Horses have the intelligence to recognise their reflection in a mirror, a new study has discovered.
Scientists from Italy painted a small letter X on the faces of 11 of the animals who attempted to remove it once they realised it was there in a mirror.
The discovery means horses could be among the most self-aware creatures on the planet, alongside primates.
A few other species such as elephants and bottle-nosed dolphins have been noted recognising themselves but scientists do not know if species as a whole had the ability.
The study, published in the Animal Cognition journal, suggests horses have the same self-awareness only seen in primates
The findings were published in the journal Animal Cognition.
Dr Paolo Baragli from the University of Pisa in Italy said: ‘Here, we report the first evidence of mirror self-recognition at the group level in a non-primate species.
‘The marks were placed on both cheeks because the panoramic visual field of horses does not cover this head area and, therefore, the mark could be seen by the tested horse only with the guidance of the mirror.
‘Our horses used the mirror surface to guide their movements towards their faces previously marked, thus showing that they are able to recognize themselves in a mirror. They followed a sequence of behavioural steps towards the mirror before being marked.
‘Our horses engaged in contingency behaviours similar to those reported for other species such as head movements, peek-a-boo, and tongue protrusion almost exclusively in presence of the reflective surface’
A letter X was painted on the faces of the horses out of its eyeline in ultrasound gel
Most of the animals checked behind the mirror at first to look for the other horse in its pen
To start with 14 animals from the Italian Horse Protection Rescue Centre in Tuscany, Italy, were videoed when they encountered a mirror.
All at first thought it was another animal which some tried to play with and others showed aggression towards. Another horse showed fear.
Eleven of the 14 checked behind the mirror as if looking for its counterpart and later moved their heads to see their reflection do the same.
Some stuck their tongues out.
Those 11 had an X dabbed on their faces of gel used for ultrasounds.
Some of the horses showed aggression towards its reflection at first but scientists say they eventually realised it was themselves in the mirror
They were then recorded and eventually all made attempts to remove the shape which they would not have been able to see if not for the mirror in their stall.
The report reads: ‘The horses tested in our pilot study showed some behavioural patterns in response to the presence of the reflecting surface which were not performed in the other conditions.
‘Therefore, differences in the attentional behaviour toward the mirror are ascribable to the presence of the reflecting surface rather than to the object itself.’
Other experts were sceptical of the findings.
Gordon Gallup, a psychologist at the University at Albany in New York, said: ‘None of the horses spontaneously used the mirror to investigate parts of their bodies that could not be seen without a mirror.’