Similarly, each next number is found by adding the two numbers before it. But our findings highlight how insights from fossils and plants like clubmosses may provide vital clues in finding an answer.The order of the Fibonacci Sequence goes like this: 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144. Various hypotheses have been proposed, including to maximise the amount of light that each leaf receives or to pack seeds efficiently. This question continues to generate debate among scientists. The work also adds another piece to the puzzle of a major evolutionary question – why are Fibonacci spirals so common in plants today? It suggests that Fibonacci spirals emerged separately multiple times throughout plant evolution. They suggest that non-Fibonacci spirals were ancient in clubmosses, overturning the view that all leafy plants started out growing leaves that followed the Fibonacci pattern.įurthermore, it suggests that leaf evolution and Fibonacci spirals in clubmosses had an evolutionary history distinct from other groups of living plants today, such as ferns, conifers and flowering plants. These findings change our understanding of Fibonacci spirals in land plants. Matt Humpage/Northern Rogue Studios, CC BY-NC-ND Distinct evolutionary history Life reconstruction of fossil Asteroxylon mackiei. The discovery of non-Fibonacci spirals in such an early fossil is surprising as they are very rare in living plant species today. In fact, non-Fibonacci spirals were the most common arrangement. We took images of thin slices of fossils and then used digital reconstruction techniques to visualise the arrangement of Asteroxylon mackiei’s leaves in 3D and quantify the spirals.īased on this analysis, we discovered that leaf arrangement was highly variable in Asteroxylon mackiei. The fossils we studied are now housed in museum collections in the UK and Germany but were originally collected from the Rhynie chert – a fossil site in northern Scotland. Specifically, we studied plant fossils of the extinct clubmoss species Asteroxylon mackiei. We examined the arrangement of leaves and reproductive structures in the first group of plants known to have developed leaves, called clubmosses. Sandy Hetherington, Author provided Non-Fibonacci spirals in early plants From left to right: spirals in leaves of a monkey puzzle trees, a pine cone and in the flower of a seaside daisy. Now count the number of clockwise and anticlockwise spirals, and in almost every case the number of spirals will be integers in the Fibonacci sequence.Įxamples of living plants with Fibonacci spirals. But look closely and you can see both clockwise and anticlockwise spirals. If you pick up a pinecone and look at the base, you can see the woody scales form spirals that converge towards the point of attachment with the branch.Īt first, you may only spot spirals in one direction. These patterns are particularly widespread in plants and can even be recognised with the naked eye. In most cases, these spirals relate to the Fibonacci sequence – a set of numbers where each is the sum of the two numbers that precede it (1, 1, 2, 3, 5, 8, 13, 21 and so on). Spirals occur frequently in nature and can be seen in plant leaves, animal shells and even in the double helix of our DNA. Luisa-Marie Dickenmann/University of Edinburgh, CC BY-NC-ND What are Fibonacci spirals? Holly-Anne Turner, first author of the study, creating digital 3D models of Asteroxylon mackiei at the University of Edinburgh.

Why fibonacci sequence in nature