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Why do Zebras have stripes? Are zebras white with black stripes or black with white?

We’ll get to the eternal question of whether zebras are black with white stripes or white with black stripes in just a little bit.  Let’s focus in on why they have the stripes in the first place!

There are five main theories as to why zebras are striped:  camouflage, confusion, recognition, cooling, and repellant…

1. Pure Camouflage:  It has been proposed that one of the reasons as to why zebras have stripes is because they use these color patterns to hide.  Supposedly, the vertical black and white stripes help the zebra blend in with things like tall grasses.  It’s been said (incorrectly) that since the zebra’s predators are colorblind, they cannot distinguish the long blades of grass from the long black and white stripes on zebras.

Unfortunately, this theory has scant evidence and support, and has plenty of arguments to the contrary:

First, zebras are often located outside the confines of long grasses, where their stripes, if solely for this purposes, would serve no use.

Secondly, their predators are partially colorblind, not fully colorblind.  This means that black and white stripes may actually hinder the zebra’s ability to hide in green or tan grass; at least during the day.

Zebra head on white background by @Doug88888, on FlickrFinally, many zebras have horizontal stripes in many places.  Hence, these stripes may actually catch the eyes of a predator noticing the awkward black and white horizontal stripes moving across vertical blades of green grass.

2. Confusion: As I just mentioned, I’m sure you noticed in nature shows that zebras are often-times in wide open, exposed areas.  This means there are no tall grasses to help “camouflage” them and therefore stripes would likely serve little use for that purpose.

Nevertheless, the stripes on an individual animal or the mass congregation of striped zebras may induce a type of “dazzle camouflage”.    Dazzle camouflage may help make it more difficult for predators to estimate any one animal’s speed and direction, hindering the predator’s ability to catch any one zebra.  Note that dazzle camouflage isn’t the type of camouflage used to hide behind or on something while standing still in order to not get noticed in the first place.  Instead, this camouflage is used to confuse movement, direction, and speed when fully exposed.

This defense method was also used by certain ships in WWI and WWII and is being looked at again for modern military use.

3. Recognition:  Certain researchers and zoologists believe that zebras use stripes to recognize one another since each pattern is quite unique.  Again, a lack of concrete evidence makes this hypothesis questionable at the moment as some studies relied on stuffed animals to reach this conclusion (without taking other important factors into consideration).

4. Cooling:  The difference in the absorption and reflection of heat by black and white stripes may actually create a cooling effect on the animal.  This seems to have more to do with differences in fat distribution beneath white and black stripes than with the color of the stripes itself.   Again, while feasible, this theory has yet to be definitively proven to be the case.

5. Repellant:  No, not lion repellant – an insect repellant!  Scientists in Hungary have proven that the striped pattern is excellent at getting rid of pesky flies.  Why bother getting rid of them?  Besides the unpleasant bites, many of the biting insects transmit terrible diseases that may hinder an animal’s ability to survive.  However, the research does have its flaws.  Namely: it was conducted on inanimate objects (this means that other factors that may attract flies, such as smells, may outweigh the benefits of the stripes in the wild for this purpose).

So there you have it: many theories but no definitive answer!

Are zebras white with black stripes or the other way round?

As for whether or not zebras are black with white stripes or black with white stripes, that’s like asking me: which came first, the chicken or the egg?

Well, no, not really.  In this case, we actually have a pretty good case for the correct answer (although not definitive by any means).  Zebras are black with white stripes according to our best (but scant) understanding of zebra embryology.

Questions asked by Facebook

Answered by Artem Cheprasov

References below.

Bard, J. B. L. (1977). A unity underlying the different zebra striping patterns. Journal of Zoology 183:527–39

Calderone JB, Reese BE, & Jacobs GH (2003). Topography of photoreceptors and retinal ganglion cells in the spotted hyena (Crocuta crocuta). Brain, behavior and evolution, 62 (4), 182-92 PMID: 14573992

Egri A, Blahó M, Kriska G, Farkas R, Gyurkovszky M, Akesson S, & Horváth G (2012). Polarotactic tabanids find striped patterns with brightness and/or polarization modulation least attractive: an advantage of zebra stripes. The Journal of experimental biology, 215 (Pt 5), 736-45 PMID: 22323196

Kingdon, Jonathan. (1979). East African Mammals: An Atlas of Evolution in Africa, Volume 3, Part B: Large Mammals. Chicago: University of Chicago Press

Prothero, Donald. (2002). Horns, Tusks, and Flippers: The Evolution of Hoofed Mammals. Baltimore: John Hopkins University Press

Steves M, et al, (2011). Motion dazzle and camouflage as distinct anti-predator defenses. BMC Biology, 9 (1):81

About The Author:


Dr. Artem Cheprasov was born in St. Petersburg, Russia. He then moved to the U.S. when he was a little boy. So no, he is not a spy. Or is he? He finished his studies in veterinary medicine at the top 10% of his class, conducted research, and discovered a cool mathematics algorithm; but we cannot confirm this as both Washington and Moscow have refused to comment on this matter either because he really is a spy or more likely because they have no idea who he even is.

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