Marcus du Sautoy describes how fractal geometry can be used to describe natural objects, and how it is used in digital animation. Trees use the simple rule of trying to maximize surface area, and this is something that can be simulated mathematically to give a very realistic result. Mandelbrot explored this fractal property of infinite complexity in his work, which was then taken up by a digital animator to create extremely life-like surfaces in his films. Teacher notes: Use as an enrichment clip during a series of lessons on shape or symmetry, or during lessons on pattern and following rules. Students can then be asked to explore other fractals, and find animations of them. They could also work to produce patterns based on the Sierpinski triangle.