Do insects have cognition?
To what extent are insects intelligent? Let's look at experiments on the potential of their minds.
Many animal species have been shown to have cognition and other characteristics traditionally thought to be exclusive to the human species.
Other mammals, birds, reptiles and mollusks such as the octopus are capable of solving relatively complicated tasks, but few seem to consider the possibility that smaller animals are capable of the same.
Do insects have cognition? This is a question that, although more than one might find hilarious, science has been tackling in earnest in recent years. Let's see what they have found...
Do insects have cognition? Experiments to understand their mind
Humans have found similarities in other species in terms of intelligence, emotions, personality and behavior. We have long known that dolphins, birds, dogs, cats, reptiles and, of course, other primates like us have a higher level of understanding than was believed decades ago. We humans have long since come down from the pedestal and abandoned the idea that we are the only ones with cognition.
However, there are still certain prejudices regarding what animals can feel, understand and perceive that, due to their minuscule size and relative simplicity, we would not believe they have anything resembling cognition: insects. Do insects have cognition? Their brains are tiny, with neural networks that are laughable in comparison with those of an animal like a dog, so it is even comical to raise the question of whether insects have cognition.so it is even comical to pose this question as a serious one.
But science does not care what prejudices the average citizen has about flies, bees and mosquitoes. Much research has shown that these arthropods, with or without wings, are capable of learning and teaching, have emotions, goals and expectations. Throughout this article we are going to talk about a few experiments in which several aspects related to the idea of cognition in insects have been tested.
Ants with expectations
In the late 1970s, Daniel Kahneman and Amos Tversky put forward the prospect theory.. This suggests that human beings do not perceive the value of things in absolute terms, but in a relative way and taking something as a referent.
For example, if we go to a bar and they give us orange juice from a brick every time we go there, the day they serve us real freshly squeezed orange juice we will taste great, valuing it much more than another customer who from the first day he went to that bar was served squeezed juice. We will be surprised because our expectations, which were low, have been exceeded.
It seems that the same thing also happens in ants. In their experiment, Stephanie Wendt and colleagues (2019) trained ants with sugar drops of different concentrations. They found that the value that ants attach to a food depends on the expectations they have, which were formed during the training. Thus, if the ants expected to receive a drop with low sugar concentration and received that same drop throughout the experiment, their behavior was unremarkable, moving a little from side to side and occasionally sucking on the drop.
However, the behavior of the ants that were presented with a drop with a higher sugar concentration in the experiment was totally different.. Unlike the previous ants, these ants, which also went to the drop with rather low expectations, upon discovering the delicious delicacy before them, focused fully on the sweet nectar. Concentrated, they did not move a single millimeter and sucked tirelessly, giving themselves a real feast having discovered such a succulent treasure.
- Related article, "Do insects feel pain?"
Bees and caffeinated flowers.
Coffee is that heavenly nectar that many people need to drink as soon as they wake up. This substance helps to awaken our minds and it seems that it does so in bees as well, helping them to remember things better. The study by Sarah Arnold and colleagues (2021) tested to see what happened when bees were given caffeine in the sweet nectar they drank from flowers and whether this influenced their memory.
The scientists already knew that caffeine, which is found naturally in citrus trees and the coffee plant itself, plays a very important role in making bees remember coffee, plays a very important role in making bees frequent consumers of its caffeinated flowers.. Experiments prior to theirs had already found that bees preferred flowers with caffeinated nectar, but it was not known whether this was simply a preference or whether it influenced their recall of flowers containing a sweet reward.
To answer this question, Arnold's team decided to give the bees caffeine when they were near their nest, making them associate the taste of the sweet nectar with the artificial aroma of the strawberry flower. They took 86 bees and divided them into three groups: one in which the bees were given a strawberry scent and a caffeinated sugar solution; a second in which the bees were trained to associate the strawberry scent with the sweet reward, but without the caffeine kick in between; and a third control group that was simply given the sugar solution with no scent and no caffeine.
After the training, the experimenters released the bees into a kind of flying stadium where they had to choose between two types of artificial flowers: some with strawberry scent and some with caffeine scent.The bees had to choose between two types of artificial flowers: one with strawberry essence and the other with other essences that acted as distractor flowers. The hypothesis was that those bees that had not associated the smell of strawberry and nectar would visit the two types of robotic flowers equally.
