had a student ask me a couple of weeks ago if horses see in color. I thought about
it and said, Well, as I understand it I dont think they see all the
colors we do, I think they see in shades of color
kinda like cats.
It was a reasonably lucky assumption on my part, but I wanted to know the specifics
of if horses can see in color and what colors they do see.
is a given that horses have a different field of vision than we do simply cause
their eyes are built and located differently than ours. Because horses eyes are
on the sides of their head (as opposed to the front like cats or like ours) the
horse views a much larger field of vision.
book The Body Language of Horses, published in 1980, Tom Ainslie and Bonnie
Ledbetter state, Many authorities have proposed that horses are nearsighted
as well as color blind. Experimental findings support both contentions, but not
As time progress our understanding
and research progressed. As discussed in Desmond Morriss book Horsewatching:
Why does a horse whinny and everything else you ever wanted to know, published
in 1988, he sates that For many years horses were said to be color blind
but we now know that this is not the case, although color vision is much weaker
in them than it is in us. They are most responsive to yellows, then greens, then
blues, and least of all reds, according to recent experiments. (2)
Micklem, in his book Complete Horse Riding Manual published in 2003
he says that Research has shown that horses are dichromates, which
means that they have limited color vision. They can distinguish between light
and dark, between reds and blues, but not between greens and grays. This is why
you will not find green or gray poles used in a grass showjumping arena.
Hill, in her book How
to Think Like a Horse: The Essential Handbook for Understand Why Horses Do What
They Do published in 2006, she supports Micklems assertion that
horses are dichromates. The horses eye has two types of cone cells
in the retina that are sensitive to color whereas a human has three types of cone
cells. Whether horses can see colors as we do is still widely debated. Most researches
agree that horses do have more than shades of gray discrimination
but not the color range of humans. Exactly which colors horses see is sill unresolved.
Equine vision expert Dr. Brian Timney, of
the University of Western Ontario, explains that horses are like humans with color
deficiencies. For example, humans with red-green color vision defects have only
two hues (blue and yellow) rather than four. Such dichromates do not see intermediate
hues, seeing instead white or gray or a faded form of the two colors. (5)
have little difficulty in discriminating red or blue from gray. With respect to
green and yellow, the results are mixed, says Timney. His findings are similar
to those from earlier studies but other researchers results differ. Exact
answers have proven elusive in color vision research because of the difficulty
in designing experiments with adequate controls (such as for brightness).
In the end, there is still debate about what colors
horses see. It would be fair to say that there is a general agreement that horses
can see colors, yet what colors those are remains to be conclusively confirmed.
(1) Ainslie, Tom & Bonnie Ledbetter. The Body Language of Horses:
Revealing the Nature of Equine Needs, Wishes and Emotions and How Horses Communicate
Them - For Owners, Breeders, Trainers, ... Other Horse Lovers Including Handicappers.
William Morrow and Company, New York. 1980. Page 30.
(2) Morris, Desmond. Horsewatching:
Why does a horse whinny and everything else you ever wanted to know. Crown Publishers,
Inc., New York. 1988. Page 41.
(3) Micklem, William. Complete Horse Riding
Manual. Dorling Kindersley Limited, New York. 2003. Page 46.
(4) Hill, Cherry.
How to Think Like a Horse: The Essential Handbook for Understanding Why Horses
Do What They Do. Storey Publishing, North Adams, MA. 2006. Page 24.
M.S., Ph.D, Evelyn B. How Horses See. http://www.completerider.com/horsemanfeb2003.html.