Fibonacci numbers and patterns in Cactus and Succulents ... 5/7

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Fibonacci in Cactus & Succulents

Mammillaria, Notocactus, Gymnocalycium, Rebutia and Ferocactus all exhibit Fibonacci sequences in their rib count or tubercule arrangement.

For example: Mammillaria lloydi has 8/13 spirals, and Mam. sempervivi has 13/21 spirals when counting in counter/clockwise directions.

Why?
Plants/cactus forms come about through evolution by laws of nature that determine the optimum shape or morphology for the conditions that they live in. So considering a plant’s shape and other biomechanical constraints or laws that determine the growth patterns and if you put this data into a computer program - the results are that the best patterns/configurations/shapes obey Fibonacci numbers in terms of rib count, rib patterns, aerole positioning etc etc. Also taken into account is energy required to form this shape. So Fibonacci numbers turn up because it is the best shape for the conditions for optimum growth or packing of cells/ribs/turbercules/aeroles with the least energy input.

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