Zebras, ships and camouflage

At the end of the First World War, Britain was confronted with the prolonged attrition of its shipping fleet after years of conflict. The U-Boot, submarine ships of the German Army, were torpedoing merchant and defense vessels extremely effectively, putting at stake the control and maintenance of their shipping routes. In a attempt to reverse this situation, one answer was the so called “Dazzle Section”. In fact it was a kind of new merchant naval division painted in a very different way than previously seen before. Metal gray, classic coat in Navy ships was replaced by shocking strip patterns, usually in black and white, that altered the perception about the magnitude of the ship and the distance from wich the observer was.

The strategy was not to mimic with the background, rather show up in a distorted way by altering the perception of the position and trajectory of the ship so that the submarines missed their torpedoes. This distortion of the perspective would work only when the ship was relatively far away but this was precisely a key factor in the U-Boot attacks. The submarines must necessarily act from a distance. There were two important reasons for this: avoiding a counterattack from the ship and the fact of the torpedo needed to take a minimum run in order to be armed correctly.

Distance was important and this was exactly the weak point exploited by this type of camouflage. In the middle of the sea, without any possible cartographic reference, the detection of the position and trajectory seemed a difficult task. The identification of the type of ship allowed to know its dimensions and in this way to be able to operate certain trigonometric calculations. Determining where the ship was going, as accurately as possible, was a critical task. An error of a few dozen degrees caused the torpedo to miss. With the raised periscope, only the experience and visual sharpness of the commander allowed the shot. At that time radar or computer-aided numerical calculation simply did not exist. For this reason, human interpretation was decisive and in this point was based the deception strategy that we are talking about: disruptive camouflage.

This kind of camouflage, attributed to the marine artist Norman Wilkinson, played with the alteration of the observer’s perspective, distorting the true forms of the ship. To avoid any counterintelligence, there were no two ships with the same pattern, avoiding in this way any training of the enemy’s eye.
Despite the fact there is no evidence of the degree of usefulness of this camouflage, the fact is that it has never been possible to estimate his efficiency against U-Boot. In any case, such a way of painting soon decayed, partly due to the cost of customizing and maintaining this type of camouflage, partly due to the arrival of detection technologies, such as the radar, that made human interpretation unnecessary.

USS West Mahomet 1918. Picture of the Bureau of Ships Collection in the U.S. National Archive

 

Interestingly, a recent study of researchers from the University of California published in Nature Communations show us a link with Biomimicry. The study shows that such an approximation may have been operating for thousands of years in the relationship between zebras and mosquitoes that harass them. The study proposes that the striped pattern of zebras could be a mechanism to prevent mosquito bites in their natural environment. The contrast between the white and black stripes causes mosquitoes to miss with a higher error rate when landing on the animal. The study shows that an animal with this particular pattern reduces the number of bites in comparison with others without this pattern .

It seems that, after all, the evolution would have found a solution that allows to reduce efficiency of the attacks, very similar to the strategy used in World War naval warfare. Nature shows us solutions that we only can understand through careful observation and then apply them. We can think that these bizarre patterns share the same basic principles that nature has been operating for thousands of years. If the mosquitoes hit the zebras less because are striped, who knows if will be soon looking for a nice striped dress as a solution to the annoying mosquitoes bites that we suffer in summer.

 

Carlos Rodríguez

Biomimetics Sciences Institute