I’m sure your kindergarten teacher employed a combination of blocks, M&Ms, and possibly blueberry-scented stickers to instill the value of mathematics in your developing mind. The idea was to pave the way for a future in which you could freely add, subtract, and multiply – in preparation for an age filled with Excel spreadsheets and taxes, of course.
Scientists recently subjected a few underwater animals – cichlids and stingrays – to a similar test, and to their astonishment, the fish passed with flying colors.
The research team claims in a paper published Thursday in the journal Scientific Reports that these animals demonstrated the ability to learn fundamental numbers and even apply this information to solve little logic puzzles provided to them.
“We educated the animals to execute simple sums and subtractions,” said Vera Schluessel, the main author of the study and a member of the Institute of Zoology at the University of Bonn. “As a result, they had to add or subtract one from an original amount.”
What may stingrays and cichlids possibly require these numerical abilities for? On the one hand, the team’s bony cichlid subjects are lively aquarium favorites, mostly concerned with their seaborne nests to the point of becoming hostile and territorial. On the other hand, cartilaginous stingrays lie comfortably on the ocean floor, leading to a solitary existence and threatening prey from afar.
Though the researchers aren’t certain of the explanation, they underline that these findings add to a growing body of evidence showing fish are far more intelligent than we assume and deserve far more respect than we give them.
A very fishy arithmetic puzzle
Here’s what the team’s intelligent fish went through in their rudimentary math education beneath the water. The first step was training.
The scientists first placed each animal in a tank and provided them with an image consisting of one to five squares, circles, and triangles. Though these forms varied in size and were sometimes blended together, they were all either blue or yellow. “Add one” signified “blue.” “Subtract One” means “yellow.”
Schluessel explained, “The animals had to distinguish the number of things depicted while also inferring the calculation rule from their color.” To put it another way, three blue squares equaled “3+1.”
After each animal had memorized their image, they were given two new ones. Imagine that one has one fewer shape and two have one more shape. The animal had to swim over to the corresponding second image based on the color and number of shapes in the subject’s initial image.
Here’s an example.
Assume a stingray was initially shown four yellow shapes. That’s the same as asking them, “What’s 4-1?” When the stingray receives the two new photos, it should swim to the one with three forms. When you think about it, this isn’t a particularly simple task. “When the original photo was exchanged for the two outcome pictures, they had to store both in working memory. And then they had to decide on the correct outcome “Schlussel explained. “Overall, it’s an achievement that necessitates complicated cognitive abilities.”
Every time the animal subjects correctly answered the question, they were given a small treat. According to the study, six cichlids and four stingrays rose to the top of their respective classes over time. They learned the rules – and they learned them well, albeit subtraction was a little more difficult for both species. But that’s natural; I’m sure most others feel the same way.
It’s test time!
It was time for a test after the training period was completed.
The scientists sought to ensure that these animals were not simply being trained to associate a tasty reward with certain visuals, but that they had genuinely internalized how to add and subtract. “During training, we purposefully skipped some calculations,” Schluessel revealed. “3+1 and 3-1, to be exact. The animals saw these two tasks for the first time after the learning period. Even in those examinations, they chose the correct answer more than half of the time.”
Later, after complicating the tests even more by showing a second image with two shapes instead of simply one, for example, the researchers discovered that the animals still chose the correct response – for the most part.
Though the team’s latest study results aren’t particularly surprising, given fish had previously been proven to discern between numerical values, the researchers found it surprising that these animals could use intricate tactics like arithmetic to modify quantities in their minds.
This is because they lack a cerebral cortex, or the region of the brain designed to do complex cognitive activities, as we and other vertebrates do. As a result, it’s very astonishing that the two investigated species demonstrate a similar mental process to us in the absence of the tool. Furthermore, the team’s approach was based on a process previously utilized on honeybees, which resulted in the buzzers successfully calculating values despite a lack of cerebral brain.
“Given that honeybees and humans are separated by almost 400 million years of evolution,” the bee study’s authors write in a 2019 report published in Science Advances, “our findings suggest that advanced numerical cognition may be more accessible to nonhuman species than previously assumed.”
If anything, this merely goes to show that animals don’t have to be anything like humans in order for us to consider them clever and deserving of humane treatment.