Most aquarium snails can see as they have eyes. However, their vision is not well developed. Moreover, some snails are blind. Aquarium snails do not rely much on their eyes. They use their sense of touch and smell to navigate towards the food in the tank or to avoid any danger that they sense.
Let’s talk about snail eyes in detail now.
How Do Snails See Through Their Eyes?
Snails belong to the Mollusca phylum of the animal kingdom. It is a lower level in the animal kingdom.
So, most of their organ systems are lacking or not very advanced.
Some organs may be present but may not function as efficiently as they do in higher organisms.
As we progress higher up the animal kingdom, the different organ systems become more sophisticated.
They exhibit advanced functionalities.
However, invertebrates like snails have very primitive and rudimentary organ systems.
These animals are characterized by the heavy shell that they carry on their back.
It serves as a hiding spot from enemies, and it also protects them during unfavorable environmental conditions.
Let us now take a closer look at the eyes of these animals.
Snails have retractable tentacles on the top of their heads. These tentacles carry the eyes.
Hence, they are also known as eyestalks.
In aquatic snails, the eyes are located at the base of the tentacles. Meanwhile, the eyes are at the tentacle tips in land snails.
An important difference between the eyes of land snails and aquatic snails is that land snails can move their eyes around, whereas aquatic snails cannot.
In water snails, the eyes are locked in place, and it offers a smaller vision range.
In most aquatic snails, the eyes are very basic light-sensitive structures.
They do not offer a clear view or details of what is in the vision frame.
However, it allows them to differentiate between light and shadow. So, the eyesight is limited and not very reliable.
Interestingly, each eyestalk can move independently. It will also regrow if lost.
Studies show that if the tentacles are cut up to mid-length, they can regrow to the original size.
However, the regenerated eye may not have sight.
Some species of snails, like ground snails, are completely blind.
Some others have very underdeveloped eyes. Despite the lack of vision, these snails survive in the wild.
It is because snails do not usually rely on their vision for their important life activities.
They do not depend on sight to locate prey or notice predators.
Their visual ability is mostly limited to sensing light and shapes.
So, they use it to avoid large obstacles and crawl around them.
Their vision is not developed enough to understand the details of the objects.
Even snails with eyes rely on their chemosensory organs to navigate.
They depend on their sense of touch and smell to move around, find food or mates, and escape danger.
Snails also have light-sensitive cells distributed over their body.
These cells help the snails recognize when they are in a shadow.
Now, the presence of a shadow usually indicates the appearance of a bigger predatorial creature.
It signals danger. When the snail experiences this sudden change in light, it will quickly withdraw into the shell as a protective mechanism.
This ability helps the animal to avert danger and stay safe.
Factors That Affect The Vision Of A Snail
The quality of vision will vary from one snail species to another.
Some aquatic snails only differentiate between light and dark conditions.
Others have better eyesight and can make out prey.
The eyes of snails with minimal eyesight resemble pinhole cameras.
Others have vesicular eyes with more advanced functionality.
You can analyze the visual ability of a snail by looking at its dietary habits.
In general, herbivorous snails have a basic eye structure.
However, carnivorous snails have a more developed sense of vision. It helps them locate and hunt their prey.
How Do Snails Navigate Their Way?
We just saw that snails do not have good eyesight. So, it is unlikely that they use their eyes to find their way.
Snails do not have a good sense of hearing. They are almost completely deaf and cannot rely on this sense to stay safe.
Nonetheless, these animals tend to reach everywhere. They find what they need to survive without much difficulty.
Most aquarium snails also display quick reflexes and withdraw into their shells at the slightest hint of danger.
So, how do they manage so much without seeing or hearing well?
It is because the rest of their senses are highly developed. It compensates for their lack of hearing and eyesight.
Did you know that snails can smell very well? The tentacles on the top of the snail have olfactory neurons.
They use these smell and taste receptors to find their way towards food or out of danger.
The accurate sense of smell also helps snails recognize the slime trails of other snails.
Carnivorous snails use this sense of smell to identify the slime trails of their prey.
By banking on this efficient sense of smell, snails find everything they want and use it to their benefit.
Aquarium snails also have a good sense of touch.
They can pick physical vibrations or any other changes in the surrounding water or substrate.
They use their tentacles like feelers, touching and finding their way towards or away from different things in their surroundings.
How Do Snails Find Their Mates?
Despite their poorly developed sense of sight and hearing, most aquatic snails breed profusely.
Even species of snails that aren’t hermaphrodites are able to locate suitable mates.
It makes one wonder how these creatures manage to find their mates in an aquatic environment.
Once again, they primarily rely on their sense of smell and touch for the task.
Aquarium snails can sense the presence of chemicals that indicate the presence of other snails in their surroundings.
They will use their strong sense of smell and tactile receptacles to find their way towards a potential mate.
Related Questions
What happens if an aquarium snail loses its eye? The chances of an aquarium snail losing an eye are very remote. Nonetheless, if it ever happens, it does not usually kill the snail because the eye does not play a significant role in a snail’s life. If a snail loses an eye, it will seal the cut end. Although it can be a disadvantage, most snails manage to survive. Some snails even regenerate their eyestalk if cut.
Do mystery snails have eyes? Mystery snails are commonly kept as pets in home aquariums. These beautiful creatures have eyes on the tip of their tentacles or eyestalks. You can easily recognize the eyes as there are orange rings around the eyes. These orange accents accentuate the black eye dot and highlight its presence. The vision is poorly developed in these creatures. They rely more on their chemosensory abilities to survive.
I had a big ole snail in a tank when I was a teenager named Leroy. I think he could see just fine . When feeding time came he would see me and my hand . He would race to the top of the tank , as fast as a snail can race and eat from my fingers.