It started as an adventure. Some college buddies tried their own version of a "survivor" experience. During summer vacation, they were dropped off on an uninhabited tropical island, with minimal supplies. They would be picked up in a few days. The island was hot and dry, and they discovered that there was no fresh water.

They knew that coconuts could provide fluids in the form of coconut "milk." But one group member hated coconuts. He figured he'd get his fluids by drinking salt water. At first, he was fine - although he was thirstier than his friends. Then, he became nauseated and weak. His condition worsened quickly. Soon he was seriously ill - with dizziness, headaches, and an inability to concentrate. His friends began to panic. What was happening? As you read the chapter, look for clues to help you explain the reason for the survivalist's illness. Then, solve the mystery.