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Proceedings. Biological sciences2020; 287(1933); 20201521; doi: 10.1098/rspb.2020.1521

Zebra stripes, tabanid biting flies and the aperture effect.

Abstract: Of all hypotheses advanced for why zebras have stripes, avoidance of biting fly attack receives by far the most support, yet the mechanisms by which stripes thwart landings are not yet understood. A logical and popular hypothesis is that stripes interfere with optic flow patterns needed by flying insects to execute controlled landings. This could occur through disrupting the radial symmetry of optic flow via the aperture effect (i.e. generation of false motion cues by straight edges), or through spatio-temporal aliasing (i.e. misregistration of repeated features) of evenly spaced stripes. By recording and reconstructing tabanid fly behaviour around horses wearing differently patterned rugs, we could tease out these hypotheses using realistic target stimuli. We found that flies avoided landing on, flew faster near, and did not approach as close to striped and checked rugs compared to grey. Our observations that flies avoided checked patterns in a similar way to stripes refutes the hypothesis that stripes disrupt optic flow via the aperture effect, which critically demands parallel striped patterns. Our data narrow the menu of fly-equid visual interactions that form the basis for the extraordinary colouration of zebras.
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Publication Date: 2020-08-19 PubMed ID: 32811316PubMed Central: PMC7482270DOI: 10.1098/rspb.2020.1521Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research article explores why zebras have stripes by examining the hypothesis that the stripes serve to prevent attacks from biting flies. The researchers suggest that the stripes might interfere with the insects’ flight patterns and affect their visibility. The study focused on having horses wear different patterns to observe the behavior of the flies around these setups, providing a more realistic scenario. The data indicated that flies avoid the striped and checked areas more so than the grey areas.

Research Problem and Objective

  • The article’s primary focus is to understand the zebra’s particular colouration. For many years, it has been believed that their stripes help deter attacks from biting flies. Still, there was a lack of clarity regarding how these stripes help in achieving this.
  • This research aimed to bring more evidence concerning this hypothesis. The researchers investigated whether the stripes interfere with the biting flies’ visual perception and rendered them unable to make a successful landing on the zebra’s body.

The conducted experiments

  • The experiment involved observing tabanid fly behaviour around horses wearing differently patterned rugs.
  • The patterns included were checked, striped and grey. The choice of patterns encompassed the spectrum – from the more complex to the simple. Stripes and checks represent mixed patterns, engaging lines, and squares, while the grey pattern represents a homogenous, unbroken and plain design.
  • Such an experiment provided a realistic assessment, mimicking the natural interaction between the flies and zebras in the wild.

Results and Conclusions

  • The study found that flies avoided landing on, flew faster near, and did not approach as close to striped and checked rugs compared to grey ones.
  • The then-current belief was that stripes could create an ‘aperture effect’, disrupting the optic flow of the flies, and was refuted in this study as even the checked patterns had similar repelling results as the stripes, removing the exclusivity of parallel pattern’s effect on tabanid flies.
  • This eased the path in understanding fly-zebra visual interactions, providing clearer insight into how the zebra’s colouration mechanistically deters flies. The study, therefore, helped unpack some of the mysteries associated with the zebra’s pattern.

Cite This Article

APA
How MJ, Gonzales D, Irwin A, Caro T. (2020). Zebra stripes, tabanid biting flies and the aperture effect. Proc Biol Sci, 287(1933), 20201521. https://doi.org/10.1098/rspb.2020.1521

Publication

Proceedings. Biological sciences
ISSN: 1471-2954
NlmUniqueID: 101245157
Country: England
Language: English
Volume: 287
Issue: 1933
Pages: 20201521
PII: 20201521

Researcher Affiliations

How, Martin J
  • School of Biological Sciences, University of Bristol, 24 Tyndall Avenue, Bristol BS8 1TQ, UK.
Gonzales, Dunia
  • School of Biological Sciences, University of Bristol, 24 Tyndall Avenue, Bristol BS8 1TQ, UK.
Irwin, Alison
  • School of Biological Sciences, University of Bristol, 24 Tyndall Avenue, Bristol BS8 1TQ, UK.
Caro, Tim
  • School of Biological Sciences, University of Bristol, 24 Tyndall Avenue, Bristol BS8 1TQ, UK.
  • Center for Population Biology, University of California, Davis, CA 95616, USA.

