If you were stuck on an island what would be the one object you would bring? I am sure many of you have heard this question before, but how do you survive on a deserted island? The main survival tactic I noticed when reading articles was obviously attempt to find a water source. Without water your body will not function properly, and your odds of surviving will decrease severely. Additionally, I also noticed that 
many online entries stated not to drink the the sea or ocean water. An interesting fact is that “for every drop of sea water you drink, you need 3 times the amount of pure water” (WikiHow). All the salt in ocean water can easily dehydrate your body, and would make living on the island so much harder.
Another important survival tip is to gather every bit of object on your body, and the people around you (if you are not alone). This allows you to have a pack of object that you can always go to if you or the people that are present need anything. Interestingly, one can hollow out a coconut and use it for cooking. Try to to cook vegetables inside, or anything around you because food is obviously a necessity.
This step might involve a bit of geometry, but try to make the best fort as possible. You need a place to cover yourself from the outside environment, and a good place to stay can help you maintain your health. There are so many ways to help yourself survive on an island, but the most important is stay focused and be creative. It is time like these where imagination is needed.
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This post reminded me of the movie Life of Pi which is about a boy stranded on a boat with a tiger. The tiger is what keeps him alive while he is lost at sea because he is consciously aware of feeding him and staying awake from the tiger so it does not kill him. In the end the boy survived because of the tiger. He was his motivation to live and I think you need motivation when you are in a situation like this. I agree with the comment above that I would prefer a companion instead of an object because you have company and someone constantly reminding you to survive and stay strong. I wasn’t aware that coconuts could hydrate you, so that is very interesting! I know that coconut juice is very good for you, so this makes sense. Also shelter is an important part of surviving on an island. You need to be able to stay warm and protect yourself from storms, disasters, or animals that may be living on that island. Here’s a link that has some important steps you need to know while being stranded on an island and how to survive.
http://www.survivenature.com/island.php
Your post reminds me of the TV show Naked and Afraid, where two people are forced to survive in the wild for 30 days. I always watched in shock as they came up with such creative ways to survive and remain somewhat comfortable. One guy made sandals out of tree bark! Another thing I learned from the show is the coconut juice can hydrate a person, so instead of going to the ocean for a drink, it is much more beneficial to go find coconuts.
Here is a link where you can learn about the show.
http://dsc.discovery.com/tv-shows/naked-and-afraid/about-the-show/about-the-show.htm
I think it would be interesting to look into the psychology of how people choose what they would bring to a desert island. If it were me, I would choose a companion instead of an object, someone who could help me survive. I feel that many people would choose to do the same. Why do we as humans feel the need for companionship over material things when in an extreme situation like the one you describe? I think this would be an interesting topic to research.