Yes, horses are one of a rare group of species who appear to have self-awareness and are able to recognise themselves in a mirror. The testing process is called mirror self-recognition (MSR). The degree of recognition appears to be variable and is not a black-and-white skill.
Self-awareness or self-consciousness is an important concept as it goes to whether an animal can think objectively about themselves which also goes to the sophistication of their emotions. It affects many aspects of cognition and therefore behaviour.
Humans know they are looking at themselves in a mirror. Often the don’t like what they see because they retain an image of themselves which is divorced from reality. In my view cats are not self-aware as they see another cat in the mirror.

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What about horses? The BBC reports on a University of Pisa study: If horses had toes: demonstrating mirror self recognition at group level in Equus caballus, which concluded that horses recognise themselves in mirrors.
When horses look at themselves in a mirror they first check what they are looking at by, for instance, looking behind the mirror and performing what the scientists called ‘contingency behaviours’ such as peek-a-boo and head and tongue movements. Then they “used the mirror surface to guide their movements towards their coloured cheeks, thus showing that they can recognize themselves in a mirror.”
It seems that the scientists put colouring on the horses’ cheeks, which the horses saw in the mirror and wanted to remove. They found that 11 out of 14 horses (almost 80%) tried to rub off the coloured marks from their cheeks when they saw their reflections.
Self-recognition or self-awareness is seen in animals with known high levels of intelligence such as bottlenose dolphins, magpies and elephants. Is the first study to demonstrate that horses can be added to this select group?
The scientists involved were: Paolo Baragli, Chiara Scopa, Veronica Maglieri and Elisabetta Palagi.
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