The researchers found that caffeine had a strong influence on the recall of these hymenopterans. 70.4% of the bees that had been trained with the caffeine shot visited the strawberry-scented flowers first, as opposed to the bees trained with the caffeine shot, which visited the strawberry-scented flowers first.In contrast to the bees trained without the caffeine shot but with the scent, which took the strawberry-scented flowers as their first choice 60% of the time. The bees in the control group, which had been fed only unscented nectar and no caffeine in the process, only 44.8% of them chose to go to the strawberry-scented flowers first.
This experiment suggests that bees learn best by taking caffeine, consciously choosing those flowers that they know bring rewards as they were taught in the training phase.
Bumblebees that learn and teach.
We move on from bees to bumblebees, which some call the "flying teddy bears". Well, not many people call them that, but the researchers in the following case have found out if these insects have the ability to learn and teach their conspecifics.
Bumblebees are animals that seem to have an uncanny ability to come up with new solutions to problems.. Not only that, but if they see a mate nearby, they notice and help it. They do not simply copy what they see or try by trial and error, but are able to adapt what they have observed in order to solve a situation more efficiently, thus showing some creative behavior.
Research from Queen Mary University of London demonstrates this. Its authors, Olli Loukola and colleagues (2017), trained bumblebees to move small balls to the center of a platform in order to get sugar water. The behaviors observed throughout the experiment, according to Loukola, come to demonstrate an amazing cognitive flexibility, as well as a conscious interest in replicating the behavior seen in their conspecifics.
The experiment was conducted with three groups of bumblebees of ten individuals each. The insects in the first group faced the problem for the first time but had a previously trained bumblebee tutor show them what they had to do to get sugar water. The second group consisted of teaching the bumblebees what to do by means of a "phantom" demonstration, in which the researchers moved the ball from the outside with a magnet. In the third group the ball was already in the circle when the insects were introduced into the experimental setting.
What the researchers observed was that the insects that learned through a conspecific had very high success rates, succeeding 99% of the time.. Bumblebees that were trained with the phantom ball were 78% successful, while those that were trained with the ball already in place figured out what to do 34% of the time. This experiment demonstrates that bumblebees are capable of developing new behaviors and consciously teaching them.
Bad smells, good smells and flies.
Finally we leave the case of other winged insects, in this case fruit flies.. A group of researchers from Bristol in 2018 trained flies using two odors associated with two different stimuli. In their experiment, they had the flies learn to associate a positive odor (P) with a sugar-based reward, and a negative odor (N) with an unpleasant vibration. During training, they were exposed to one of these odors and also to a stream of clean air, and it was up to them to choose between one or the other.
Once the flies had been trained, they were separated into two groups. Group A flies were shaken for one minute and group B flies were not shaken at all. After that, they exposed these two groups to the N and P odors, but this time they included a new one, a mixture of both odors that we will call P+N. The flies didn't know whether the P+N odor carried sugar or vibration, since it was the mixture of the two training odors, so they would have to take a chance if they chose it.
The results were revealing. Flies that had been agitated in training did not want to risk it and showed some fear of being agitated again, and they seemed to value less the sweet reward of sugar associated with the P odor.Their behavior was cautious, fearful, pessimistic and implied that they remembered very well that the N odor carried with it an unpleasant sensation.
This experiment indicates that flies, despite their tiny brains, are capable of learning and can also exhibit something similar to learned helplessness. Finding themselves in a situation of doubt, where two stimuli are presented that have been associated with consequences of different signs, makes the flies not quite know what to do. If they had no cognition at all and only behaved instinctively, they would most likely take a risk without further ado.
Final thought
These experiments along with many others have come to demonstrate that insects, in spite of having tiny brains and extremely simple neural circuits, are capable of solving exceedingly difficult tasks.. They recognize visual patterns, memorize the scent of flowers, learn to move levers, balls or even to pull threads.
The cases we have discussed correspond to social insects, which would suggest that few species of these arthropods are capable of exhibiting anything resembling cognition. It makes sense that these particular species are able to learn and teach behaviors to other individuals because the behavior of each of them is determinant for the health of the colony, as in the case of bees.as is the case with bees, ants and other hymenopterans.
However, considering that individualistic insects have brains not much simpler than those of social insects, it would not be at all strange to find these same behaviors in these species. Whether social or individualistic, everything seems to indicate that, yes, insects do have cognition, and more sophisticated than we thought.
(Updated at Apr 12 / 2024)