These mathematically inspired designs like leopard spots and tiger stripes are as interesting as they are intricate. But how did animals get their spots, stripes, and everything in between? In Turing’s theory, some of these chemicals then activate pigment-producing cells, which creates spots. However, computer simulations based on Turing’s idea created spots that were blurrier than those found in nature. Bottom: Simulated hexagon and stripe patterns obtained by diffusiophoretic assembly of two types of cells on top of the chemical patterns.