‘Nature's patterns’ explores symmetry in the natural world. Bilateral symmetry in organisms has been shown to be controlled genetically. However, anatomical symmetry is broken in some organ systems. Animal gaits display symmetry in space, time, and permutational symmetries of the legs. Sand dune formation is due to symmetry breaking, with different broken symmetries giving rise to different shapes. Galactic spirals are often close to the logarithmic spiral, which has a continuous family of symmetries. Johannes Kepler deduced that the crystal lattice of ice at the heart of a snowflake creates a hexagonal ‘seed’ which gives rise to threefold symmetry.