How the Leopard Gets Its Spots

The animal kingdom contains an abundance of exquisite natural patterns from the stripes of an angelfish to the spots of a leopard. But how do these arise during early development? This Catalyst article looks at Turing mechanisms as a way of explaining how patterns develop as an animal grows.

In 1952, Alan Turing proposed a mechanism to explain how animal patterns are produced. This became known as the ‘Reaction-Diffusion Model’ and is still the strongest theory for how patterning is controlled. Turing was a mathematician rather than a biologist, and is most famous for deciphering the Nazi Enigma Code during the Second World War. From this experience, he suggested that animal patterns were specified by another type of code, where diffusing molecules acted either as inhibitors or activators. A central idea is that the pattern is not predetermined but arises spontaneously as a result of the interactions between these molecules.

This article is from Catalyst: Secondary Science Review 2013, Volume 24, Issue 1.

Catalyst is a science magazine for students aged 14-19 years. Annual subscriptions to print copies of the magazine can be purchased from Mindsets.