Of Eyes & Bats

Our eyes are quite literally our lens to the world, shaping not only how we see the world around us but also how we form our thoughts, beliefs, and reactions to life. For people who have grown up with functional eyes, living a life without sight would be unbearable. The thought of going through the rest of your days without seeing the faces of loved ones, nature and colour is by no means pleasant. We shape our reality primarily on the basis of what we see. But the question is, ‘Is what we see actually all that is there?’. Even though we consider what we see to be absolute, what we can perceive is actually but a piece of the puzzle.

The eye relies on visible light, which doesn’t have the caliber to reveal the arrangement of atoms or the vast empty spaces between them. This limitation raises questions about the completeness of the knowledge it provides. Optical illusions further highlight that the eye can sometimes mislead us, emphasizing the need for additional ways of knowing to supplement sensory data.Now that we have established that our eyes sense things through colour, we can further examine the intricacies behind this elaborate process of seeing colour. Our eyes perceive colour through photoreceptor cells, these cells are responsible for perceiving colour from the light that enters the lens in our eyes. Humans are trichromats, meaning we have 3 photoreceptor cells. This renders our eyes capable of perceiving 3 specific wavelengths, that are red, blue and green. Hence, our eyes only detect a limited range of wavelengths (approximately 380nm to 740nm). This is what we call the ‘visible light spectrum’. However our environment has much more electromagnetic radiation that our human eyes are unable to see. This is not so much the case with other animals such as the mantis shrimp, however. The vision of the mantis shrimp is a true spectacle of biology (pun intended). Their vision is far more complex than ours. They have 16 photoreceptor cells, more than 5x the number of photoreceptor cells in humans. This not only allows them to see much finer colours but also to see colour outside the visible spectrum of light including UV (ultraviolet) radiation and polarized light which helps them in hunting and even in mating.

The bat’s way of interpreting the world is diametrically opposed to that of humans. In fact, bats cannot ‘see’ the world at all. Unlike humans, who depend heavily on vision and more specifically the presence of light, many species of bats (such as the common pipistrelle) use echolocation to navigate and hunt. They emit high frequency waves and navigate by making a mental map of the surroundings via the echoes from the emitted frequencies.  This sensory adaptation challenges the assumption that sight is the most reliable way to understand the world. For bats, their auditory perception provides a richer, more accurate understanding of their environment than vision would. This highlights that different animals rely on different senses to gather knowledge. This also suggests that the pillars that we build our perception on are not universal let alone absolute. What I would see and a bat would see, would both be equally rich and correct in their own way, the bat’s vision would be more spatial while mine would be cognizant of colour. 

Understanding the vision of humans and bats forces us to consider how the knowledge we gain through our senses is not universally applicable. While sight provides us with an immediate understanding of the macroscopic world, the bat's ability to navigate in complete darkness through sound demonstrates that  different organisms have their own method of interpreting their universe and making meaning out of their senses. Both my objects explore the reconciliation of conflicting knowledge by acknowledging that while sense perception is foundational, it is not absolute. Science, through the study of animals like bats helps us to extend our understanding and see beyond the limitations of our eyes. Ultimately the example of the eye and the bat provide a cogent explanation that what we perceive is what is relevant to us, i.e. for the bat, a nocturnal animal, it has to hunt at night and it would need a way to see in the dark which is why it has made these adaptations over a long span of time. According to me, these visions of humans, bats and mantis shrimps are different ways to perceive the same thing, each with relevance to the particular animal. In a way, they complement each other and illustrate that understanding diverging perspectives is where the key to the search for the absolute truth lies.