Honey bees may have small brains – containing fewer than a million neurons compared to our 86 billion – but that doesn’t mean they aren’t capable of sophisticated thought. Past research has indicated that the insects can make collective decisions, communicate complex information to one another, interpret patterns, and even navigate to and from their colonies by counting landmarks.
And according to a new investigation published in Science, we can also add them to the very short list of animals that understand the abstract notion of zero.
"Zero is a difficult concept to understand and a mathematical skill that doesn't come easily – it takes children a few years to learn," said study leader Adrian Dyer, of RMIT University, Melbourne, in a statement. In their paper, Dyer and his colleagues explain how the ‘discovery’ of zero by ancient human societies, and its subsequent integration into their mathematical systems, was a critical step forward in our intellectual evolution.
"We've long believed only humans had the intelligence to get the concept, but recent research has shown monkeys and birds have the brains for it as well. What we haven't known – until now – is whether insects can also understand zero."
To test the bees’ capability, the Australian research unit set up a rather ingenious experiment. First author Scarlett Howard began by luring individual members of a bee group to a wall where several paper cards were hanging. Through repetition, she trained them to understand that a sugar water meal would be located under the card bearing the fewest symbols – a feat that is within their known cognitive ability.
"They could come and see two circles versus three circles, or four triangles versus one triangle, or something like that,” Howard told NPR.
After they had mastered that task by consistently flying toward the card with the least symbols, Howard added a blank card into the mix.