Horses Show Unexpected Intelligence in Planning Experiment

Horses taking part in a new experiment displayed unexpected intelligence, apparently choosing to ignore the rules of a game so they could obtain the most treats with the least effort.

"Horses are not natural geniuses," says Carrie Ijichi, an equine scientist at Nottingham Trent University in England. "They are thought of as mediocre, but this study shows they're not average and are in fact more cognitively advanced than we give them credit for."

Relatively little research has examined how horses learn, although some studies have suggested they can grasp the basic consequences of their choices.

Nottingham Trent University ethologist Louise Evans and her colleagues set out to explore whether these large herbivores live mainly in the moment or have some awareness of what lies ahead. Their findings support something many horse lovers may already suspect: horses can plan ahead, and they do so.

How the horse experiment tested planning

The researchers tested 20 horses by offering each one a treat for touching a target made from a piece of card. However, no reward was given when the target appeared with a light switched on.

The light was intended as a ‘stop’ signal. Even so, the horses kept nudging the target with their noses and ate their treats once the light went out.

That behaviour could easily be taken as a sign that the horses did not understand the game. Evans and her colleagues point out, however, that there are other possible explanations. The animals might have understood but lacked the behavioural inhibition to stop, suggesting impatience; they might have needed more time than they were given to learn a second signal; or they might have been ‘cleverly’ weighing up costs and benefits.

Horses change tactics when errors carry a cost

To tell these possibilities apart, the researchers added a cost. If a horse touched the card incorrectly while the ‘stop’ light was on, it faced a 10-second timeout during which it had no chance of receiving a reward.

"We were expecting horses' performance to improve when we introduced the time-out, but were surprised by how immediate and significant the improvement was," says Evans.

"Animals usually need several repetitions of a task to gradually acquire new knowledge, whereas our horses immediately improved when we introduced a cost for errors. This suggests that the horses knew all along what the rules of the game were."

The team believes the horses initially nudged the targets indiscriminately because they could still get regular rewards without the effort of checking what the light meant. They appeared to ignore the stop signal as part of a cost-benefit strategy, then changed tactics as soon as a greater cost was introduced. That switch suggests a degree of forward planning previously considered beyond horses.

The result indicates that they can anticipate future events and adjust their behaviour to meet a goal: in this experiment, getting more treats for minimal effort.

What the findings suggest about horse intelligence

"We now think that horses may be able to use a form of learning called 'model-based learning' which was thought to be too complex for them. This will now help us to understand their behaviour and capabilities much better," explains Ijichi.

"It's fascinating because they have a very underdeveloped prefrontal cortex which is what we typically credit with producing that type of thinking in humans. This means they must be using another area of the brain to achieve a similar result and this teaches us that we shouldn't make assumptions about animal intelligence or sentience based on whether they are 'built' just like us."

We appear to have made similar mistakes about many species, from bees and birds to primates, partly because of misguided efforts to avoid anthropomorphising them.

Yet human thinking abilities did not simply emerge from nowhere. Their roots extend deep into our evolutionary history, meaning we are likely to share many cognitive traits with numerous other species.

Understanding how other animals think can help us build stronger relationships with them and improve the welfare of the other living creatures with whom we share the planet.

The research was published in Applied Animal Behaviour Science.