colors of frogs.
             Coloring fulfills many purposes and is vitally important to survival. The color of a frog depends on its pigmentation, just like in humans. Color changes are created by pigment cells called chromatophores. Inside these cells, grains of pigment cause color changes by shifting their distribution. When the grains are packed together in the center of each cell, the frog is light colored. When the pigment grains spread out within each cell, the frog's color darkens and intensifies. The variety in pigmentation produces different color and pattern characteristics that are utilized by frogs in many ways, such as defense colorings and patterns that support and complement the standard mechanisms of attack or defense. Col
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