Turns out humans didn’t invent the silent disco: a new study from Tel Aviv University (TAU) and the University of Colorado Boulder (CU Boulder) has revealed that the original group behind the idea of quietly dancing together is tall, strong and full of chlorophyll.
According to the universities’ research published in Physical Review X, sunflowers optimize their growth in cramped conditions by “dancing”: using a combination of random movements and responses to neighboring plants’ shadows to maximize their collective exposure to sunlight.
TAU’s Prof. Yasmine Meroz, who led the study with CU Boulder’s Prof. Orit Peleg, explained that sunflowers grown in dense environments exhibit a zigzag growth pattern, because it allows them to grow side by side without overshadowing each other, ultimately maximizing photosynthesis for the entire group.
“In fact,” she added, “plants know how to distinguish between the shadow of a building and the green shadow of a leaf. If they sense the shadow of a building, they usually don’t change their growth direction, because they ‘know’ that will have no effect. But if they sense the shadow of a plant, they will grow in a direction away from the shadow.”
The researchers used time-lapse photography to observe sunflowers grown in high-density conditions. They discovered that individual plants engaged in what they described as a “dance,” making random movements ranging from tiny shifts to displacements of up to two centimeters every few minutes (this is very similar to my own style of dancing, which I have coined as “the static anxious groove”).
These movements, known as circumnutations, were first observed by the famous bald master of evolution, Charles Darwin. However, their functional role has remained a mystery until now.
Through computer simulations and statistical analysis, the team demonstrated that these random movements, combined with the plants’ ability to detect and respond to neighboring shadows, allow sunflowers to find optimal growth directions collectively.
“The sunflower plant takes advantage of the fact that it can use both small and slow steps as well as large and fast ones to find the optimum arrangement for the collective,” Meroz noted.
“This is somewhat like a crowded dance party, where individuals dance around to get more space: if they move too much they will interfere with the other dancers, but if they move too little the crowding problem will not be solved, as it will be very crowded in one corner of the square and empty on the other side. Sunflowers show a similar communication dynamic – a combination of response to the shade of neighboring plants, along with random movements regardless of external stimuli,” she elaborated.
This discovery doesn’t just solve a long-standing scientific puzzle; it also provides insights into plant behavior and collective problem-solving in nature — and it serves as a lesson to oblivious silent disco dancers to fan out and utilize the entire dance floor so that we’ve all got a little space to breathe, David.
Produced in association with ISRAEL21c