MeSH Terms

  • Animals
  • Color
  • Cues
  • Diptera
  • Flight, Animal
  • Insect Bites and Stings
  • Pigmentation

Conflict of Interest Statement

We declare we have no competing interests.

References

This article includes 33 references
  1. Ruxton GD. The possible fitness benefits of striped coat coloration for zebra. Mamm. Rev. 32, 237–244.
    doi: 10.1046/j.1365-2907.2002.00108.xgoogle scholar: lookup
  2. Melin AD, Kline DW, Hiramatsu C, Caro T. Zebra Stripes through the Eyes of Their Predators, Zebras, and Humans.. PLoS One 2016;11(1):e0145679.
    doi: 10.1371/journal.pone.0145679pmc: PMC4723339pubmed: 26799935google scholar: lookup
  3. Caro T. Zebra stripes. Chicago, IL: University of Chicago Press.
  4. Hayward MW, Kerley GIH. Prey preferences of the lion (Panthera leo). J. Zool. 267, 309–322.
    doi: 10.1017/S0952836905007508google scholar: lookup
  5. Cobb A, Cobb S. Do zebra stripes influence thermoregulation?. J. Nat. Hist. 53, 863–879.
    doi: 10.1080/00222933.2019.1607600google scholar: lookup
  6. Horváth G, Pereszlényi Á, Száz D, Barta A, Jánosi IM, Gerics B, Åkesson S. Experimental evidence that stripes do not cool zebras.. Sci Rep 2018 Jun 19;8(1):9351.
    doi: 10.1038/s41598-018-27637-1pmc: PMC6008466pubmed: 29921931google scholar: lookup
  7. Waage JK. How the zebra got its stripes: biting flies as selective agents in the evolution of zebra coloration. J. Entomol. Soc. Southern Africa 44, 351–358.
  8. Gibson G. Do tsetse flies see zebras? A field study of the visual response of tsetse to striped targets. Physiol. Entomol. 17, 141–147.
    doi: 10.1111/j.1365-3032.1992.tb01191.xgoogle scholar: lookup
  9. Brady J, Shereni W. Landing responses of the tsetse fly Glossina morsitans morsitans Westwood and the stable fly Stomoxys calcitrans (L.) (Diptera: Glossinidae & Muscidae) to black-and-white patterns: a laboratory study. Bull. Entomol. Res. 78, 301–311.
    doi: 10.1017/S0007485300013067google scholar: lookup
  10. Egri A, Blahó M, Kriska G, Farkas R, Gyurkovszky M, Akesson S, Horváth G. Polarotactic tabanids find striped patterns with brightness and/or polarization modulation least attractive: an advantage of zebra stripes.. J Exp Biol 2012 Mar 1;215(Pt 5):736-45.
    doi: 10.1242/jeb.065540pubmed: 22323196google scholar: lookup
  11. Horváth G, Pereszlényi Á, Åkesson S, Kriska G. Striped bodypainting protects against horseflies.. R Soc Open Sci 2019 Jan;6(1):181325.
    doi: 10.1098/rsos.181325pmc: PMC6366178pubmed: 30800379google scholar: lookup
  12. 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 2019;14(10):e0223447.
    doi: 10.1371/journal.pone.0223447pmc: PMC6776349pubmed: 31581218google scholar: lookup
  13. Caro T, Argueta Y, Briolat ES, Bruggink J, Kasprowsky M, Lake J, Mitchell MJ, Richardson S, How M. Benefits of zebra stripes: Behaviour of tabanid flies around zebras and horses.. PLoS One 2019;14(2):e0210831.
    doi: 10.1371/journal.pone.0210831pmc: PMC6382098pubmed: 30785882google scholar: lookup
  14. How MJ, Zanker JM. Motion camouflage induced by zebra stripes.. Zoology (Jena) 2014 Jun;117(3):163-70.
    doi: 10.1016/j.zool.2013.10.004pubmed: 24368147google scholar: lookup
  15. Baird E, Boeddeker N, Ibbotson MR, Srinivasan MV. A universal strategy for visually guided landing.. Proc Natl Acad Sci U S A 2013 Nov 12;110(46):18686-91.
    doi: 10.1073/pnas.1314311110pmc: PMC3831993pubmed: 24167269google scholar: lookup
  16. Harris RA, O'Carroll DC, Laughlin SB. Contrast gain reduction in fly motion adaptation.. Neuron 2000 Nov;28(2):595-606.
    doi: 10.1016/S0896-6273(00)00136-7pubmed: 11144367google scholar: lookup
  17. Hildreth EC, Koch C. The analysis of visual motion: from computational theory to neuronal mechanisms.. Annu Rev Neurosci 1987;10:477-533.
    doi: 10.1146/annurev.ne.10.030187.002401pubmed: 3551763google scholar: lookup
