Above all, butterflies are known for their beautiful wings. But for years, most people have believed that butterflies are incapable of actually seeing them.
What are the facts behind the belief that butterflies can’t see their own wings?
Butterflies can see their own wings, thanks to their nearly 360-degree field of vision. They can also see ultraviolet markings on other butterflies’ wings, which helps them to identify various types of butterflies and potential mates. Each of a butterfly’s eyes has up to 17,000 light receptors that create a mosaic image of the scene surrounding it.
Continue reading to learn about where the myth of butterflies not being able to see their wings originated.
You’ll also discover several components of butterflies’ vision, such as their compound eyes and impressive ability to see colors.
The Myth That Butterflies Can’t See Their Wings
For several years, there’s been a widespread myth that butterflies cannot see their own wings.
It’s thought that this idea gained traction due to the late Glee actress Naya Rivera’s 2016 book, Sorry Not Sorry: Dreams, Mistakes, and Growing Up.
In this book, she says, “Butterflies can’t see their wings. They can’t see how truly beautiful they are, but everyone else can. People are like that as well.”
While the quote is a lovely sentiment that quickly gained traction on social media, it’s simply not true. Butterflies can absolutely see their own wings; they have nearly 360-degree vision.
Butterfly Vision Characteristics
Butterflies have some amazing visual capabilities, such as a wide visual field and impressive color vision.
Although they’re nearsighted, they have other visual strengths.
Compound Eyes
The eyes of butterflies are spherical compound eyes. Each of a butterfly’s two eyes has as many as 17,000 individual light receptors with microscopic lenses called ommatidia. The ommatidia work together to create a mosaic view of a butterfly’s environment.
(Nearly) 360-Degree Visual Field
Butterflies are believed to have the widest visual field of any wildlife creature.
Most butterfly species have a visual field of around 344 degrees. This means they almost have a 360-degree visual field on the horizontal plane!
As far as the vertical plane, butterflies can see nearly 360 degrees as well.
For comparison, humans typically have a visual field of just 190 degrees.
Butterflies’ wide fields of vision enable them to protect themselves from predators, especially birds.
Monocular Vision
As humans, we have binocular vision, which means that the information we take in from each eye is combined into a single visual image. Our binocular vision gives us the ability to assess distance and depth.
Butterflies, however, have monocular vision. While a butterfly still has two eyes, those two eyes are located on opposite sides of its head.
Each of its eyes can view different images at the same time, rather than seeing a single combined image.
One downside of monocular vision is that butterflies do not have the same type of depth and distance perception that creatures with binocular vision have.
Impressive Color Vision
Butterflies can see colors that are not visible to the human eye. While they cannot pick up on detailed patterns, butterflies’ ability to view a vast array of colors is nearly unmatched.
The common bluebottle butterfly, for instance, has at least 15 types of photoreceptors in each eye. Most butterflies have six or more.
Other insects, meanwhile, usually only have three types of photoreceptors per eye.
Photoreceptors are similar to the rods and cones found in human eyes, and we only have three types of cones: blue, green, and red.
Even so, we can still see millions of different colors. Just imagine how many colors butterflies can see with as many as 15 photoreceptors!
Find Mates
One way that butterflies use their incredible color vision is to help them find mates.
Female orange sulfur butterflies can determine the age and reproductive fitness of competing males by assessing the ultraviolet scales on their wings. They can see these scales with special receptors in their eyes.
If a male has scales missing, he’s likely older and less likely to be a viable mate.
Identify Nectar-Producing Flowers
Another way butterflies use their color vision is to identify flowers that produce nectar. Nectar availability is displayed through “pollen guides” or “honey guides” that feature visual contrast in their coloring or form.
While humans can sometimes see this type of visual contrast, many flowers’ pollen guides are in the ultraviolet range.
For instance, the black-eyed Susan has plain yellow petals when looked at with human eyes. But butterflies and other insects see a dark center in these petals, resulting in a bullseye effect in the ultraviolet range.
Another example of this is the horse chestnut tree. When nectar is being produced, the petals on the tree are yellow. When it’s no longer being produced, the petals turn red.
Distinguish Other Types Of Butterflies
Yet another use for butterflies’ color vision is to identify various types of butterflies.
While many of these beautiful insects look the same to human eyes, they have ultraviolet markings that make it easy for other butterflies to distinguish them.
Conclusion
Although many people believe that butterflies can’t see their own wings, this isn’t true.
Butterflies are absolutely capable of seeing their wings because they have an impressive field of vision that spans 344 degrees–just short of a full 360 degrees.
This vision field is extremely helpful in enabling butterflies to protect themselves from predators like birds.
Not only can butterflies see their own wings, but they can see ultraviolet markings on other butterflies’ wings that are invisible to the human eye. These ultraviolet markings help butterflies determine whether others would make good mates.
They also make it easy for these insects to identify different types of butterflies. Flowers often feature ultraviolet indicators when they are currently producing nectar as well.
Butterflies have compound eyes that are made up of as many as 17,000 individual light receptors called ommatidia. All of these light receptors come together to create a mosaic-like image of a butterfly’s current surroundings.