Have you ever wondered how cats see the world? Can cats really see in the dark? What colors do cats see, and can they see those colors when it’s dark?
Cats Have Excellent Night Vision
Cats have evolved to be proficient hunters. Part of this evolution has been the development of the ability to see in low light conditions like dawn and dusk, times of the day when their prey is most active.
Hunting in low-light conditions also has the advantage of helping them to avoid larger predators that are typically active during daylight hours.
However, cat’s cannot actually see when it’s completely dark. This is because the light-receptive cells in a cat’s eyes need at least some amount of light before they can be stimulated and send vision signals to the brain.
Cats See Things Differently Than Humans
Rods and cones are the two main types of photoreceptor cells found in the retinas of most mammals, including cats and humans. Each type of cell has a specific role in vision, and the differences in the proportion and types of rods and cones between species results in differences in how they see colors.
Rods are primarily responsible for vision in low-light conditions. They are extremely sensitive to light but do not detect color. Cone cells, on the other hand, are responsible for color vision and work best in bright light conditions.
Cats have a higher proportion of rod cells compared to cone cells, which means they have better night vision than humans. However, like humans, the cone cells are not activated in dim light, meaning that neither humans nor cats perceive color when light is dim and instead see shades of gray (1).
But what about cone cells? How do cats differ from humans in color perception?
What Colors Do Cats See?
Humans have three types of cone cells (red, blue, and green), allowing us to see light in a broad spectrum in the range of 380 to 700 nm (2). Cats, on the other hand, have long been thought to have two types of cone cells in their retinas, allowing them to only see colors in the blue and green spectrums.
However, research has found that cat’s color perception has three peaks, at 450, 500 and 550 nm which corresponds to blue, cyan, and green color wavelengths, suggesting that they have a third type of cone although it is not the same one that detects red colors like humans have (3,4).
How Colors Appear to Cats
Even with three different types of cone cells, cats can generally only see color in the green and blue spectrums (and shades in between).
They do not have the necessary cone cells to see red, orange, or yellow hues, and colors in this spectrum. Reds and pinks will appear more green, while purple can look like another shade of blue. Some colors in the red spectrum may be seen as shades of gray.
The reduced ability to see colors in the red spectrum is believed to be somewhat comparable to color blindness in humans. However, turning this knowledge into a clear understanding of the colors a cat actually sees is quite complex.
The primary reason for this uncertainty is that visual perception involves not just the physical structures in the eye but also how the brain interprets the signals it receives. We can’t directly know how cats see colors because we can’t experience or measure their perceptions.
Still, by looking at the structure of their eyes and comparing it to other animals, including humans, we can make educated guesses about what they are seeing and how they probably perceive color.
Other Ways Cat Vision Differs From Humans
Visual Acuity
Cats and humans differ significantly in their visual acuity. While cats possess excellent night vision due to a high density of rod cells in their retinas, their overall visual acuity is not as sharp as that of humans. This means that cats do not see fine details as clearly as humans do.
Despite this limitation, cats compensate by having an exceptional ability to detect quick movements, which is particularly useful in the dim lighting conditions in which they evolved to hunt.
Tapetum Lucidum: A Boon for Night Vision
A distinctive feature of cat eyes is the tapetum lucidum, a reflective layer behind the retina that increases their ability to see in the dark. Humans do not have a tapetum lucidum
This structure acts like a mirror, reflecting light that passes through the retina back into their eyes, increasing the light available to the photoreceptors. This is why cats’ eyes often appear to glow when light shines on them at night.
The Role of Large Cornea and Vertical Pupils
Cats have a large cornea and vertical pupils that expand significantly in low light. These features allow more light to enter the eye and improve their vision under various lighting conditions.
The vertical pupils can close to a small slit during bright light, protecting the sensitive retina from excess light and increasing the focus.
Do Cats Have Color Preferences?
While it’s hard to determine if cats have preferences for certain colors, their attraction to certain toys and objects can sometimes give clues. Cats might be more drawn to items in shades of blue and green, which they can see more clearly.
However, much of a cat’s interaction with objects is influenced by texture and movement rather than color. Ultimately, their color perception is only a small part of how they experience the world around them.
Summing Up
Cats’ vision has evolved to be specifically tailored to their ecological roles as nocturnal hunters. While they are well-equipped for low-light environments, this comes at the cost of color and detail perception.
Understanding how cats perceive the world can help cat owners and professionals create better environments for these fascinating creatures. While cats may not see the rich palette of colors humans do, their unique vision adapts them perfectly to their nocturnal lifestyles, making them the agile and perceptive animals we love.
[Image credits: All images are used under license or with permission]
Here’s a related article you might be interested in: Why Are My Cat’s Eyes Red?
Sources
- Seeing lightness in the dark
- Visible Light
- Vision in the Animal Kingdom
- Neutral point testing of color vision in the domestic cat
- Trichromatic Vision in the Cat
- Eye Structure and Function in Cats
