The Fibonacci sequence builds each number by adding the two before it — a simple rule that turns out to be everywhere in nature. When you count petals on flowers or trace spirals in sunflowers, pinecones, and pineapples, those counts often land on Fibonacci numbers. Successive leaves on flowering kale grow at about 137 to 140 degrees apart, an arrangement linked to ratios within the sequence. That angle is called the Golden Angle.

Successive leaves on flowering kale grow at about 137 to 140 degrees apart — an angle called the Golden Angle. When you measure those leaf angles and count petals that match Fibonacci numbers, the golden ratio emerges from plants you can find in any grocery store.

Successive leaves on flowering kale grow at about 137 to 140 degrees apart — an arrangement called the Golden Angle. That angle is what phyllotaxis describes: the precise pattern leaves follow as they emerge around a stem. When you measure each successive leaf on multiple plants, you can confirm the pattern holds consistently across specimens.

Shells follow a different math pattern than flowers and leaves. When you observe shell shapes in this experiment, you can trace how each whorl expands at a constant angle from the center. That consistent angle is what defines an equiangular spiral — a curve that grows wider while keeping the same angle at every turn, producing the smooth curve visible in nautilus and snail shells.