A New Experiment Shows Bees Can Understand a Symbolic Language For Mathematics
Do you need another reason to love bees? Not only can our fuzzy little flower friends perform basic arithmetic, scientists have now discovered that they can recognize symbols associated with numbers.
Just as we humans recognize the symbol 7 or VII is associated with a quantity of seven, it seems that bees can make the same association.
In other words, they don't just understand quantities, addition, and subtraction - bees can also comprehend a symbolic language for those concepts. That is pretty amazing for a creature with a bee-sized brain!
"We take it for granted once we've learned our numbers as children, but being able to recognise what '4' represents actually requires a sophisticated level of cognitive ability," said vision scientist Adrian Dyer of RMIT University in Australia.
"Studies have shown primates and birds can also learn to link symbols with numbers, but this is the first time we've seen this in insects."
The researchers already had an inkling this was possible. They had discovered, through careful experimentation, that bees seem to understand symbols for addition and subtraction to perform very basic arithmetic.
And we know, based on previous studies, that bees can communicate, using a complex 'waggle dance' to convey information about where to forage.
But this new research takes it a step further, showing, for the first time, that - like humans, chimps and even pigeons have been shown to do - invertebrates can understand and use a language for mathematics.
The researchers employed a modified system previously used to determine that pigeons could recognise numerical symbols. Invented symbols, or 'signs', were assigned a numerosity and placed in a Y-shaped maze.
Bees were trained to fly in this maze, where first they would view a stimulus - either a sign, or an image showing two or three shapes - before nipping over to the decision chamber. There, they would view two options.
If they were shown a sign initially, the two options would be an image of two shapes and an image of three shapes, and they would have to choose the correct number of shapes to match the sign. If they were shown a number of shapes initially, the two options would be two different signs, and they'd have to match the sign to the number of items they viewed.
If they chose correctly, matching an N-shaped sign to two items and an upside-down T to three items, the bee would be given a delicious sugar solution. An incorrect answer, however, would yield harmless, but icky-tasting, quinine.
By the end of the 50 trials, the bees were eventually correctly matching signs to numerosity with an accuracy of around 75 percent. Then the researchers switched it up, testing the bees with new colours, patterns and shapes, to determine whether the bees were matching numerosity to the symbol, and not the image as a whole.
The bees still matched the symbols based on the number of shapes in the image.
But they weren't able to learn the task in reverse. If their training stimulus had been a sign, they were unable to learn again from a numerosity stimulus, and vice versa.
"This suggests that number processing and understanding of symbols happens in different regions in bee brains, similar to the way separate processing happens in the human brain," said zoologist Scarlett Howard of the Université Toulouse III - Paul Sabatier.
"Our results show honeybees are not at the same level as the animals that have been able to learn symbols as numbers and perform complex tasks."
Nor does the research show that bees can comprehend the quantity itself - just that they are able to match a quantity to a symbol, and that they are unable to learn that matching in reverse.
Not only does this help us understand learning, and how the brain builds connections between concepts, but it could lay the foundations of a previously unknown bridge in communications between humans and bees.
"Humans have over 86 billion neurons in our brains, bees have less than a million, and we're separated by over 600 million years of evolution," Dyer said.
"But if bees have the capacity to learn something as complex as a human-made symbolic language, this opens up exciting new pathways for future communication across species."
The research has been published in Proceedings of the Royal Society B.
Honey bees are a great study system to learn about the animal kingdom. They dance (albeit sloppily), they make jelly that turns their larvae into queens, they have crazy tongues … I could go on. Now, researchers have found, honeybees can add.
In a paper out today in Science Advances, a team led by Adrian Dyer at RMIT University in Melbourne put the honey-makers’ arithmetic skills to the test. Instead of written numbers and symbols, they used colors to communicate with the bees. Blue for addition, yellow for subtraction, and a series of shapes to denote the numbers.
They put each honeybee in a Y-shaped maze, where they’d be shown one to five shapes that were either blue or yellow. If the shapes were blue, they needed to fly toward the picture containing one additional shape. If the shapes were yellow, they needed to pick the choice with one fewer shape.
But the bees could still be simply picking the correct answer based on whether it had more or less of the shapes. So, the researchers sometimes made the incorrect choice more, and sometimes less than the correct choice. This ensured the bees had to properly add and subtract to get the answer right.
They trained the bees using a reward-punishment system: sweet sugar solution was a reward for right answers, and a solution of bitter-tasting quinine was punishment for wrong answers. They also mixed up the shapes themselves, their sizes, and which side of the maze held the correct answers, to be sure the bees weren’t picking up on some other clues besides quantity.
Honeybees Can Add
After 100 trials using 14 different bees, the bees’ success rate was around 60 to 75 percent. Perhaps not A+ students; but it’s a passing grade. More importantly, it’s statistically significantly higher than it would be if the bees were just flying around randomly — that would be a 50 percent success rate.
Besides being pretty neat, this opens up the idea that members of the animal kingdom have different cognitive capabilities than we once thought.
A number of animals, including honeybees, have been shown to understand concepts like less versus more or right versus left. But being able to learn a symbolic representation of a math equation, and then solve future “equations,” is another level. Only a couple of species have been shown to do any sort of addition and subtraction besides humans: mostly apes, monkeys, birds, and spiders. If honeybees can add, what else can they do?
“(There’s been) a contentious debate about whether to do math-like thinking, you need a human brain and a very advanced culture to enable that,” says Dyer. “We saw that (the honeybees) can do this task which really does inform us that to do basic arithmetic-type operations you don’t need a large brain.”
Dyer says this opens up the question of how different animals might “have a brain which can also keep a count of quantities and do some basic maths to enable their lives.”
Felicity Muth, who also studies bee cognition but was not involved in this work, says “I definitely think it’s novel and exciting research.”
“I think that it makes sense that a lot of animals should be able to tell the difference between small amounts and larger amounts, it makes sense to be able to tell different quantities of food,” says Muth. “But this is definitely more specific … It’d be interesting to know the ecological context in which bees would use this ability.” Muth is a postdoctoral researcher at the University of Nevada Reno.
One light-hearted side effect may be motivating young kids to learn their arithmetic, says Dyer. “Saying something like 1, 2, 3, you can count like a bee — it puts in their minds, well, if a bee can do it, it must be pretty easy, I can do it too.”
Bees can Count from Four to Zero