Scientists Prove Alan Turing's Tiger Stripe Theory

Posted on February 20, 2012

Researchers from King's College London have provided experimental evidence confirming Alan Turing's theory of how biological patterns such as tiger stripes or leopard spots are formed. Turing - best known for his contributions to computer science - put forward a theory in the 1950s that regular repeating patterns in biological systems are generated by a pair of morphogens that work together as an activator and inhibitor.

Researchers were able to confirm this theory in the lab. Carrying out experiments in mouse embryos, the team identified the pair of morphogens working together to influence where each ridge in the roof of the mouth of mice will be formed. The researchers identified the specific morphogens involved in the process as FGF (Fibroblast Growth Factor) and Shh (Sonic Hedgehog). The researchers discovered that when these morphogens' activity is increased or decreased, the pattern of the ridges in the mouth palate are affected in ways predicted by Turing's equations.

Dr Jeremy Green from the Department of Craniofacial Development at King's Dental Institute says, "Regularly spaced structures, from vertebrae and hair follicles to the stripes on a tiger or zebrafish, are a fundamental motif in biology. There are several theories about how patterns in nature are formed, but until now there was only circumstantial evidence for Turing's mechanism. Our study provides the first experimental identification of an activator-inhibitor system at work in the generation of stripes - in this case, in the ridges of the mouth palate."

Dr. Green explains the study and Turing's theory in the video below. Around the 2:50 mark you see software showing a very simple starting condition (resembling a tiger stripe) organizing into a more complex looking design. Take a look:

ANIMALS