A species
Sunflower
Helianthus annuus
Hundreds of tiny flowers in one sunny head
You and the sunflower last shared an ancestor about 1.8 billion years ago (on 28 July, if life's history were one year).
What looks like one huge sunflower is really hundreds of tiny flowers packed onto a head often about as wide as your hand. The ring, usually bright yellow, is made of petal-like flowers that make no seeds. The dark middle holds hundreds of tiny tubes arranged in crisscrossing spirals. A bee moving around on top can reach hundreds of them in one visit.
This tall plant may surprise you. It is a distant cousin of lettuce, as well as daisies and chicory, in the daisy family. It grows in sunny open places like meadows, farm fields and roadsides.
Young growing heads follow the sun from east to west each day and turn back east overnight, guided by the plant's inner clock. Once full grown, heads stop following the sun and stay facing east. The morning sun warms them early. Warm east-facing heads attract about five times as many pollinating insects in the morning as heads facing west.
A one-summer life
Each plant sprouts, flowers, makes seeds and dies in a single warm season. Wild plants bloom for about six weeks in mid to late summer.
Makes room for itself
The plants leak natural chemicals into the soil that hold back other plants growing nearby. This helps them grow in thick groups.
Seeds that are really fruits
The striped 'seeds' people snack on are really dry fruits, each with one true seed inside. These fruits and the leaves feed birds, squirrels and insects.