According to a growing body of scientific evidence, insects such as bees exhibit signs of some form of consciousness. Behavioral studies of corvids, great apes, elephants, and many other birds and mammals suggest that they are likely to possess consciousness. Now, researchers are turning their attention to a broader range of organisms, including invertebrates like octopuses, bees, and flies.
According to recent scientific reports, a group of scientists is reevaluating the relationship between animals and humans. Last month, more than 40 scientists from various fields co-signed a document called the “Cambridge Declaration on Consciousness” aimed at advocating for more research into animal consciousness and supporting it with the necessary funding. Jonathan Birch, a philosopher at the London School of Economics, is one of the main authors of the declaration, and he believes that as we increasingly understand the complex behaviors of animals, the scientific community should begin to acknowledge the possibility of animal consciousness instead of regarding it as an absurd notion.
Although the declaration does not specify which species definitely have consciousness, it emphasizes that there is enough evidence to support the possibility of conscious experiences in some species that are vastly different from humans. This includes reptiles, fish, and insects, which have long been regarded as lacking consciousness, while there is more concrete scientific evidence of consciousness in birds and mammals.
Birch indicates that while the definition of consciousness is quite complex, he and his research team focus on studying one particular aspect—perception. This is defined as the ability to subjectively experience the world around, and for animals, these experiences include senses like smell, taste, hearing, or touch, as well as emotions such as fear, pleasure, or pain.
Since animals cannot verbally express their inner states, scientists must rely on indirect evidence to assess their consciousness. For example, the “mirror test” is a classic experiment used to test whether an animal can recognize itself in a mirror. Animals showing curiosity about markings on their bodies and attempting to remove them suggests that they might possess self-awareness, indicative of conscious experience. The experimental behaviors of animals like crows and octopuses are also potential manifestations of consciousness. Additionally, studies on fruit flies show that they have periods of deep sleep and light sleep, during the latter of which, the brain activity pattern of fruit flies is similar to when they are awake.
Professor Bruno van Swinderen, a biologist who has signed the declaration, mentioned that dreams may be considered a core element of consciousness. If invertebrates like flies have active sleep cycles, it may suggest that they also have some form of consciousness.
There is no consensus in the academic field on whether animals possess consciousness. Even though more and more studies show that animals exhibit complex perceptual behaviors, this does not directly prove that animals have consciousness. Hakwan Lau, a neuroscientist at the RIKEN Brain Science Institute in Japan, points out that there is still no conclusive evidence for the existence of animal consciousness. In the case of humans, we can observe the coexistence of conscious and unconscious perceptions, which makes the question of animal consciousness even more complex and elusive.
Although there is no consensus on the exact nature of animal consciousness, some researchers believe that exploring this issue can still potentially positively impact the creation of animal ethics and welfare policies. Research and discussion of such issues may encourage people to make more humane and responsible choices in their treatment of animals and legal standards.
