Aloe polyphylla, the famous spiral

The twisting pattern in the leaf rosette of the spiral aloe or Aloe polyphylla is special, due to the larger number of leaves found here than in other Aloe species that display the phenomenon. Five dense spiral arrays of leaves emanate from the centre as the plant grows. The arrangement may spiral clockwise or anticlockwise.

The pattern is neat and regular enough to inculcate a love of geometry in some observers. Fibonacci number sequences come to mind. They provide fitting descriptions of many such phenomena in the biological domain, although the spirals in this case do not match Fibonacci numbers, but adhere to the pattern of a different mathematical series. Regular leaf patterns can sometimes be matched with the pattern in some or other numerical series. Similar spirals are found in certain shell and seed shapes. Another example of such a series, Lucas Numbers, also describes some of the regular patterns found in nature. Patterns consistent with Fibonacci series are the most common though. Much fun can be had from exploring number series like Fibonacci’s Golden Ratio (about 1.618034), by which consecutive numbers increase in the series. Go Google!

Whether one becomes fascinated by the numbers or not, biological examples like this leaf rosette hold their beauty in the simple regularity, their magic in the regularity of acceleration (Frandsen, 2017; Van Wyk and Smith, 2003; iNaturalist; Wikipedia; www.maths.surrey.ac.uk).