Lars Chittka’s book The Mind of a Bee

LArs Chittka recaps his extensive research on bumblebees and honeybees in The Mind of a Bee. Among other things, you get to know the sensory world (the sense of sight in great detail) of the animals, read about impressive cognitive achievements and marvel at old and new knowledge about the structure and function of the brains of these insects. All of this is ultimately brought together to form the question: “Do bees have consciousness and emotions?”

The book thus joins a series of current publications that deal with whether and how we can study the question of consciousness in animals with the prospect of reliable answers. If one follows the approach of the American philosopher Thomas Nagel in his essay “What is it like to be a Bat?” – Chittka calls one chapter “What it’s like to be a bee” – the undertaking must remain hopeless, because science always takes one an external perspective with which the internal perspective of the world of perception cannot be grasped at all.

However, there is a way out that allows at least formal assignments via a list of criteria, which is amazing. If it is agreed that intelligence is shown by the ability to solve problems, to remember things or to adapt, even slime molds are intelligent. They find the shortest way through a labyrinth and can pass on the information they have learned to other animals. Chittka also follows this approach of obtaining answers via a compilation of criteria when he searches for consciousness and emotions in bees. However, he is aware of the risks of his approach: “Of course we are moving in speculative territory.”

Refined experiments in honeycomb construction

If one takes cognitive performance and a certain behavior as a yardstick, one would have to concede to some machines the properties that are reported here for insects. A stricter catalog of criteria includes physiological processes in the brain of living beings. In the spring of 2022, for example, Dhruv Grover and some colleagues published a molecular biological study in the journal “Nature” which states that processes during complex cognitive processes in the brain of fruit flies are similar to those in the brain of mammals.

Thoughts about the “inner life” of insects were made early on by researchers, whose observations and thoughts Chittka presents in detail. These include the Swiss bee researcher François Huber (1750-1831), the American Charles Turner (1867-1923), the Frenchman Jean-Henri Fabre (1823-1915) and the Belgian writer Maurice Maeterlinck (1862-1949). These pioneers were forgotten or were not taken seriously by hard thinking scientists because of their anthropomorphic view. So it is remarkable that the zoologist Karl von Frisch does not mention a single work by Turner, Fabre and Maeterlinck in his book “Dance Language and Orientation of the Bees” (1965). Their experiments were solid and reproducible, but their conclusions about a possible “inner life” of the bees must have seemed far too far-fetched to take the work seriously.

Amazing achievements of bumblebees

Chittka walks on solid ground when describing highly ingeniously conceived experiments in honeycomb construction. However, unlike the book, the building chains are not a phenomenon of unknown function, but an artefact of beekeeping. They do not occur in nests built freely in hollow trees. Chittka’s comments on the recognition of optical stimuli in free-flying bees and on experiments that revealed the cognitive performance of bees and bumblebees are also excellent. The fact that optical stimuli (color, brightness, pattern and so on) can be easily controlled compared to the chemical world of perception makes it understandable that this sensory modality has been processed in previous research with a depth that has to be caught up on for other senses. With better chemical methods that can be used with a high degree of temporal and spatial differentiation, even with free-flying bees, it will be possible to catch up in this field and to answer urgent questions about communication between bees (“dance language”).

The author presents a number of amazing feats of bumblebees, including what he sees as tool use behavior: In one experiment, the insect wants to get at a flower-shaped pad of food. But it is prevented from doing that. The food can only be reached if the bumblebee pulls on a string – which not all, but some do, do with their legs and mouthparts. The behavior is reminiscent of the bumblebee’s efforts to work its way into flowers, but here, since it is prevented from progressing, crawling in place and thus pulling the “flower” towards itself.

What is particularly interesting is that specimens that watched this behavior of their conspecifics were then often able to copy it. You learned through observation. If it is not easy to think about forms of consciousness in bees, the topic “emotions in insects” is even more delicate. Chittka describes experiments that suggest that he believes the bees are capable of expressing emotions (“they might experience some form of emotions”), even if this idea cannot be tested in the sense of Thomas Nagel. The idea is quite engaging. And it would also be useful if it promoted the sustainable protection of these insects.

Lars Chittka: “The Mind of a Bee”. Princeton University Press, Princeton 2022. 272 ​​p., ill., hardcover, €29.99.