Study
The function of zebra stripes
Caro, Tim; Izzo, Amanda; Reiner, Robert C.; Walker, Hannah; Stankowich, Theodore
Nature Communications, 2014
Mapped the presence, extent and body location of striping across every living horse, ass and zebra species and subspecies, then tested it against geographic data for each competing hypothesis: predator distribution, woodland cover, temperature, range overlap with conspecifics, and the distribution of tabanid and tsetse biting flies.
- Studied in
- Equus
- Sample size
- all extant equid species and subspecies, mapped across their ranges
Striping was consistently and strongly associated only with the distribution of biting flies. No association was found with large predator distribution, woodland cover, temperature range or social variables that would support the camouflage, confusion, thermoregulation or social-recognition hypotheses.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Biting-fly avoidance is the best-supported explanation for equid striping, and the traditional predator-focused and thermoregulatory hypotheses are not supported by the geographic pattern.
How NatureHQ reads it
The study that converted a 150-year argument into a testable comparison. Its power is in the design rather than any single measurement: five hypotheses, each making a different geographic prediction, tested against the same dataset at once. Four of them failed on their own terms.
- A comparative geographic analysis, which establishes association rather than mechanism.
- The fly-distribution data are coarse relative to the striping data, which the authors discuss.
- It does not explain how stripes deter flies, which the design cannot address.
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Zebra
Across every wild horse, ass and zebra, striping tracks one thing: where biting flies are. It shows no association with predators, woodland, temperature range or social living.
Zebra
Modelled through lion and hyena vision, zebra stripes blur into grey beyond about fifty metres in daylight — and far closer at dusk. By the time a predator can resolve them it has already found the zebra.
Published by: Nature PortfolioPublished in a Nature Portfolio journal.
Checked against Crossref on 2026-09-28, and they agree on the title, the authors and the year.
NatureHQ summarises research in its own words and does not reproduce published text. Reviewed 2026-09-03.