Blindness and animals
Are there blind animals? How do they survive?
Talking about blindness and low vision, one might automatically think of only humans. What about animals, though? Visual impairment is not uncommon among animals, either that is merely terrible vision or total blindness. You might have heard that dogs are colorblind, which is actually not true simply because dogs have a much more limited color spectrum than humans, but you surely have also heard about blind dogs. This article will look into animals that are naturally blind, animals that have naturally very bad vision, and animals that go blind throughout their lives.
Interestingly enough, in our versatile animal kingdom, there are multiple animals that are born blind. One of them is the eyeless shrimp, which only has light perception. Another one is the star-nosed mole, the fastest-eating mammal in the world, who uses touch as their main sensory organ. The olm, the blind cave salamander that looks like a baby dragon, is another naturally blind animal, which can yet perceive light through its hidden eyes and skin. There is an extensive list of naturally blind animals, which we will not include here to save you some valuable reading time, but what’s magical is how these animals came to the point to be naturally blind. Darwin’s theory of Evolution by Natural Selection could rationalize why these species have become blind; using vision less than other senses due to the environmental conditions has led their species to, eventually, become blind. The episode “Caves” from BBC One’s documentary called Planet Earth, has some interesting insights regarding blind animals in caves.
Apart from the totally blind animals there are some species that, although they have their sight, it yet works terribly for them. One of them is the bat, who in contrast to common belief, is not totally blind. Bats have terrible vision and this is why they depend on echolocation to navigate and catch food. Bulls belong in the same category, although there is the misconception that they are attracted by red color. In reality, they simply are attracted by anything that moves. Rhinoceroses have really bad vision as well, since they could not tell if there’s a human or a tree in front of them unless they smell and hear them. The list goes on. Perhaps, some of these animals have terrible vision due to, once again, Darwin’s theory of Evolution by Natural Selection.
Last, is the category of animals that become blind later on in life. Cats and dogs can become blind by old age, just like humans. They might also lose their sight earlier in their life due to blindness related diseases, but the real question is how do they survive? Luckily, sight is not the main sensory organ of, at least, cats and dogs, making their blindness a bit less severe. Blind pets need to learn how to navigate when blind or visually impaired, though they still might bump here and there sometimes. Human innovation has come up with this accessory which helps dogs avoid bumping into walls! Perhaps one day, there will be plenty of technologies assisting visually impaired animals.
Overall, nature illustrates that there is not one standard of existence. Some animals might be blind but they certainly have developed other capabilities that have contributed to the evolution of their species. Considering that 80% of visual impairment today could have been avoided with regular check-ups and treatment, could we think that our species might adapt in such conditions? In either way, innovations in the medical technology field would have the answer with the bionic eye or technologies of science fiction.