Sunflowers use a cross-pollination method of reproduction by attracting animals and insects such as bees and using them to spread reproductive pollen from one flower to another. Sunflowers can self-reproduce, but by doing this, they don't have the diverse offspring that are better suited to their environment.
When sunflowers have fully flowered, their anthers produce a sweet pollen mixture that attracts bees. The anthers are the outer area of the stamen, which is the flower's male sexual organ. The bees then use the nectar to create honey. When the bees drink the nectar, the pollen sticks to the bee's feet.
As the bee moves between different sunflowers to drink their nectar, the pollen on their legs comes into contact with the stigma, a sticky outer end of the flower's female reproductive organ known as the pistil. Once the pollen is forced into the stigma, it releases sperm, which fertilizes an egg within the pistil. This egg is then buried below ground, and a new flower is formed. Sunflowers are fast reproducers, and seeds can germinate between five and 10 days below ground.
Alternatively, a sunflower can self-reproduce by twisting itself around its own pollen. However, this method only produces an identical flower, and not one that has the benefits of the best genes from the other flowers around it. This produces sunflowers that are capable of conditions that change over periods of time.