Here is a question for you. If A is greater than B and B is greater than C, then A is greater than C?
It's a simple puzzle, something that children can solve. In fact, even animals have demonstrated the form of reasoning, called transitive inference, which we use to respond to this type of problem. But no invertebrate has shown this ability, until now.
In new research, scientists suggest that paper wasps can use transitive inference just like you and I, to find out the relationships between various things that have not been explicitly compared to each other, but have been previously compared with other elements .
"We're not saying that wasps used logical deduction to solve this problem, but they seem to use known relationships to make inferences about unknown relationships," says evolutionary biologist Elizabeth Tibbetts of the University of Michigan.
"Our findings suggest that the ability for complex behavior may be determined by the social environment in which the behaviors are beneficial, rather than being strictly limited by the size of the brain."
Polistes dominates. (Elizabeth Tibbetts)
Tibbetts has studied wasps, their behavior and their environment for decades, discovering things like their memory of other wasps from previous encounters, and the ways they have to punish other wasps that are not honest about their condition.
Other research in which she has been involved has discovered how wasps developed a better vision to capture social cues; Now, in the same social vein, Tibbetts suggests that the wasp society may also have developed its reasoning capacity, specifically, the transitive inference.
Similar experiments have already suggested that bees do not possess the same gift, but new experiments with paper wasps Polistes dominula Y Polistes metricus It seems that some insects can infer more astutely than others.
In the experiments, wasps were introduced into a hierarchical color clbadification called "premise pairs". The premise of the pairs was that if the wasps fell in color B instead of color A, they would receive a slight electric shock.
In turn, the same would happen if they landed in C instead of B, D instead of C, or E instead of D. In all cases, the color corresponding to a previous letter was the safe option.
Surprisingly, when wasps were shown colors that had never before been presented in a pair, such as B and D, for example, wasps showed a preference for colors that would not impact them in two thirds of the time.
This demonstrated preference suggests that they could infer a relationship between novel matched elements: combinations of things that had never before been explicitly demonstrated together.
"I was really surprised at how quickly and accurately the wasps learned the premise pairs," says Tibbetts.
"I thought that wasps could get confused, like bees, but they had no problem realizing that a particular color was safe in some situations and not in others."
As to why wasps and paper bees, which share equally complex nervous systems, may have such a different score in terms of their capacity for transitive inference, no one can say for sure.
But researchers think, like many other things in the evolution of wasps, the foundations of reasoning could be in the nature of their social relationships, which are very different from those of bees.
Unlike colonies of bees centered around a single queen, Polistes Wasp colonies have more complex social arrangements, since multiple breeding females called founders compete with each other within a single colony, establishing a range of hierarchies.
Tibbetts and his team say it is simply possible that the pressures resulting from living between the paper wasps and the rival dynasties established by the founders have given insects the ability to make decisions based on social information: infer distinctions and subtle relationships. That a simple bee has never had to pick up.
"Species like Polistes Wasps that have complex social lives can benefit from organizing information in a linear way because this allows individuals to make rapid deductions about novel social relationships, "the researchers explain in their article.
"As a result, socially flexible taxa may be predisposed to spontaneously organize information along a common underlying dimension, as required for transitive inference."
Anyway, that is the approximate idea, although the researchers recognize that it is only a hypothesis for now, until future experiments reveal clearer evidence, so that we ourselves can better infer what is really happening here.
In any case, no matter where they get it from, we know that these wasps know how to join the points in a way that no other insect has proven to do, and that is something extraordinary to see.
The findings are reported in Biology letters.