You may have read the earlier blog about ‘Clever Hans’, the horse who was able to answer difficult mathematical questions, not however by working them out himself, but by reading the subtle signals given off his human handlers. Although being able to respond to human signals was an impressive feat in itself, people were disappointed to learn he was not working out the answers himself as they had initially thought. However, new research suggests that although horses may not be able to answer mathematical questions, they can count!

(c) Compassion/Ed Posposil
As reported in the Daily Telegraph, the story of Clever Hans inspired Dr Claudia Uller, of the University of Essex, to investigate whether horses can count.
Dr Claudia Uller and Jennifer Lewis carried out experiments using 57 untrained horses belonging to local private owners and a local riding school. Before the tests, the horses were allowed to nibble a small piece of real apple in to get them interested in the activity. In the experiments, real apples were replaced with fake apples so that the horses would not be influenced by their sense of smell.
In each test, the horses watched plastic apples being dropped out of sight into buckets. In the first test, two plastic apples were placed in one bucket and three in another. The buckets were held up at head level so that horses could choose one. Eleven out of thirteen horses selected the bucket containing three apples, which suggests that the horses understood which bucket had the larger number of apples in it.
The second experiment followed the same pattern, but this time one bucket contained two small apples and the other contained a single large apple with double the surface area. Again the horses chose the bucket with the greater the number of apples – ten out of the twelve horses tested chose the bucket holding the two apples.
The horses were able to keep a tally of how many apples were going into each bucket, and hold this information in their heads before deciding which bucket to investigate. This tendency to opt for containers holding larger numbers of food items has also been seen in non-human primates such as rhesus macaques and lemurs. Baby chicks of only 3 or 4 days old can add and subtract too. Human babies develop this ability at about ten months of age.
Although horses may not be able to count in the same way that humans do, this study demonstrates that they do understand the concept of ‘greater or fewer’, and that horses are certainly more intelligent than people may have previously thought.
More about horses’ abilities, behaviour and welfare
See our blog article on the fascinating report about horses written specially for Compassion by animal welfare consultant Heather Pickett.
Sources
http://www.telegraph.co.uk/science/science-news/3338537/Horses-can-count-new-study-says.html
http://www.breakingnews.ie/world/mhojgbaucwid/
