The heart of the Everglades is water and without the flow of fresh, clean water from Lake Okeechobee, the area would cease to exist. An intimate relation between surface water and ground water is crucial in the creation of the lower wetlands system. This relation involves three elements: rising sea level, solution which is acidic rain water that dissolves through limestone and hydroperiod, the number of days South Florida can be expected to flood. Rainfall also contributes by dissolving some of the rock setting off a chemical reaction that brought the groundwater in contact with land's surface. This in turn eventually created a valley that provided a shallow drainage slough (9-10).
Finally, fire is the last crucial element in the development of the Everglades falling within two broad categories, superficial and deep. Superficial fires occur during the wet-weather cycles and are primarily the result of thunderstorm lightning strikes. These fires play a major role in the maintenance of plant communities since they inhibit the invasion by woody plants of grassy marshes (Everglades 5: 434). Deep fires occur less frequently than superficial but tend to cause more damage. The dry conditions allow these fires to kill even fire-resistant species. These close associations between fire and hydroperiod have had a profound effect on the evolution of the mature Everglades ecosystem (McCally 20-21).
The Everglades can be described as a series of vast swamps, poisonous lagoons and huge marshes and yet is the home to a variety of species. It also has the largest concentration of saw grass, a place where many animals call home. Some animals that are found specifically in the Everglades are adapted to the dry and wet seasons. For example, alligators build their nests at the high water level because if more water is released than needed, their nests will become flooded and destroyed (Douglas 9-11; Uhler 5).