Honeybees can calculate probability, but it seems they don’t use it the same way we tend to.

Andrew Barron at Macquarie University in Sydney, Australia, and his colleagues trained 20 honeybees to associate the colours of artificial flowers with the likelihood of obtaining sweet water. Over multiple sessions, they presented the bees with five colours in various combinations of two colours at a time. Each colour was ranked one to five. For each pair, only the higher-ranking colour dispensed sweetened water.

The researchers then tested the bees on a combination they hadn’t seen yet: the second and fourth-ranking colours, representing odds of getting sweetened water of 66 and 33 per cent, respectively.

You might think the best strategy for obtaining the treat would be to only visit flowers with the highest odds of delivering, but the bees did something different, says Barron. They matched the proportion of visits with the probability of getting sweet water, so for flowers with 66 per cent odds of sugar, they visited them roughly two-thirds of the time. This is known as probability matching.