In 1952, Alan Turing wrote a mathematical paper on pattern formation in biology that was for decades regarded as a curiosity and is now acknowledged as a major contribution to morphogenesis, pattern formation in living systems. Purely mathematically, Turing deduced the patterns that would form in reaction-diffusion systems, ie where a chemical diffusing through a medium, meets another chemical, reacting and continuing to diffuse. The local reaction can change the diffusing pattern at the wave front. Sometimes the product of the reaction can temporarily inhibit the diffusion.
The result is complexity, rather as complexity results from iterative equations in fractals. Turing-type patterns exist in nature, in brain corals for instance. My paint wrinkles resemble brain coral very closely. I particular like the bifurcations that appear in these systems. The pomacanthus fish shows this very nicely.
Turing has many illustrious achievements to his name. Now I realise he is also the man who made even watching paint dry interesting.