How Do Sunflowers Chase The Sun?
One of the most fascinating flowers on Earth that trace the movement of a star so systematically is the sunflower. If you have ever been in a sunflower field on a sunny morning, you would experience pure joy as the flowers warm up to the Sun and follow its path.
We all know that the sunflowers are following the Sun in the direction it goes. In a study published, research has revealed that the sunflower’s internal clock and the ability to detect light work together turning on genes related to growth at just the right time to bend with the arc of the Sun. A 24-hour circadian rhythm guides them. The research team also showed that when fully grown as tall as people in some cases plants that always face East get a head start warming up early to attract pollinators.
So, do the flowers follow the sun or the plant does it before even flowering?
The American plant biologist, Winslow R. Briggs, who studied the plant’s behavior, says he had observed the plant even before the flowering starts exhibits a behavior called the ‘sun-tracking’. Briggs was an international leader in molecular biological research on how plants respond to light for growth and development and for understanding blue-light photoreceptor systems. The elongating vegetative stems mimic the behavior and follow the east to west movement following the sun.
According to Winslow, the plant might have had adopted this mechanism for a specific reason. Did the light-induced solar tracking develop to help the plant be the tallest in the field, opening up to invite the pollinators or are the flowers might have been tracking the sun to warm themselves?
Did you know the movement of the plant while tracking the Sun is made by water gain or loss – Osmosis?
There is a special organ called pulvinus, which is at the base of the leaf petioles that functions as the osmotic motor.
To test the theory of the Sun warming up the flower, the scientist tried to replicate the heat to match that of the Sun. But the pollination was much less in the artificially heated samples indicating that the Sun’s heat was faster and probably more welcoming. While being ready for pollination is a major factor, it might just be one of the reasons why the plant tracks the Sun. But millions of sunflowers around the world, dutifully track the Sun from East to West every day and droop down in the night only to reorient themselves in the morning, ready to chase the Sun again.
Who taught the plant to do that?
Isn’t nature awesome?