If you’ve ever spotted an owl in your life, count yourself among the fortunate ones. Very few people can spot an owl in their day-to-day lives, and there’s a good reason behind this. Owls are nocturnal creatures, which means that they’re almost always out and about at night. Moreover, being one of the raptors, they also prefer to be in the wild rather than in the bustling cities and suburbs.
Coming back to point, if you’ve ever seen an owl for longer than a few minutes, you’ll feel deeply unsettled by their gaze. However, rest assured; they’re definitely not an omen for the bad times. Owls have exceptionally large eyes for their body size because they’ve evolved to accommodate their needs.
Read on until the end of this article to learn how different owls’ eyes are from ours and how they work!
Eyeballs or eye tubes: What are owls’ eyes like?
As humans, we possess eyeballs, which means that our eyes resemble the shape of a ball. But are the eyes of the owls shaped just like us? No; on the contrary, their eyes are completely different than ours.
Instead of small, ball-like structures, the owls’ eyes have evolved into tubular structures. If you’re having trouble imagining that, just think of their eyes as binoculars already fitted inside their heads. Large bone structures in the owls’ heads hold those eye tubes in place, called sclerotic rings.
In addition to having eye tubes, the owls’ eyes are quite large for their bodies, giving them a constantly bewildered look. This is also why they look scary and unapproachable, while in reality, they just can’t help it.
How do the eye tubes help owls’ vision?
Although it might seem quite disadvantageous to have such large eyes in your head, remember that owls are not the same as humans. Their bodies have evolved to accommodate their eyes quite well, and they have several advantages in terms of eyesight due to their eyes’ tubular structure.
Owls have binocular vision, figuratively and literally. Besides the physical shape of their eyes, they can also see in 3D, similar to human beings and other birds of prey. This helps them to judge distance and depth very accurately; they can see most of their prey from over a mile away!
This is how owls’ vision works:
Seeing the highly developed physical structure of the owls’ eyes, it shouldn’t be surprising that they also have stellar eyesight. One of the fascinating features of owls’ eyes is that they have the ability to control the contraction and dilation of each of their pupils. This means that they can decide how much light they want to let inside each eye.
Owls are nocturnal and far-sighted, which makes some people wrongly assume that they can’t see during the day. The truth is that since these birds can control how much light their eyes process, many of the owl species have even better daytime vision than human beings!
What about the eyelids? How many of those do owls possess?
On a scale of 1-10, how unbelievable do we sound when we say that owls have three pairs of eyelids, and each performs their specific feature?
Yes, it’s true. They have an upper eyelid on each eye, which closes each time the owl blinks. The lower eyelids are closed when the owl is sleeping. Their last pair of eyelids is called nictitating membranes, which protect and clean their eyes.
Why do owls turn their necks so much?
Now, the question you’ve all been waiting for: why do owls turn their neck so much?
Well, you know that owls have eye tubes instead of eyeballs. But did you know that the said tubes are so large that their eyes can’t move at all?
Owls cannot roll their eyes or look to their side, up or down, while facing forward. Their eyes are fitted onto their faces and cannot be moved. They make up for this liability by being able to turn their heads to around 270 degrees! However, unlike common belief, owls cannot turn their heads all the way around.
An important skeletal modification in their bodies is the presence of 14 vertebrae, almost twice as many as humans. They also only have one bone fitted at the top of their backbone, while humans have two such bones. Both of these features allow their unusually flexible neck movements.
In the end
With this, we’ve reached the end of today’s article. Let’s quickly revisit everything we learned above before bidding goodbye.
We began by talking about whether or not owls have eyeballs, only to figure out that they don’t and are instead equipped with elongated, binocular structures called eye tubes. We also learned about how owls’ vision work and the reason behind them possessing three eyelids.
Would you prefer to have the ability to turn your necks as much as owls, or would you rather keep your movable eyes? Tell us in the comments below!