Aquatic regions house numerous species of plants and animals, both large and small.
In fact, this is where life began billions of years ago when amino acids first started to come together. Without water, most life forms would be unable to sustain themselves and the Earth would be a barren, desert-like place. Although water temperatures can vary widely, aquatic areas tend to be more humid and the air temperature on the cooler side. The following sections describe the characteristics of these three freshwater zones. These regions range in size from just a few square meters to thousands of square kilometers.