The Pirate Lab (part 1)

Question: Do pirate patches help your eyes adjust to the dark faster? Research Info: Read the following, then answer a few questions. Is This the Real Reason Why Pirates Wore Eye Patches?Between 1700 and 1725, the Caribbean was a relatively lawless place with numerous merchant ships traversing the high seas with no authorities to protect them. These factors helped to make this period the golden age of piracy. It turns out that many common beliefs about pirates are not true. They didn’t walk the plank, they rarely buried treasure, and they weren’t always criminals. The life of a pirate was also often better than the life of most merchant seamen and naval personnel at the time. One thing that is true about pirates, however, is that at least some of them wore eye patches. This introduces the question, why did they wear them? One plausible answer reveals that pirates may have been quite smart when it was required.Common Theories About Why Pirates Wore Eye patchesA common theory is that pirates wore eye patches because they had lost one eye in battle. This makes sense, and there probably were many maimed pirates who wore eye patches.Another recent hypothesis is that pirates used the eye patch to protect their dark-adapted vision. This would have been in case they needed to go underdeck to continue a fight after having taken the deck of a ship.Illumination on Night Vision Versus Day VisionThe human eye can adapt rapidly from low light to daylight conditions, but it takes as much as 25 minutes for the eye to adjust from daylight conditions to low light levels. The reason for this is that there are two types of light receptive cells in the eye, cones and rods. Cones are the predominant light sensitive cells for day-time vision. They are also responsible for our color vision. These cells have evolved to adapt quickly to changing light conditions. Both cones and rods play a role in night vision and day vision, but rods are the primary light sensitive cells for night vision. Rods can detect extremely low amounts of light, even a single photon, but they are less effective under high levels of illumination.When lighting conditions change, cones will quickly adapt while rods will take longer to adjust. Thus, it takes a while for our night vision to fully activate because it takes a while for the rods to adjust so that they can take over from the cones as the primary photoreceptors. One possible evolutionary reason for this is that humans are primarily daytime creatures, so our vision needs to be very receptive to day-time levels of illumination.The Advantage of the Pirate Eye Patch and Promptings of Pirate LoreThe fact that it takes the eyes longer to adjust to decreased illumination than to increased illumination has implications for combat situations, especially those which require navigating between areas of daytime lighting and areas of relative darkness. Pirates, when they boarded ships, would take the deck and then they might have to go beneath the deck to finish a fight. On the other hand, their ship might get boarded and they might get driven below deck by enemy marines. While going underdeck, combat would become more difficult since it would take a while for their eyes to adjust to the darkness so that they could see their attackers.One possibility is that pirates, while on deck, would wear the eyepatch over a dark-adapted eye and use their daylight-adapted eye to fight. When they went below deck, they would use their dark-adapted eye. This would have given the pirates a fearsome advantage over their opponents since they would be able to see more clearly than their adversaries and be able to surprise them. True or False: Pirates really wore eyepatches. True False The answer was not in the text. According to the text, if you walk from a bright room into a dark room, about how long does it take for you eyes to adjust? You can see immediately 5 minutes 25 minutes 60 minutes Why do researchers think patches could have helped pirates? It helped to protect their eyes from parrot pecks It helped their eyes adapt to the dark quickly It helped their eyes adapt to the light quickly They looked wicked cool Match the functions to the part. Rods nighttime vision Cones daytime vision You are going to be testing this the usefulness of patches at home tomorrow. How do you THINK you would test this at home? What will you measure? Do your best on this question-- we will discuss it during our synchronous time tomorrow!