Do bees just like the taste of nectar? Does the ant foraging on your crumbs feel higher when she finds one?
Are insects merely tiny robots? Or, within the phrase popularised by the philosopher Thomas Nagel, is there to be a bee?
Until recently, most scientists and philosophers would have laughed on the query. But now, research is difficult that dismissive attitude towards invertebrate consciousness.
It is value clarifying what we mean after we speak about insect consciousness, for the reason that term consciousness carries loads of baggage. Everyone agrees that bees can absorb environmental information and perform impressive computations on it.
We need to know something more: whether insects can feel and sense the environment from a first-person perspective. In philosophical jargon, this is typically called “phenomenal consciousness”.
Rocks, plants and robots don’t have this. Metaphorically speaking, they’re dark inside. Conversely, most of us think that a dog running for its dinner isn’t just somewhat guided missile. It smells its food, desires to eat and sees the world around it because it runs.
Each of those a certain technique to us, and so they feel like something for the dog too. If that is correct, then dogs are conscious, not less than within the minimal sense.
Consciousness is typically used to consult with a rather more complicated capability: the flexibility to . That is a rare achievement. Humans may be the one animals that may turn out to be aware that they’re aware. Even then, we’re mostly just conscious within the more minimal sense, rarely pausing for true self-reflection.
The structure of consciousness
The consciousness of others is a thorny philosophical problem. Our typical handle on consciousness is thru observing behaviour. We think babies and dogs feel hungry, partially because they act like we do after we feel hungry.
Behavioural analogies turn out to be harder after we consider animals corresponding to insects, which don’t look or act very similar to us. We might say that a bee is offended after we disturb its hive. But an offended bee doesn’t act very similar to an offended toddler, so it’s easy to stay sceptical. Behaviour alone actually doesn’t prove that any animal is conscious.
An emerging approach to animal consciousness offers a way forward. Rather than moving from behaviour back to experience, this latest approach moves on to the neural underpinnings of consciousness.
Even if insect behaviour could be very unlike our own, there could be essential similarities between their brains and ours. On this latest approach, we will thus ask whether the insect brain has the structures that might support a basic capability for any type of consciousness.
Neuroscientist Björn Merker has argued that the capability for awareness in humans will depend on structures within the midbrain alone.
The midbrain is the evolutionarily ancient neural core that our enormous neocortex surrounds like a thick rind. Self-awareness requires our evolutionarily young neocortex, but awareness is supported by the simpler and evolutionarily much older midbrain.
Why is the midbrain so essential? Once animals began moving around of their environment, that they had to make a decision where to go next. Deciding efficiently requires combining many various sources of data right into a single neural model with a single perspective on the world.
Tying together knowledge, desire and perception on this integration is the beginning of a first-person perspective on the world, and thus the origin of conscious experience.
r reeve/Flickr, CC BY-NC-ND
What it’s like
While insect brains are minute – the most important are far smaller than a grain of rice – latest research has shown that they perform the identical ancient functions because the human midbrain.
The insect central complex ties together memory, homeostatic needs and perception in the identical integrated way. This integration has the identical function as well: to enable effective motion selection.
In the bee, this detailed representation of the animal in space is what allows it to perform remarkable feats of navigation. Thus, while insect brains and human brains couldn’t look more different, they’ve structures that do the identical thing, for a similar reason and so support the identical type of first-person perspective.
That is robust reason to think that insects and other invertebrates are conscious. Their experience of the world just isn’t as wealthy or as detailed as our experience – our big neocortex adds something to life! But it still looks like something to be a bee.
If this argument is correct, studying insects is a strong technique to study basic types of consciousness. The honeybee brain has lower than one million neurons, which is roughly five orders of magnitude fewer than a human. That is quite a bit easier to review.
Completely mapping the insect nervous system is inside the realm of current technology. Several labs are already working on it.
Once we map the insect nervous system, we will emulate it to check theories of computational function. Initiatives corresponding to The Green Brain Project have already used existing knowledge to start constructing a biologically-inspired drone that behaves like a honeybee in complex environments.
Studying invertebrate experience also opens the potential for studying how and why conscious experience evolved. Our research suggests the tantalising possibility that consciousness has evolved – and been lost – multiple times across evolutionary history.
One essential driver of this process is mobility within the environment. Parasitic worms which have lost their ability to freely navigate have also lost the brain structures chargeable for the first-person perspective.
This suggests a detailed relationship between consciousness and the demands of moving around the globe. By clarifying the environmental demands that press animals to evolve the capability for consciousness, we would thus make clear the connection between subjectivity and the external world.
Invertebrates have long been missed within the study of consciousness. The time has come to take them seriously as a scientific and philosophical model for the evolution of subjective experience.