  18. Wuerger S, Shapley R, Rubin N. ‘On the visually perceived direction of motion’ by Hans Wallach: 60 years later. Perception 25, 1317–1367.
    doi: 10.1068/p251317google scholar: lookup
  19. Troscianko T, Benton CP, Lovell PG, Tolhurst DJ, Pizlo Z. Camouflage and visual perception.. Philos Trans R Soc Lond B Biol Sci 2009 Feb 27;364(1516):449-61.
    doi: 10.1098/rstb.2008.0218pmc: PMC2674079pubmed: 18990671google scholar: lookup
  20. Krapp HG, Hengstenberg R. Estimation of self-motion by optic flow processing in single visual interneurons.. Nature 1996 Dec 5;384(6608):463-6.
    doi: 10.1038/384463a0pubmed: 8945473google scholar: lookup
  21. Götz KG. [The optical transfer properties of the complex eyes of Drosophila].. Kybernetik 1965 Jun;2(5):215-21.
    doi: 10.1007/BF00306417pubmed: 5839008google scholar: lookup
  22. Horváth G, Pereszlényi Á, Egri Á, Fritz B, Guttmann M, Lemmer U, Gomard G, Kriska G. Horsefly reactions to black surfaces: attractiveness to male and female tabanids versus surface tilt angle and temperature.. Parasitol Res 2020 Aug;119(8):2399-2409.
    doi: 10.1007/s00436-020-06702-7pmc: PMC7366589pubmed: 32424552google scholar: lookup
  23. Horváth G, Szörényi T, Pereszlényi Á, Gerics B, Hegedüs R, Barta A, Åkesson S. Why do horseflies need polarization vision for host detection? Polarization helps tabanid flies to select sunlit dark host animals from the dark patches of the visual environment.. R Soc Open Sci 2017 Nov;4(11):170735.
    doi: 10.1098/rsos.170735pmc: PMC5717639pubmed: 29291065google scholar: lookup
  24. Meglič A, Ilić M, Pirih P, Škorjanc A, Wehling MF, Kreft M, Belušič G. Horsefly object-directed polarotaxis is mediated by a stochastically distributed ommatidial subtype in the ventral retina.. Proc Natl Acad Sci U S A 2019 Oct 22;116(43):21843-21853.
    doi: 10.1073/pnas.1910807116pmc: PMC6815168pubmed: 31591223google scholar: lookup
  25. Caro T, Izzo A, Reiner RC Jr, Walker H, Stankowich T. The function of zebra stripes.. Nat Commun 2014 Apr 1;5:3535.
    doi: 10.1038/ncomms4535pubmed: 24691390google scholar: lookup
  26. Britten KH, Thatcher TD, Caro T. Zebras and Biting Flies: Quantitative Analysis of Reflected Light from Zebra Coats in Their Natural Habitat.. PLoS One 2016;11(5):e0154504.
    doi: 10.1371/journal.pone.0154504pmc: PMC4880349pubmed: 27223616google scholar: lookup
  27. Blaho M, Egri A, Bahidszki L, Kriska G, Hegedus R, Akesson S, Horvath G. Spottier targets are less attractive to tabanid flies: on the tabanid-repellency of spotty fur patterns.. PLoS One 2012;7(8):e41138.
    doi: 10.1371/journal.pone.0041138pmc: PMC3410892pubmed: 22876282google scholar: lookup
  28. Bard JBL. A unity underlying the different zebra striping patterns. J. Zool. 183, 527–539.
    doi: 10.1111/j.1469-7998.1977.tb04204.xgoogle scholar: lookup
  29. Marcon L, Sharpe J. Turing patterns in development: what about the horse part?. Curr Opin Genet Dev 2012 Dec;22(6):578-84.
    doi: 10.1016/j.gde.2012.11.013pubmed: 23276682google scholar: lookup
  30. Turing A. The chemical basis of morphogenesis. Phil. Trans. R. Soc. B 237, 37–72.
    doi: 10.1098/rstb.1952.0012google scholar: lookup
  31. Caro T, Mallarino R. Coloration in Mammals.. Trends Ecol Evol 2020 Apr;35(4):357-366.
    doi: 10.1016/j.tree.2019.12.008pubmed: 31980234google scholar: lookup
  32. Olaide OY, Tchouassi DP, Yusuf AA, Pirk CWW, Masiga DK, Saini RK, Torto B. Zebra skin odor repels the savannah tsetse fly, Glossina pallidipes (Diptera: Glossinidae).. PLoS Negl Trop Dis 2019 Jun;13(6):e0007460.
    doi: 10.1371/journal.pntd.0007460pmc: PMC6586361pubmed: 31181060google scholar: lookup
  33. How MJ, Gonzales D, Irwin A, Caro T. Zebra stripes, tabanid biting flies and the aperture effect.. Proc Biol Sci 2020 Aug 26;287(1933):20201521.
    doi: 10.5061/dryad.18931zctkpmc: PMC7482270pubmed: 32811316google scholar: lookup

