The body of any creature has multiple body parts and organs which have a specific purpose. Whether it’s a human or an animal, every being has specific body parts that are useful. Eyes are one of the most important body parts and helps us in obtaining the vision which is one of the 5 senses. Yet if a person loses vision, he or she can manage without it. There are many people who are blind and manage to have a good life with the use of their other organs and senses. But did you know that like humans, animals can be blind too.
While it’s rare that an animal becomes blind due to an accident, it is very common for some animals to born with blindness. These animals range from all the different species to the different types of habitat. Unlike humans, it is not a disability for these animals to be born without any vision or eyes. But it is what helps them surviving in the conditions which they live in. It is a well known fact that animals have very strong senses. Which is also the reason for most of these animals’ survival in their natural habitat. So here is a list of animals that don’t have eyes or are blind:
Blind Cave Fish(Mexican Tetra)
There are two types of Mexican Tetras: the ones that can see and the other ones called Blind Cave Fish. How the Blind Cave Fishes went from Mexican Tetras with vision to no eyes is a story of evolution. These fishes live in caves with nearly no source of lighting. In order to save energy due to the food being scarce, these animals have to be sightless. It gives them a big boost in doing so and has helped them survive in these conditions. As per experts, an animal living in complete darkness doesn’t need vision to survive.
Studies have shown that the young fishes can save up to 15% of their energy without the use of eyesight. Scientists were confused to find these same fishes with eyes in Texas and Mexican rivers. But with recent theories, the mystery of these fishes seems to be solved. These fishes are said to be omnivorous which means that they survive on anything they find in the surroundings. While the theory of evolution seems to fit these fishes’ blindness perfectly, it is also suggested that they may grow their eyesight back. There also has been hints of these fishes producing offspring with eyesight.
Texas Blind Salamander
Another animal living in the darkness of underwater is the Texas Blind Salamander. With no need of vision for these amphibians, their eyes have been reduced to black spots. The length of these salamanders is somewhere between 3.5 to 5.5 inches (9 to 14 centimeters). As the name suggests, these are found in the caves of Texas. Since 1967, they have slipped to the list of endangered animals and face the danger of going extinct in the next 100 years. However, the Edwards Aquifer in Hays County, Texas has been taking care of these salamanders.
These can live for more than 5 years and up to 10 years. The females have been seen as the one who initiates the breeding and can reproduce anytime of the year. They can lay up to 35 eggs at a time in suitable conditions which includes a temperature of about 22°C or 72°F. These creatures rarely go to the ground level except when the water pushes them onto it. The Texas Blind Salamanders are known to be the top predators of their habitat. While their diet varies due to the low food sources in the caves, their main diet includes snails and shrimp.
Kiwaidae (Yeti Crabs)
Due to their hairy appearance, these creatures are called Yeti Crabs (in relation to the mythical creature Yeti). These were formerly seen as related to crabs, lobster, and shrimp due to their appearance. But with timely research, it was found that they are quite different from these creatures and were classified differently. This gave birth to a new family called Kiwaidae, named after the Polynesian goddess of shellfish. The discovery of these creatures took place as late as 2005 during the March-April 2005 PAR 5 Research Expedition. In total, there are 4 species that have been distinct to this family.
Males of this family seem to prefer a rather cold condition while the females and juvenile prefer war conditions. These creatures have a small brain as compared to the rest of their body. While little is known about their bodies and functioning, scientists are doing their research on the subject. One of the main mysteries about these creatures is how they use the bacteria. While some suggest that they use the bacteria in their bristles which helps the bacteria reproduce. This in turn may help these creatures in getting carb food and becomes one of the main sources for it.
Caecilians
These strange creatures can look like either worms or snakes due to their range of appearance. Their height ranges from 3.5 inches to nearly 5 feet. While most of the caecilians are blind some have eyes that only detect light or darkness. To help these animals navigate and detect food, they have small tentacles on their face. Living underground or underwater, these creatures have good digging skills which helps them to survive in these habitats. They can be found in many parts of the world from Central and South America to Central Africa and Southeast Asia.
Similar to frogs and salamanders, these creatures lay their eggs in water or under moist soil. A special feature about these creatures is the way the females feed their young ones. The females with young ones have an extra thick skin which the young ones eat off. This behavior in animals is termed as “matriphagy” by scientists and can also be seen in other animals. One can find these creatures in a variety of different skin colors from grey to blue and black. While they live underground, the Ecuadorian ‘Caecilia pachynema’ is known to come onto the ground at night during the torrential rains.
Sea Urchin
A sea urchin is very unusual due to a number of different factors. From its shape to its behavior, this creature is nothing but abnormal. It looks like a porcupine and is in fact called the porcupine of the sea. It belongs to the same group of sea creatures such as sea stars, sand dollars, sea lilies and sea cucumbers. These are found in oceans all around the world except for the colder, polar regions. Their survival rate is very high with the Red Sea urchin being the longest living creature. The Red Sea urchins can live up to 200 years.
These creatures are omnivorous and can survive on both plants and animals. From algae to mussels, dead fish, sponges and barnacles. Apart from them eating other animals, these creatures are also in a list of prey for other predators. These predators include sea animals to birds and humans as well. A sea urchin’s spine can be its most useful body part which may help it in survival. From moving around to protect themselves and sometimes their neck is used to trap the food particles. Today however, the sea urchin’s population is decreasing, and they are facing the danger of extinction.
The Cause of Blindness and Other Blind Creatures
Most of the animals that are blind live in dark atmosphere which makes it useless to have vision. There are also animals who are helped in survival due to their blindness. Apart from the animals, there are many sub species and families of animals that are known or suspected to be blind. Many insects are known to be blind which helps them due to their smaller sizes. Blind mole is one of the few land mammals that is blind. It has a thick skin which covers its eyes and prevents the creature from seeing. This leads the animal to become an easy prey for its predators while it has some instincts to avoid attacks.
Most of the animals who are blind rely heavily on their instincts as well as other senses in order to survive in their habitats. Just like humans, animals can also adapt to the place of their habitat and if it helps them going blind then why not. Researchers are finding more and more of these creatures that can survive in the wild without any vision. While there are many nocturnal creatures like bats which have a questionable eyesight. Some of these creatures can see at night while failing to have vision at day time. This has made them step out at night while stay in during the day. The opposite also happens to some animals who are not able to see or have poor eyesight at night. This condition is termed as “Nyctalopia”.