Turing’s centenial flowers

Image: Wikimedia Commons.

Image: Wikimedia Commons.

When flowers are mentioned in the context of Alan Turing (OBE, FRS, maths genius, tortured soul, ‘an enigma inside a colossus’, and one of the main members of the group of Bletchley Park code-breakers who were instrumental in decoding the Nazis’ Enigma code and thereby credited with considerably shortening the Second World War and saving many thousand of lives), the more knowledgeable may think of Tommy Flowers. Tommy Flowers (MBE) worked alongside Turing and designed the Colossus computer used at Bletchley to help solve encrypted German messages. But this item concerns flowers of a more botanical kind: Sunflowers. Amongst Turing’s many interests was pattern formation – morphogenesis – which he expounded upon in one of his several seminal papers. In particular, towards the end of his life, he was interested in the patterns on sunflower heads and believed they featured Fibonacci numbers. The Fibonacci sequence is named in honour of Leonard of Pisa (aka Fibonacci) and is the numerical sequence that proceeds 0, 1, 1, 2, 3, 5, 8, 13… (each number is the sum of the previous two), and which is represented in a range of biological phenomena. Sadly – and tragically – Turing died in 1954 before he could complete this work. But, by way of celebrating the centenary of his birth, the Turing Sunflower Project was conceived, which aimed to collect sufficient data to put Turing’s (and other scientists’) theories to the test. And the good news is that ‘Alan Turing was right’: ‘sunflower spirals clearly show a mathematical sequence in most cases, according to early results’. The results will be published shortly, according to Jonathan Swinton, one of the main instigators behind the project. And in their own way ‘Turing’s sunflowers’ may even rival those of another ‘troubled soul’, the Dutch painter Vincent van Gogh – also believed to have taken his own life when the balance of his mind was probably disturbed. If you now have a yearning to find out more about phyllotaxy (which, despite its prefix, is not just about leaves!), may I recommend Adler et al.’s review article ‘A history of the study of phyllotaxis’? For more on Turing, try Andrew Hodges’ ‘The Alan Turing Home Page’.

[I wish to thank the following for help in developing this item: Jeff Moorby (who started this particular ball rolling in the first place!), the Annals’ own Dave Frost and Pat Heslop-Harrison, and that fabulous Irish cabbie, Phil O’Taxis]

Nigel Chaffey

Nigel is a botanist and full-time academic at Bath Spa University (Bath, near Bristol, UK). As News Editor for the Annals of Botany he contributes the monthly Plant Cuttings column to that august international botanical organ. His main goal is to inform (hopefully, in an amusing, educational, and entertaining way...) about plants and plant-people interactions.

1 Response

  1. Pat says:

    If you still believe that Turing was a “tortured soul” who took his own life you should read this article on the BBC:


    “The day of the trial was by no means disagreeable.

    “Whilst in custody with the other criminals, I had a very agreeable sense of irresponsibility, rather like being back at school.”

    Turing had a brilliantly analytic mind and I don’t think he mistook the state of society at the time for the way things should be. He was not a victim.

    He was, however, as I have been, a careless experimenter who took his life in his hands during the pursuit of an interesting hobby. One can get carried away with one’s enthusiasms even when potent poisons are being used.

    “Turing was hounded,” he told the BBC, adding: “Yet he remained cheerful and humorous.”