Last Updated on August 15, 2020 by John B. Nelson
A few days ago, I was talking with one of my friends, and he owned a turtle. Suddenly he told me that during the quarantine days, he has been observing his turtle and found a shocking truth. He noticed that it was moving better in water during the dark time than in the light on.
So, it prompted me to see for the answer of, “Can turtles see in the dark?”
And guess what? I was shocked by the answer. Experts said that turtles could see in the dark likewise we humans do.
Since the answer was somewhat unexpected (honestly speaking, I thought turtles couldn’t see in the night), I researched on turtles’ vision and how they can see in the dark. Also, I investigated turtles’ eyesight affectivity during the night time.
So, here’s what I have found.
How Can Turtles See in The Dark
Although turtles can see objects in the dark like humans, there are differences in how they see in the night and how their vision acts. A recent study on the turtle vision and eye receptors found that these animals see objects in a reddish form than we humans do in real life.
For instance, on a bright starry night, the turtle will find the sky on a reddish side, whereas we humans will see it a blue or a bit darky. However, when it comes to seeing during the night in the forest, distinctions aren’t so prominent. It is because, at night, forests are darker than the night sky, and thus, it limits the vision significantly.
This brings us ardently to an important question, do turtles have night vision?
Well, you should get the answer by the time since I have said that in the darkness of the forest, turtles can’t see. So, it implies that they don’t have night vision that actually enables the five big cats to see and hunt in the hide of darkness.
To be honest, turtles’ eyesight isn’t better than humans.
Do Turtles See Immediately in The Dark or Need Adjustment Time?
No, turtles can’t see in the dark immediately. Instead, they need a few moments to get accustomed to the dying light.
Just imagine yourself? Do you see everything in a room instantly after switching off the light? No, unless you are a superhero.
Studies show that humans need 30 seconds to adjust to the darkness and see around. Just like the human, turtles also need some moments to accommodate itself with the darkness. Once they get accustomed to the dark, they can move around the area.
How Do Turtles See in The Colors Around It?
Earlier, we have developed a misconception that turtles were color blind. It implied that they couldn’t see the color variations around them.
But over the period, with numerous scientific researches, now we know that turtles see and identify various colors. However, they do it in a different way than humans. Also, previously many believed that these animals don’t have good vision.
But it isn’t true either, as you have seen in the previous section.
So, let’s focus on the procedure of turtle color seeing capacity. Likewise, humans, turtles, and other animals see colors using the receptors in their eyes. Humans have three receptors in their eyes, and so, they can visualize a wide range of color reception. These receptors are known as Cone.
Nonetheless, studies have shown that turtles and most animals have a bit more receptors or cones than humans. So, it is most likely that they can identify more colors than us.
And the final twist….
Do you remember that I have previously said that turtles see in a reddish format?
If yes, then know that it happens mainly because of the gene called CYP2J19 or ‘redness gene.’ The evolution of the gene is dated back to 250 million years ago. It was first found in a dinosaur, now known as Archosaur.
Since turtles also own the CYP2J19 gene in their receptors, they see a lot more variations of red pallets than a human. It is thus responsible for the turtles’ slightly reddish vision.
How to Verify Whether or Not Turtles Have Night Vision in The Dark?
If you still have the disbelief that turtles can’t see in the dark, here’s a little test that you can do to know the truth.
But before that, you need to understand the term, tapetum lucidum. It refers to the membrane in eyes that sends back the photons in the eyes and enables animals to see in the dark with superior clarity. Thus, it is responsible for the night vision capacity.
You can easily see whether or not a turtle has tapetum lucidum. For this, take the photo of turtles’ eyes from a close range using your phone flash. Usually, animals with night vision, such as cats and dogs, will have a glowing photo of their eyes.
On the contrary, turtle eyes will have no glowing photo of their eyes. It reconfirms the lack of night vision in their eyesight.
Do Turtles See in Underwater?
Now, this is a burning question since turtles live a considerable part of their life underwater. So, let me be straightforward.
Turtle’s vision in the water remains the same as in the land. So, most turtles, especially the sea turtles, can swim at large in underwater.
However, if the water is dirty and lacks light, turtles’ eyesight will reduce significantly. So, when you pet turtles, make sure the pond or tank water isn’t greasy.
You may be interested to know what keeps the turtle eyesight in underwater unaffected, right?
Well, their eyes produce mucus when they are in the water. It forms a protective layer and keeps their eyesight unharmed even in the water. Sometimes, the mucus is mistaken as their tears, but it’s not true. Also, if you notice sea turtles’ eyes full of mucus-like, it is crying, note that it isn’t true either.
Sea turtles put away the excess salts through mucus production that may look like tears sometimes.
As we come in the concluding section of our discussion on can turtles see in the dark, here are some critical keynotes to take from the write-up.
Firstly, the turtle can see in the dark.
Secondly, they see more red color pallets than humans, mainly because of the CYP2J19 or redness genes. Also, they don’t have night vision.
Finally, before I wrap up, let me mention that turtles don’t need light in the night. In fact, lighting at night will hamper their sleep cycle. So, when you turn off the room light, there’s no harm in it for the turtles. They will still move freely within the tank if needed.
Hi, This is John B. Nelson and the author of this website. As a cute pet, I love the turtle very much. Based on my experience with the turtle, I am sharing my opinion about the turtle care and habitat tips on this blog. I think these tips will be helpful to those peoples who have eager to turtle and want to start a journey with the turtle. Find me on Twitter. Happy reading!