Do Insects Experience Consciousness? New Research Explores the Possibility
Researchers in the School of Biological and Behavioural Sciences examine whether insects might possess elements of subjective experience.
Consciousness, the ability to feel, perceive, and be aware, is often considered a hallmark of complex brains. But could creatures with tiny nervous systems, like bees and fruit flies, share some of these traits? A new review by researchers in our school argues that insects may offer critical insights into the evolutionary origins of consciousness.
The paper, published in Philosophical Transactions B (The Royal Society), surveys over a century of research and recent discoveries in insect cognition. While formal proof of consciousness in insects remains elusive, even in humans, the neural basis of consciousness is debated, the evidence suggests that insects exhibit behaviours and brain processes that make subjective experience plausible.
Building Blocks of Consciousness
The authors focus on five key domains: emotion-like states, selfhood, prediction, attention, and sleep.
- Emotion-like states: Insects display responses that resemble emotional reactions in mammals. Bumblebees show optimism-like behaviour after unexpected rewards, and fruit flies deprived of mating opportunities seek out alcohol. Bees even engage in play-like activities, rolling small balls without any reward, suggesting intrinsic enjoyment.
- Selfhood: Experiments indicate that insects may distinguish self from other. Bumblebees adjust flight paths based on their own body size, and some ants exhibit rescue behaviours that require understanding another individual’s body dimensions. Honeybees have also demonstrated metacognition, the ability to assess their own uncertainty, by opting out of difficult tasks.
- Prediction and attention: Rather than passively reacting to stimuli, insects actively predict and focus on relevant information. Bees trained to recognize certain flowers can ignore distractions, and oscillatory brain activity patterns linked to attention in humans also appear in insect brains.
- Sleep and consciousness: Like humans, insects experience distinct sleep phases. Active sleep in flies and bees may help refine internal models of the world, supporting memory and flexible behavior, functions associated with consciousness in mammals.
Why It Matters
If insects possess even rudimentary forms of consciousness, this challenges long-held assumptions about the link between brain size and awareness. It also raises ethical questions about insect welfare and offers a natural laboratory for studying the minimal neural requirements for subjective experience.
As the authors conclude:
“Evidence from all the lines of investigation summarized here builds up to an increasing probability that insects might possess some form of subjective experience.”
Understanding these building blocks could illuminate how consciousness evolved and inspire new approaches in neuroscience and artificial intelligence.