Phyllotaxis

In botany, phyllotaxis or phyllotaxy is the arrangement of leaves on a plant stem (from Ancient Greek phýllon 'leaf' and táxis 'arrangement'). Phyllotactic spirals form a distinctive class of patterns in nature. In botany, phyllotaxis or phyllotaxy is the arrangement of leaves on a plant stem (from Ancient Greek phýllon 'leaf' and táxis 'arrangement'). Phyllotactic spirals form a distinctive class of patterns in nature. The term was coined by Charles Bonnet to describe the arrangement of leaves on a plant. The basic arrangements of leaves on a stem are opposite and alternate (also known as spiral). Leaves may also be whorled if several leaves arise, or appear to arise, from the same level (at the same node) on a stem. With an opposite leaf arrangement, two leaves arise from the stem at the same level (at the same node), on opposite sides of the stem. An opposite leaf pair can be thought of as a whorl of two leaves.