What is the name of the chemical pattern formation model developed by Turing?

The chemical pattern-formation model developed by Alan Turing is a reaction–diffusion system. In this model, chemical substances react locally and diffuse through space, and their interaction can produce organized patterns from an initially uniform or nearly uniform state.

Turing described the idea in his 1952 paper “The Chemical Basis of Morphogenesis.” He proposed that an activator chemical could promote its own production while an inhibitor suppressed it, with the two substances spreading at different rates. Surprisingly, diffusion—which normally smooths out differences—could under the right conditions amplify particular spatial patterns.

The resulting mathematical models can generate spots, stripes, waves, spirals, and other structures. These are often called Turing patterns, while the instability that creates them is called Turing instability. The model has influenced theoretical biology and studies of animal pigmentation, limb development, and other forms of morphogenesis. It is a model or proposed mechanism, not a claim that every biological pattern is produced by exactly the same chemical process.