which were abandoned, orphaned or rescued from abusive situations. Aside from managing all those cats, BCR produces educational videos about the risks of exotic pets, and pushes for regulations like the newly drafted Big Cats and Public Safety Protection Act.
To see what a more formal mirror test looks like, check out the videos below:
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