The Research
Our zebra stripe is not a graphic choice. It comes out of a body of peer-reviewed work, published between 2012 and 2020, on why zebras are striped and how biting flies respond to high-contrast patterns. Below are the papers themselves, what each one actually found, and — just as importantly — what none of them show.
The studies
1. Striped patterns are the least attractive to tabanid flies (2012)
Egri, Á., Blahó, M., Kriska, G., Farkas, R., Gyurkovszky, M., Åkesson, S., & Horváth, G. Polarotactic tabanids find striped patterns with brightness and/or polarization modulation least attractive: an advantage of zebra stripes. Journal of Experimental Biology, 215(5), 736–745.
doi.org/10.1242/jeb.065540
Sticky test boards and life-size horse models were set out in a Hungarian field. Striped surfaces attracted fewer tabanid horseflies than either plain dark or plain white ones, and the narrower the stripes, the fewer flies arrived. The widths that performed best sit close to the stripe widths on real zebra hide. The authors put the effect down to the way stripes break up polarized light, which is one of the cues tabanids use to find a host.
2. Of five competing explanations for zebra stripes, biting flies is the one that holds up (2014)
Caro, T., Izzo, A., Reiner, R. C. Jr., Walker, H., & Stankowich, T. The function of zebra stripes. Nature Communications, 5, 3535.
doi.org/10.1038/ncomms4535
A comparative study across equid species and subspecies, testing camouflage, predator defence, heat management, social signalling and biting-fly avoidance against the actual distribution of striping. Only biting-fly avoidance tracked the patterns consistently. Striping showed no reliable relationship with woodland cover, maximum temperature or predator presence.
3. Stripes painted on a human-shaped model cut horsefly landings roughly ten-fold (2019)
Horváth, G., Pereszlényi, Á., Åkesson, S., & Kriska, G. Striped bodypainting protects against horseflies. Royal Society Open Science, 6(1), 181325.
doi.org/10.1098/rsos.181325
Three life-size mannequins — one dark, one beige, one dark with white painted stripes — were coated in insect glue and left outdoors. The dark model caught roughly ten times as many horseflies as the striped one, and the beige model about twice as many. This is the closest the literature gets to a wearable pattern, though what was tested was painted skin, not fabric.
4. Flies circle zebras as often as horses, but land far less (2019)
Caro, T., Argueta, Y., Briolat, E. S., Bruggink, J., Kasprowsky, M., Lake, J., Mitchell, M. J., Richardson, S., & How, M. Benefits of zebra stripes: Behaviour of tabanid flies around zebras and horses. PLOS ONE, 14(2), e0210831.
doi.org/10.1371/journal.pone.0210831
Researchers filmed tabanids around captive zebras and domestic horses. Approach rates were similar; landing rates were not. Flies coming in on a zebra failed to decelerate and bumped off rather than settling, and those that did land stayed about a second, against ten seconds on a horse. The same horses were bothered far less in a striped rug than in a plain black or white one. Notably, their uncovered heads were bitten just as much in every condition — the effect only covers what the stripes cover.
5. Cattle painted with white stripes carried about half as many biting flies (2019)
Kojima, T., Oishi, K., Matsubara, Y., Uchiyama, Y., Fukushima, Y., Aoki, N., Sato, S., Masuda, T., Ueda, J., Hirooka, H., & Kino, K. Cows painted with zebra-like striping can avoid biting fly attack. PLOS ONE, 14(10), e0223447.
doi.org/10.1371/journal.pone.0223447
Japanese Black cows were painted with black-and-white stripes, with black stripes, or left alone. The white-striped cows carried roughly half as many biting flies as either control group, and performed about 20% fewer fly-repelling behaviours — tail flicks, skin twitches, head throws.
6. It may not be stripes specifically (2020)
How, M. J., Gonzales, D., Irwin, A., & Caro, T. Zebra stripes, tabanid biting flies and the aperture effect. Proceedings of the Royal Society B, 287(1933), 20201521.
doi.org/10.1098/rspb.2020.1521
This one tested whether a particular motion illusion, the aperture effect, explained the earlier results, by comparing striped rugs against checked ones. It did not: checked rugs deterred landings about as well as striped ones. The honest reading is that the deterrent effect appears to come from bold, high-contrast patterning in general rather than from stripes in particular.
What this research does not show
We would rather tell you this ourselves than have you find it out later.
- It is about biting flies. Every study above concerns tabanids — horseflies and deer flies — or biting flies on cattle. None of them tested mosquitoes, and none tested ticks. We do not claim any effect on either.
- Nobody has tested clothing. The work used sticky boards, mannequins, horse rugs, live zebras and painted cattle. No published study has measured a commercially produced striped garment on a person, including ours.
- Stripes may not be special. The 2020 study found checked patterns performed about as well, which suggests contrast matters more than the specific stripe shape.
- Coverage is the limit. In the 2019 horse-rug work, the animals' uncovered heads were bitten at the same rate regardless of what they wore. Whatever the pattern does, it does it where the pattern is.
- This is clothing. BRC garments are apparel. They are not a repellent, an insecticide, or a medical or protective device, they are not registered as any of those things, and we make no claim that they prevent bites or disease. Where there is real disease risk, use a registered repellent and take advice from a health professional.
Why we made it anyway
Because a high-contrast pattern printed into a hoodie costs you nothing to wear. There is no spray, nothing to reapply, nothing absorbed through your skin, and nothing that wears off after four hours. The research above is why we chose this pattern rather than any other one, and it is the whole of the case we are making for it.