Stress, optimism, fun. These words seem more suitable to describe the inner life of a human being than that of an insect. And yet, thanks to studies of the neuroethics (the discipline that investigates the neural basis of behavior and its moral implications) we are discovering how much richer the minds of bees and flies are than we thought.
Bees that they choose to play with wooden marbles, even in the absence of rewards. Flies that alternate REM sleep phases, just like us. Evidence of a consciousness much older and more widespread than we thought. But if insects so different from us can suffer, rejoice, have preferences…what obligations do we have towards them? Neuroethics opens a new frontier of philosophical reflection with enormous practical consequences.
A world hidden in the head of a fly
A fly is immobilized in a small block of metal cooled to 2°C. With steady hands and the aid of a microscope, the researcher Dinis Gokaydin gently opens the back of the insect's head to insert a tiny electrode. We are in the professor's laboratory Bruno van Swinderen at the University of Queensland, Australia, where they are studying the secrets of fruit fly consciousness (Drosophila melanogaster).
The goal? To record the insect's brain activity as it reacts to unexpected light stimuli. A crucial experiment for understanding how attention works in flies and, potentially, shed light on the evolutionary origins of consciousness.
Van Swinderen and his team have been investigating attention, sleep, and memory in fruit flies for over a decade. A few years ago, a surprising discovery (I'll link the study here): during sleep, The brains of these insects alternate between active and passive phases, just like REM and non-REM sleep in humans. An unexpected parallel that prompted researchers to wonder whether flies can dream, too.
It's not the only clue that the inner life of insects is richer than we thought.
Using miniature electrodes, neuroscientists record the brain activity of flies as they are exposed to random light patterns. The idea is that unexpected stimuli produce a spike in neural activity, a sign that the insect's attention has been captured. An energy-costly reflex that animals reserve for events that are potentially important for survival.
And it is precisely here that a surprising parallel with human consciousness emerges. For us, too, conscious attention seems to be linked to the ability to react flexibly to new and unexpected situations. When we act automatically, driven by habit, consciousness recedes into the background. But when something unexpected happens, the subjective experience becomes more vivid, ready to guide adaptive responses.
Of course, we don’t know whether flies actually experience something similar to our consciousness. Their tiny brains are very different from ours, and the evolutionary gap between us is huge. But van Swinderen and colleagues’ experiments suggest that some of the “basic ingredients” of conscious life (such as alternating between sleep and wakefulness, or reactivity to the unexpected) may be much older and more widespread than we thought.
A possibility that neuroethics invites us to take seriously, with all its uncomfortable ethical implications.
If even seemingly simple creatures like flies can have some form of subjective experience, perhaps even the capacity for suffering, how should we rethink our relationship with them and the countless other invertebrates that populate the planet?
We do not yet have definitive answers, but the pioneering experiments of van Swinderen and colleagues remind us how vast and unexplored the territory of animal consciousness is. And how urgent it is to map it with scientific rigor and philosophical sensitivity, if we want to build an ethics of the living that is up to the challenges of our time.
Neuroethics of insects, the road to understanding is still long
Many scientists and philosophers remain skeptical that creatures with brains so different from ours could have a subjective life worthy of the name.
One of them is the evolutionary psychologist Nicholas Humphrey, convinced that phenomenal experience (i such as, the subjective sensations of colors, sounds, emotions) is a recent evolutionary achievement, exclusive to mammals and birds. A thesis that has its roots in his pioneering studies on “blindsight” in the 70s.
Observing a monkey with its visual cortex removed, Helen, Humphrey noted that the animal was able to interact with its environment in a surprisingly effective way, despite not appearing to have any visual awareness. A dissociation similar to that observed in humans with “blindsight” following brain damage: an unconscious vision, without the sensation of seeing.
For Humphrey, this suggests that perception and conscious sensation are separate functions, and that the latter is much more recent from an evolutionary point of view. An interpretation that leads him to see the complex behavior of insects as the result of a “robotic consciousness,” devoid of real feelings and sensations.
An open debate, which neuroethics will have to address with theoretical and experimental rigor.
How can we exclude that the “behavioral flexibility” of insects derives “only” from automatisms, however complex? How can we prove that behind it there is a spark of subjective experience, however different from ours?
For now, perhaps, we can't. La consciousness remains one of the great unsolved mysteries of science and philosophy, and the study of minds so different from our own (including the artificial ones) is just beginning. But the challenge of neuroethics is precisely this: push us to explore the boundaries of the possible, to imagine radically “other” forms of subjectivity, to question the ethical implications of this otherness.
Towards an Ethics of Doubt
“As long as there is a non-trivial possibility that a being is conscious, we should give it some moral consideration,” the philosopher repeats. Jeff Sebo, of New York University. A principle that sounds revolutionary, almost subversive. We are used to seeing insects as mechanisms devoid of interiority, as “alien creatures” whose interests (if they have any) count for little or nothing compared to ours.
But what if there was even a slight chance that this wasn't the case? What if behind those mosaic eyes and tiny nerve ganglia lies a glimmer of experience, of well-being, perhaps of suffering? Then our indiscriminate exploitation of these creatures (from scientific research to mass farming, to the use of pesticides that exterminate trillions of them every year) takes on a whole other meaning.
It is a paradigm shift that neuroethics invites us to consider, a “thought of the unthinkable” that shakes deep-rooted beliefs about the presumed exceptionality of humans and the few animals most similar to us. An uncomfortable thought, which if taken seriously would have immense consequences on our habits and our relationship with the biosphere.
This is precisely the task of a philosophy that is up to the challenges of our time: to push us into unexplored territories, to shake our certainties, to imagine new ethical possibilities.
Insects like bees and flies will certainly not stop seeming alien, distant, almost indecipherable. The “empathic gap” that separates us from them remains sidereal. But neuroethical research is beginning to bridge this abyss, to suggest unexpected continuities of the phenomenon of consciousness through the living.
A continuity to be explored with rigor, without hastily projecting our experience onto such different creatures. But also without closing the doors prematurely, entrenching ourselves in the assumption that “true” interior life is an exclusive privilege of a select few. Faced with the immensity of our ignorance on the subject of consciousness, perhaps the only ethical approach is a precautionary principle, a “giving the benefit of the doubt” to the myriads of alien minds with which we cohabit on the planet.
Of course, embracing this doubt is uncomfortable, because it calls into question practices deeply rooted in our way of seeing and treating “lower animals”. Practices that are often brutal and devastating, on a scale that defies imagination: just think to over 70 billion land animals slaughtered every year, or to the estimates according to which by 2100 human activities could cause the extinction of 50% of all insects.
But it is precisely here that neuroethical reflection becomes more urgent and necessary.
The abysmal responsibility that could arise from recognizing the shadow of a conscience in creatures so diverse, and so far so exploited, could force us to radically rethink our way of inhabiting the biosphere, of interacting with the innumerable forms of life that populate it.
We have no definitive evidence that bees and flies, or other invertebrates, are conscious. Maybe we will never have them, given the challenge of probing such alien minds. But we have growing evidence that their inner life is much richer and more complex than we thought. And we have, above all, a moral duty to take seriously the possibility that creatures very different from us may have a well-being to protect, perhaps a subjectivity to respect.
It will be a long, difficult process, full of unknowns and resistance. A process that will require an enormous effort of ethical imagination and practical innovation. But it is one of the great challenges of our time, if we want to build a more harmonious and sustainable relationship with the biosphere on which we depend. And neuroethics, in its intertwining of empirical science and moral thought, is perhaps the best compass we have to orient ourselves in this fascinating, disturbing frontier territory.
