Have you ever wondered; can bees see red? You might never have thought about a question like this unless you've raised bees yourself and got the idea to paint their hives in different colors like I did. Last summer, I painted my Langstroth hives different colors just for a little variety. I used the colors of wildflowers in my area; blue, yellow, violet, and white.
Can Bees See Red?
- I'd heard somewhere that bees can't see the color red, so I avoided using it. But it got me wondering whether or not what I'd heard was true. After doing a little research, I was fascinated by what I discovered. However you've come to have this question yourself, the answer may surprise you.
- Some animals see fewer colors than we can, and some, like birds, can see more colors than human beings. The way animals see varies widely depending on how they are adapted.
- Whether you're a bee, a human, or any other creature, you can see objects around you because of the light reflected off of those objects. The reflected light enters the eye, the photoreceptors in the eye absorb that light and then it's interpreted as color by the brain.
- Human beings can see light in a range of different colors. But we have only three photoreceptors in our eye. These receptors can perceive red, blue, and green. The reason that you and I can see more than just these colors is that other colors are created by combinations of the three primary colors in our brains.
- Bees have the same number of photoreceptors, but they see in different colors. Their trichromatic eyes allow them to see blue and green, just like us, but instead of red, they can see in ultraviolet.
- So how do we know this? Because bees play such a vital role in growing the food we eat, our little black and yellow friends have been observed by beekeepers for centuries. But it was Karl Von Frisch who applied scientific methods to his experimentation with bees that unveiled hidden knowledge about how bees see.
'Beecause' of Science
- It's thanks to the valiant efforts of Von Frisch, studying honeybees and their behavior, that humans have come to confirm that bees use their capacity to see color to help them find flowers to pollinate.
- In 1915, Frisch conducted experiments using cards of different colors. He placed bee food on a card then removed the food in later trials to see if the bees would return to the same-colored card where the food had been.
- Answering the question, "can bees see red?" he found the bees returned to the cards in all the colors he tested except for one: red. Frisch concluded that this color was outside of the bees' ability to perceive.
- So, when answering the question, "can bees see red," a red object won't appear invisible; they'll still see something is there. However, to a bee, red is indistinguishable from black. This conclusion was made from the results of a study decades later by Professor Kahn on the wavelengths of light visible to bees. The results of this study lead us to understand that while red and infrared were imperceptible, bees can see in the ultraviolet spectrum, unlike humans.
The Advantages Of Ultraviolet
- So why can bees see in ultraviolet but humans can't? One clue has to do with the way that this adaptation is useful to bees' survival. To state the obvious flowers are colorful. But to a bee, there's even more to see.
- In addition to seeing subtle differences in the shade of flower petals, which look different depending on their nectar content, bees can read the places on a flower where the most nectar can be harvested. This is why it's a useful survival skill for a bee to distinguish between leaves, which hold no nectar, and flowers which do.
- Not only is seeing in color useful to bees but being able to see in ultraviolet is especially useful because there are actually ultraviolet patterns on the flower. They're invisible to us, but to bees, they're like runway lights that guide them to the sweet nectar inside flower bulbs.
- To a human, a white flower is a white flower. But consider how different those white flowers look from one bee to another to, which can see that each has a unique UV signature. These are unique enough that a bee can pick out one specific flower in an entire field even if they're of the same variety.
- UV isn't just crucial for use in finding flowers; it can play a role in how bees behave too. In experiments which isolated bees from sources of UV light, scientists discovered that their subjects lost interest in leaving the hive in search of nectar even after they began to starve.
The Eyes Have It
- Because their unique eyes are such a useful adaptation, bees can pick up these signals much more quickly than we humans can. Imagine you're looking at a field of gorgeous wildflowers on a spring day. You probably wouldn't be able to distinguish between the individual flowers because there are too many of them. But for a bee, it's no issue.
- Bees can pick out a color faster than any other creature that we know of. They can distinguish between flowers while flying even if they only see a brief flicker of movement. If you've ever tried to swat at a bee only to have it easily evade you, you've seen this quick perception of movement in action. Their compound eyes help them see 280 degrees at once.
- In addition to their two large compound eyes, bees also have three smaller eyes at the top of their heads called occeli. It's the occeli that help the bees see in ultraviolet, in addition to helping them keep an up-down orientation while flying. Since there's more light coming from above than below, it helps them distinguish the sky from the ground.
- Even when there's no sun to see by, bees can still use their incredible compound eyes to help them find their way home again. Sunlight is diffused, but polarized light, which isn't perceivable by humans, is super-focused. These invisible beams in the sky help bees to reorient and return home wherever they are.
Why Bees Matter
- So we've answered the question, "can bees see red,", but does this matter? While it might seem like a trivial detail to know that a bee can't see red, understanding how bees see is incredibly important.
- Some animals rely on senses other than sight, so they don't need sophisticated eyes, but bees rely on sight to navigate. This means that they need to be able to see in order to pollinate. This matters immensely not just for those of us interested in raising bees and cultivating honey. So many of the crops we take for granted would simply be impossible to grow without bees.
- Have you had an apple today? How about some sliced cucumber on your salad? I like to keep a bag of almonds nearby for munching on throughout the day. These and many other agricultural products, including avocados, onions, grapefruit, etc. would be impossible without bees.
- A study of bees and their cumulative impact on the economy estimated that bees contribute nearly $15 billion annually to the U.S. economy because of all the produce which is dependent upon them. This makes the decline of bee populations potentially devastating not only to farmers but also consumers who rely on these foods every day.
How To See Like A Bee
- Early attempts to capture how bees see the world using technology used a single camera to approximate the bee's field of vision. But this one-camera model was thrown out in favor of one that more closely resembled a bee's compound vision by using thousands of tiny lenses and mirrors. Cameras like these give us a general idea of the colors bees can perceive and what the world looks like to them.
- Technology that can be used to see how the way bees do has wide-reaching potential. Far more than just a novelty, this information could be used to create a failsafe if the number of honey bees drops precipitously. Without bees, we may be stuck using technology to try to replace the role they play in food production.
- That's no easy task when you consider just how sophisticated bees are at pollinating. Thanks to adaptations over millions of years, bees are incredibly adept at finding flowers to pollinate, and they can do so even in very windy conditions. Can you imagine a fleet of human-designed drone robots simultaneously doing all the same tasks that bees do as efficiently?
- Of course, even without honey bees, there are still natural pollinators that we can rely on. Hummingbirds are the most adroit pollen collectors among all species of birds. And just like other birds they can see in a range of colors, including red. For this reason, they often have red flowers all to themselves since these are less often disturbed by bees looking for nectar.