Did you know zebra print serves a greater purpose than making a bold fashion statement? Research has shown that the thin black and white stripes on a zebra’s hair coat actually deter flies from landing and feasting on them as they graze, exposed on the grasslands.
The equine industry has picked up on this fact in recent years, coming out with stylish and functional zebra print flysheets. More than a few people have surely been fooled from a distance, having to do a double take when they pass a field of horses and wait…was that a zebra I just saw?!
The Science of Stripes
According to a recent study by Hungarian and Swedish researchers, horseflies find zebra stripes incredibly unappealing, and the thinner and more numerous the stripes, the more the flies are deterred from landing on the animal.
Gabor Horvath, Ph.D., a researcher at the Environmental Optics Laboratory in the Department of Biological Physics at Eotvos University in Budapest, who also conducted a study on zebra coat patterns and horseflies, said, “We conclude that zebras have evolved a coat pattern in which the stripes are narrow enough to ensure a minimum attractiveness to [horseflies].”
He added, “It’s all about polarization. Polarization describes the way the electric vectors in light waves move in certain distinct patterns. Horseflies are very attracted to certain kinds of polarization. The horizontal polarization of water-reflected light, for example, leads them to water sources where they can mate, reproduce, and rehydrate. Linear polarization leads blood-sucking female horseflies to food sources such as horses.
“Dark colors on large animals reflect strong linear polarization, which attracts female horseflies to come to the dinner table. Light colors, on the other hand, produce weak polarization. When dark and light colors are striped together in zebra format, the polarization signals blend and confuse [their] eyes, and they tend to turn and fly the other way. The darkness of a horse’s coat is a disadvantage for horsefly protection, which is recognized only after our experiments.”
In his team’s experiments, they placed many platters full of vegetable oil in a fly-infested pasture. Each platter was painted in different patterns of black and white stripes or painted all black or all white. Black platters caught the most flies in the oil, and platters with the thinnest black and white stripes caught the fewest. According to Horvath, “This pattern resembles that found on the legs and faces of zebras.” The researchers ran a similar test on three-dimensional plastic horse models placed in the field, painted black, brown, white and zebra-striped and covered in sticky glue. Over the course of 59 days, the black horse caught 562 horseflies; the brown horse caught 334; the white horse caught 22 horseflies; and the zebra model caught only eight.
Zebra Print is All the Rage This Season
If horse owners aren’t interested in painting their equine friends, they may want to consider dressing them up as zebras – even if fly season doesn’t coincide with Halloween. “Horse keepers could protect their black and brown horses … with the use of white or even zebra-striped coverings,” Horvath said. “A zebra-striped horse rug would be ideal.”
New, patented, commercial horsefly traps that attract horseflies with high levels of linear polarization are also currently under development and testing in Hungary, based on this research, Horvath noted.
Jennifer Kindred-Bulbulia, founder of The BK Foundation Therapy and Wellness Center and the former owner of Corona Animal Hospital, which was located in California, offered some advice for those who might want to paint stripes on their horses. “When painting the horse, it’s important to use organic plant based natural items.” She stressed that it’s imperative not to use regular paint, which can cause toxicity and other issues such as skin problems. Plant based solution will wash away with sweat and water so working horses will have to be painted everyday.
