Why does nature create patterns? The reason patterns often appear in nature is simple: the same basic physical or chemical processes occur in many pattern substances and organisms as they form. Whether in plants and animals or rocks, foams and ice crystals, the intricate patterns that happen in nature come down to what's happening at the level of atoms and molecules.
A pattern in nature is any regularly repeated arrangement of shapes or colors. Some of the most striking examples include the six-sided arrays of rocks at Giant's Causeway in the United Kingdom, and the colorful stripes and spots on tropical fish. Patterns like these begin to form at a small scale when materials undergo processes like drying, freezing, wrinkling, diffusing and reacting. Those changes then give rise to complex patterns at a larger scale that people can see.
Imagine delicate frozen crystals on a window during winter. What creates that pattern? When water freezes, its molecules begin clustering together. Water molecules have a particular bent shape that causes them to stack into clusters as they freeze. As the cluster grows, many outside factors, including humidity and temperature, begin to affect its overall shape. If the water is freezing on a window, for example, random imperfections on the glass surface affect the stacking and create the larger pattern.
But scientists do not always know the purpose of a pattern, or even if there is one. The molecular processes involved are simple enough that they might generate a pattern by coincidence.