The Vision of Cats vs. Dogs
Comparing the Eyesight of Humans, Cats, and Dogs
The human eye is incredibly complex. It can receive vast amounts of visual information and has the ability to differentiate between millions of colors. On a clear and starry night, the human eye can see nearly 50 miles away. Of course, we aren’t the only species with impressive visual acuity but how does the performance of our eyes stack up to that of our feline and canine friends?
Cats have a wider field of vision than humans (about 200 degrees compared to 180 degrees of vision for humans). This greater peripheral vision aids cats in spotting the movement of prey while hunting. Since they are crepuscular (active during both dusk and dawn), their vision is adapted to aid in this behavior. This is also the reason for their excellent low-light vision. Cats also have better near-vision than dogs but still less than humans.
The large and elliptical shape of their corneas helps them in gathering light. The extra rods in their eyes also make it possible for them to sense any motion from prey in their peripheral vision, as well as enhancing night vision. In addition, cats have a special feature behind their retinas, called a tapetum, which is thought to further improve night vision. The tapetum acts like a mirror, reflecting the light that passes in the eye back again, allowing it to be picked up a second time. This is the reason cats’ eyes glow in the dark. Due to all of these special adaptations, cats’ eyes are thought to be about twice as efficient as dogs when it comes to seeing in low light situations.
However, when it comes to color vision, felines don’t have an edge. They can see shades of green and blue, but there are some colors that are confusing to them, like pink and red. They seem to have more limited color vision than dogs. However, like dogs, cats rely more on detecting motion than seeing fine details, so this loss of color doesn’t affect them greatly. They are also rather nearsighted, and cannot see objects that are a great distance away, as they have evolved to “pounce” on targets from relatively short distances. They rely on their other senses (such as hearing and sense of smell) to help identify potential targets from afar.
It’s true dogs don’t see things exactly the way that we do. However, there are some common misconceptions about how our canine friends view the world around us. They don’t just see the world in black and white, as portrayed in many TV shows and movies. In fact, when compared to people, dogs’ color vision is actually quite similar to a “red-green” colorblind person. However, there are great differences between other aspects of dogs’ vision and that of our own.
Both dogs and humans (like cats) have two types of receptors, cones, and rods. Dogs only have two types of cones, which makes their color recognition and vision very limited. Like cats, dogs also rely more on motion detection than fine detail and have adapted their vision to detect prey from a distance. Dogs can see hand signals from a mile away, which is greater than cats. This means that, although they most likely can recognize more colors than cats, this also isn’t of a great benefit to them. They do, however, have difficulty focusing clearly on objects closer than a foot. They also have a greater field of vision than both cats and humans. They can see at 240 degrees, compared to 200 degrees for cats and 180 degrees for humans.
When it comes to the sense of smell, however, humans aren’t a match for dogs. Having more rods than humans, another advantage is having a better night vision. Dogs also have bigger pupils which allow more light to enter into their eyes. And, like cats, they also have a tapetum which helps them absorb more light.
The Edge of Humans’ Vision
The human eye is an important organ of the human body, allowing us to interpret the things we see as objects, shapes, and colors. Our vision allows us to see in both dim light and bright light and is used in almost all the activities that we do. It is an essential tool for learning things around us, such as language, computers, health and active developmental activities.
If you look at the anatomy of the human eyes and that of the cats and dogs, you will find a different structure. Today, along with paying attention to the health of our bodies, we also need to give our eyes extra care to maintain good health. As we age, vision can start to fade. It is therefore recommended to eat healthy foods that are rich in vitamins C, E, zinc, and lutein, as the eyes require proper nutrition just like any other part of the body. Exercise is also one of the keys to improving the health of the eyes and to prevent the possible risk of eye impairments like cataracts. We also recommend annual eye exams from your ophthalmologist, as with many medical problems, prevention of a disease is often more effective than curing it.