New research suggests that honeybees can rank numerical quantities and understand that zero belongs at the lower end of a sequence of numbers.
Adrian Dyer, of RMIT University in Melbourne, Australia, is a co-author of the study, published June 8, 2018, in the peer-reviewed journal Science. He said the number zero was the backbone of modern math and technological advancements. Dyer said:
Zero is a difficult concept to understand and a mathematical skill that doesn’t come easily – it takes children a few years to learn. 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.
Previous research has shown that honeybeees can learn intricate skills from other bees and even understand abstract concepts such as sameness and difference. But bee brains have fewer than 1 million neurons – compared with the 86,000 million neurons of a human brain – and little was known about how insect brains would cope with being tested on such an important numeric skill.
To test the bees, the researchers trained bees to choose an image with the lowest number of elements in order to receive a reward of sugar solution. For example, the bees learned to choose three elements when presented with three vs. four; or two elements when presented with two vs. three. When the researchers periodically tested the bees with an image that contained no elements versus an image that had one or more, the bees understood that the set of zero was the lower number – despite never having been exposed to an “empty set.”
Dyer said the findings opened the door to new understandings of how different brains could represent zero. He said:
This is a tricky neuroscience problem. It is relatively easy for neurons to respond to stimuli such as light or the presence of an object but how do we, or even an insect, understand what nothing is?
How does a brain represent nothing? Could bees and other animals that collect lots of food items, have evolved special neural mechanisms to enable the perception of zero?
If bees can learn such a seemingly advanced math skill that we don’t even find in some ancient human cultures, perhaps this opens the door to considering the mechanism that allows animals and ourselves to understand the concept of nothing.
One of the problems in the development of artificial intelligence is enabling robots to operate in very complex environments, Dyer said.
Crossing a road is simple for adult humans. We understand if there are no approaching cars, no bikes or trams, then it is probably OK to cross. But what is zero, how do we represent this for so many complex object classes to make decisions in complex environments?
If bees can perceive zero with a brain of less than a million neurons, it suggests there are simple efficient ways to teach AI new tricks.
Bottom line: A new study suggests that honeybees can understand the concept of zero.