Citations

This article has been cited 8 times.
  1. Caro T, Fogg E, Stephens-Collins T, Santon M, How MJ. Why don't horseflies land on zebras?. J Exp Biol 2023 Feb 15;226(4).
    doi: 10.1242/jeb.244778pubmed: 36700395google scholar: lookup
  2. Cox EG, Bell R, Greer RM, Jeffcott LB. A survey on the use of rugs in Australian horses. Aust Vet J 2023 Jan;101(1-2):9-26.
    doi: 10.1111/avj.13219pubmed: 36437593google scholar: lookup
  3. de Angeli Dutra D, Poulin R, Ferreira FC. Evolutionary consequences of vector-borne transmission: how using vectors shapes host, vector and pathogen evolution. Parasitology 2022 Nov;149(13):1667-1678.
    doi: 10.1017/S0031182022001378pubmed: 36200511google scholar: lookup
  4. Takács P, Száz D, Vincze M, Slíz-Balogh J, Horváth G. Sunlit zebra stripes may confuse the thermal perception of blood vessels causing the visual unattractiveness of zebras to horseflies. Sci Rep 2022 Aug 4;12(1):10871.
    doi: 10.1038/s41598-022-14619-7pubmed: 35927437google scholar: lookup
  5. Spence C, Van Doorn G. Visual communication via the design of food and beverage packaging. Cogn Res Princ Implic 2022 May 12;7(1):42.
    doi: 10.1186/s41235-022-00391-9pubmed: 35551542google scholar: lookup
  6. Pereszlényi Á, Száz D, Jánosi IM, Horváth G. A new argument against cooling by convective air eddies formed above sunlit zebra stripes. Sci Rep 2021 Aug 4;11(1):15797.
    doi: 10.1038/s41598-021-95105-4pubmed: 34349136google scholar: lookup
  7. Ireland HM, Ruxton GD. Zebra stripes: the questions raised by the answers. Biol Rev Camb Philos Soc 2025 Dec;100(6):2660-2680.
    doi: 10.1111/brv.70063pubmed: 40745963google scholar: lookup
  8. Tosetto L, Hart NS, Ryan LA. Dazzling damselfish: investigating motion dazzle as a defence strategy in humbug damselfish (Dascyllus aruanus). PeerJ 2024;12:e18152.
    doi: 10.7717/peerj.18152pubmed: 39346079google scholar: lookup
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