Are insects conscious?

For a long time, insects were portrayed as tiny biological automatons. They were thought to react to the world through simple, programmed reflexes, without feelings, experiences, or conscious decisions. Today, that view is beginning to change. Scientists are not claiming that a bee thinks like a human or possesses a complex awareness of its own existence. They are asking something much more fundamental: can an insect have subjective experiences? Can touch, warmth, smell, or injury be felt by it in some way, rather than merely being processed automatically by the nervous system?

Some of the most interesting findings have come from studies on bumblebees. In an experiment published in the journal Science, the insects received an unexpected reward in the form of a sweet solution and were then asked to assess an ambiguous stimulus. Bumblebees that had previously received the reward were more likely to approach the uncertain situation in an “optimistic” way. The effect depended on dopamine, a chemical that also plays a role in regulating emotional states in other animals. The authors described this as a positive emotion-like state, not as proof of human-like joy. The result does, however, suggest that previous experience can change the way an insect interprets later events.

Another important experiment focused on bumblebees’ responses to harmfully high temperatures. The insects could choose between a cooler feeder containing a less sweet solution and a heated feeder offering a better reward. Bumblebees sometimes tolerated the unpleasant heat when the nutritional benefit was sufficiently high. This means that their response to a potentially harmful stimulus was not entirely automatic. The insects weighed the threat against the value of the reward and adjusted their decision flexibly. Such a motivational trade-off is one of the criteria considered in research into the possibility of pain perception, although it does not prove pain on its own.

Researchers also analyze the structure of the insect nervous system. Insects have receptors that detect damaging stimuli, as well as neural connections that allow the brain to influence defensive responses carried out by the rest of the nervous system. This so-called descending control of nociception may allow the animal to weaken or strengthen its response depending on the situation—for example, to continue obtaining food despite a threat or to stop what it is doing and escape. Similar mechanisms in vertebrates are associated with pain modulation, but we cannot assume that they represent exactly the same kind of experience in insects.

In 2024, a group of researchers studying animal consciousness published the New York Declaration on Animal Consciousness. Its authors stated that there is a realistic possibility of conscious experience in, among others, insects. They did not declare that insects are unquestionably conscious. Instead, they emphasized that the available evidence is serious enough that this possibility should not be dismissed simply because an insect brain is small and looks different from ours. The declaration refers to consciousness in a basic sense: the capacity to have experiences that can be pleasant or unpleasant.

The most honest answer, then, is this: we do not know whether insects are conscious, but we can no longer treat them merely as simple machines. They can learn, remember, make flexible decisions, and change their behavior under the influence of previous experiences. They also show responses that meet some of the scientific criteria considered when assessing the possibility of pain and emotion-like states. This is not definitive proof of consciousness. It is, however, enough reason to continue researching the subject and to think more carefully about how we treat the small creatures whose inner world may be richer than we once assumed.