Evrim Yazgin
Cosmos science journalist
Ever wondered what the world looks like to an animal? A new camera has been developed which can replicate in real time the colours seen by different animals.
Animals see varying ranges of colour.
It’s all about the colour-sensing cone cells in an animal’s retina. Humans have 3 cones for perceiving wavelengths of light that are red, green and blue. Combinations of these wavelengths produce the plethora of beautiful hues that we can enjoy.
Of course, not all humans have fully functioning cones, leading to colour blindness or colour vision deficiency.
Some animals see less colour than humans.
Dogs, for example, are much better at seeing blues and yellows, than purples, greens, reds and oranges. Cats have two colour-detecting cones for seeing blue-violet and yellow-green wavelengths of light, but not red-orange.
Some animals can see beyond the “visible spectrum” of human colour range.
Hummingbirds and bees, for example, can see into the ultraviolet part of the spectrum which helps them find nectar. Because we can’t see UV light, we literally can’t even imagine the colours that these animals can see.
We can tell all of this by examining the cones in an animal’s retina. But it’s another thing again to actually see the world as they do.
A new camera aims to do just that.
Traditional methods of producing “false colour” images to show the world as animals do are often time consuming. The novel camera can capture animal-eye-view videos of moving objects under natural lighting.
It is detailed in a paper published in the journal PLOS Biology.
“We’ve long been fascinated by how animals see the world,” says senior author Daniel Hanley, an assistant professor of biology at the George Mason university, US. “Modern techniques in sensory ecology allow us to infer how static scenes might appear to an animal; however, animals often make crucial decisions on moving targets (e.g., detecting food items, evaluating a potential mate’s display, etc.).”
The camera records video in 4 different colour channels: blue, green, red and UV. The data is processed then processed again based on existing knowledge of the photoreceptors in the animal’s eyes, creating an accurate representation of the animal’s vision.
Comparing with traditional spectrophotometric methods, the team found the real-time images they caught were accurate to 92%.
“The camera system and the associated software package will allow ecologists to investigate how animals use colours in dynamic behavioural displays, the ways natural illumination alters perceived colours, and other questions that remained unaddressed until now due to a lack of suitable tools,” the authors write.
“Finally, it provides scientists and filmmakers with a new, empirically grounded approach for depicting the perceptual worlds of nonhuman animals.”
