According to new research, hummingbirds are able to see colours which we humans cannot even imagine, thanks to the cone in their eyes we don’t possess.
The findings from the experiments with wild broad-tail hummingbirds in Colorado point out that the capacity to spot non-spectral colours may play a major role in the attitudes like mating, feeding, and escaping from predators.
Unlike us, who have 3 types of color-sensitive cone cells in the eyes, birds have 4 that help them process the color differences.
Colors We Are Able to See vs. Colors Birds Can See
With 3 cones, the human eye is able to perceive the trichromatic colors made from a blend of red, green, and blue light.
This process enables our brains to see the non-spectral color of purple as it’s a combo of blue and red.
On the other hand, the animals like birds with one cone plus are able to perceive an even larger color spectrum as they’re sensitive to more types of light wavelengths.
So, they can spot colors we can’t even imagine. According to evolutionary biologist Mary Stoddard from Princeton, humans are color-blind in comparison to birds and numerous other animals.
She explains that the extra cone doesn’t just extend the range of visible colors, but it also potentially enables them to see color combos such as ultraviolet and red and ultraviolet and green.
Caswell Set Out to Test This Claim with Her Team
For the purposes of the test, they set up bird vision LED tubes that display various colors, including the non-spectral ones we can’t see.
They placed the specialized devices near water feeders, some with sugar water next to one color and others with plain water near a different color.
They then swapped the positions of the feeders to see if the birds were able to use the color indicator to find out which feeder is which.
The experiment lasted for a total of three years and thousands of feeding sessions. At the end, the scientists discovered that the birds found it easy to distinguish between the various non-spectral colors and get to their sweet reward.
Despite the impressive results, researchers explain that a lot is still unknown.