Zebra stripes: an interspecies signal to facilitate mixed-species herding?

This is the authors' abstract. We don't add key points for this paper.

Many diverse hypotheses have been suggested for the stripes of the plains zebra Equus quagga. We propose a new hypothesis that this adaptation represents visual interspecies signalling to facilitate mixed-species herding. Mixed-species herds likely offer enhanced protection from predation. They can also facilitate feeding for both zebra and other grazers, as zebra are hindgut fermenters and prefer different foliage to associating ruminants. This mechanism, uniquely, can explain why stripes might evolve in zebra and not in other large African grazers (because of their different digestive strategy). This signalling mechanism is not exclusive, however, and could operate alongside one or more of the previously postulated mechanisms selecting for zebra stripes.