Skin colour patterns in animals arise from microscopic interactions among coloured cells that obey equations discovered decades ago by the great mathematician Alan Turing. We recently showed that the skin colour patterning in ocellated lizard is at odd with that time- and space-continuous mechanism.
We demonstrated that the skin scales form spatially discrete units that are either green or black and switch colour depending on the colours of their neighbours. This corresponds to a cellular automaton (CA), a computational system invented in 1948 by John von Neumann. Using histology, numerical simulations and mathematical derivation, we identified that skin thickness variation generated by 3D morphogenesis restricts diffusion at the borders of scales and causes the Turing mechanism to transform into the von Neumann CA, allowing biology-driven research to link, for the first time, the work of these two mathematical giants.
The TV report on the evening News of the Swiss Television (RTS):
https://www.rts.ch/info/sciences-tech/8539335-des-chercheurs-genevois-percent-le-mystere-des-motifs-d-un-lezard.html
The TV report on Italian TV: https://www.youtube.com/watch?v=fsqnRmzWwC4
Read the article in NATURE