Which animals can recognize themselves in the mirror?

While we are the only species to scrutinize our reflections in a mirror every day, we are not the only ones to recognize ourselves in reflective surfaces. 

Scientists have tested for mirror recognition in a wide array of species, starting with research on chimpanzees (Pan troglodytes) published in 1970. Animals ranging from ants to manta rays to African gray parrots (Psittacus erithacus) have been scrutinized for signs of self-awareness when presented with a mirror. A small handful realize that they are looking at themselves. Many don't. And a number have displayed inconclusive behaviors. 

These mixed results have led researchers to debate the usefulness of the test and how it helps scientists understand animal cognition. 

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"Many Animals don't pass," Frans de Waal, a primatologist at Emory University, told Live Science. De Waal has conducted self-awareness tests on capuchin monkeys — which failed. "They need to self-inspect a visual mark in front of a mirror without any training or rewards. It needs to be spontaneous. Most of the claims in the literature don't fit this description."

So which animals have passed the test?

In the 1970 chimp experiments, four chimpanzees were anesthetized and marked with red dye on their faces. When they awoke, they examined the areas that had been marked in the mirror, indicating an understanding that they were viewing themselves.