Whether you’re wondering if horses see in color or questioning how else their visual range compares to yours, knowing more about equine optics will satisfy your curiosity.
Understanding how your steed sees will help you catch potential eye conditions. The perception of color, light, and depth also influences their behavior. Gaining insight into these details can lead to better training, reduce common problems, and help you gain their trust.
How do Horses See the World?
Let’s start with the basics of how sight works for many creatures. At the back of the eye is a thin tissue layer called the retina. If your eyes were a traditional camera, the film would be your retina.
This innermost layer contains photoreceptor cells that turn light rays into electrical signals processed by the brain’s optical center. Those important cells are known as rods and cones.
Rod cells are more sensitive to movement compared to cones. They are responsible for seeing in low light but are not able to perceive color. Cones are in charge of color vision and the ability to focus on the shapes of objects clearly. They are more active at higher levels of light. Animals that need to detect movement and objects in the dark have more rods compared to humans.
Like humans, animals may be able to see color depending on the type of cones in their eyes. The majority of humans have three types of cones. These red, blue, and green cones detect a wide color range. The overlapping of cones allows our brains to perceive millions of shades. Human colorblindness can develop when a cone is missing or not properly in control of its hue.
What Colors Do Horses See?
The varied spectrum of animal color vision depends on the type of cones present in each species. With cones present, we now know that an animal can observe colors, but we cannot tell how the animal notes the gradation or strength of each color.
Many people have strong and diverse opinions on their perception of color. It’s possible that horses and other animals have varying views as well.
The three cones that allow most of us to admire the color wheel’s full scope are responsible for trichromatic vision. Broncos have dichromatic vision, meaning there are two types of cones. They can only see two hues, which many believe to be blue and yellow.
Rather than seeing color blends, horses likely see objects of other colors as desaturated versions of blue and yellow or as white or grey.
Mustangs can sometimes react unexpectedly because of these differences. Some compare their sight to the red-green colorblindness of people. Because horses cannot easily tell the difference between yellow and green, they may not notice a yellow block on green grass as clearly as you do. If you need a mare or a stallion to avoid a jump rail or other obstacle, use colors that contrast with the scenery around them.
Now let’s focus on acuity. Nearsighted means not seeing objects far away very well. Farsightedness is the opposite condition where close-up items are difficult to observe clearly. Horses can have either issue, and their eyesight deteriorates as they age.
Static items and details are also difficult for them to examine. If you wear strong corrective lenses, view the landscape without them to get a better idea of your animal’s perspective.
Your doctor can determine your visual field by having you cover one eye and stare straight ahead. They move one finger to the sides, above and below, to help them determine how well you can see peripherally. Horses cannot see directly ahead or behind them, but their eyes immediately notice peripheral movements. These blind spots exist because their eyes are positioned on the sides of the head.
While clarity is an issue, equine eyes magnify objects by 50%. Having the largest eyeball of any mammal on land has its benefits! Because they only look with one eye at a time, horses have what is known as monocular vision. To view something in a more binocular or human way, shifting head positions makes it possible for them to study the same object with the other eye.
You know that the barn cat has better night vision than you, but horses can see even better! Horses have more rod cells in their eyes, so they are more sensitive to light. They need about 15 minutes to adjust to new lighting, which explains why twilight can be difficult for them. Like cats, the “tapetum lucidum” behind their retinas provides extra light reflection to help them see.
Caring for Your Horse’s Eyes
Reviewing common eye conditions and disorders will shed some light on why you should check on your horse a couple of times each day. Finding an experienced veterinarian is one of the best ways to care for your companion’s eyes and overall wellbeing.
However, for everyday tending, there are steps you can take to prevent accidental injuries or infections to the eye. Be attentive and catch problems early.
Be on the lookout for injury or infection as there are many ways to detect whether your horse’s vision is fine. Is there a noticeable increase in head movements from side to side or melodramatic jumpiness and spooking? Is your animal rubbing or squinting an eye? Is there a noticeable sensitivity to light, or are the eyes watery or inflamed? Cloudy or red eyes are also a cause for concern.
Infections can occur when a foreign object has scratched or gets stuck in the eye area. Conjunctivitis, bacterial and parasitic infections are also possible. Do your best to notice any unusual signs.
Your veterinarian can attend to any damage after a careful exam. Keeping your horse’s home clear of sharp edges and as dust-free as possible is an excellent first step to protecting your animal’s ocular area.
Equine eyes already have excellent congenital protection. Eyelashes act as sensory hairs to induce an automatic blink reflex when something is too close or threatening.
Another natural defense mechanism is the third eyelid, or nictitating membrane, which seals the eyeball to protect it from scratches and provides moisture to the eyes. Along the iris edge is the corpora nigra, which acts like built-in sunglasses, partially blocking excess light.
A Beautiful World
Do horses see in color? What colors do horses see? While there’s still extensive debate regarding which specific colors they can perceive, we know they’re able to identify some hues.
Horse handlers can further connect with these majestic animals by studying their eyes and other senses. It’s not yet possible to fully understand how their brain perceives things optically, but now you have some pieces to the ocular puzzle.
The enigmatic mustang will continue to enchant those who spend time near them. Your horse has essentially the same eye structure as you, but with many unique characteristics. Recognizing similarities and differences will help you appreciate that you each evolved vision specializations that better fit your needs. The next time you gaze into their big, beautiful eyes, you’ll see a bit more from their point of view.