It has been always considered that only those animals who have a complex nervous system can perform logical reasoning. However, researchers have found out that wasps can use logical deduction in their lives which makes them the first kind of invertebrates to do so. The study was published in the Royal Society Biology Letters journal.
The nature of reasoning is known as transitive inference and is performed by human beings easily. An example of it is to ascertain that A is greater than C if A is greater than B and B is greater than C.
Elizabeth Tibbetts, University of Michigan and the team of researchers took 40 paper wasps and placed them in a rectangular jar. Five colours corresponding to letters from A to E were used at different ends.
In the combinations, the colour which matched with the greater letter in the alphabet was assigned to give the wasps a shock if they stood on it.
In the beginning, the wasps were tested with the letters next to each other i.e A and B, B and C, C and D, D and E.
After a total of 10 trials were done, they were tested against the combinations B and D, A and E. So here they would have to use some logic to pass the test.
In total, around 65 percent of wasps were able to choose the correct option which is B over D. A quite similar amount also chose A over E, however, it had a lesser significance since in any combination A would never give shocks while E would always provide shocks.
Scientists think this quality may be present in the wasps due to the social structures in which they operate. Tibbetts commented that the wasps spend a lot of time in fights regarding the dominant rank and for that transitive inference is highly needed.
A similar test was performed with the honeybees but they failed to display such thinking processes. It may be due to the reason that honeybees do not have such hierarchies.
Tibbetts pointed out that even though the final conclusion of the logic is the same in wasps as it is in human beings, but the way the logic works might turn out to be different. It is true that for such conclusions, we humans use logic but as it is tested more in different animals, it is quite difficult to assume that they also use the same mechanisms as humans.
The learning in insects is relatively quick but they only manage to reach a modest level of performance.