在一项新的研究中, physicists from the United States 和 Israel may have gotten to the bottom of a quirky behavior of growing plants—和 a mystery that intrigued Charles 达尔文 himself during the later decades of his life.

For many humans, plants might seem stationary 和 even a little dull. 但是绿色的东西会移动很多. If you watch a timelapse video of a sunflower seedling poking up from the soil, 例如, 它不是直接向上射出的. 而不是, 随着向日葵的生长, 它的王冠绕着圆圈旋转, 拧成开瓶器和, 在一般情况下, 四处摆动——尽管非常缓慢.

现在, researchers co-led by Orit Peleg at CU Boulder 和 Yasmine Meroz at Tel Aviv University have discovered one role for these chaotic movements, 也被称为“绕行”.“在温室实验和计算机模拟中, the group showed that sunflowers take advantage of circumnutations to search the environment around them for patches of sunlight. 

“A lot of people don't really consider the motion of plants because, 作为人类, we're usually looking at plants at the wrong frame rate,法勒说, a co-author of the study 和 an associate professor in the BioFrontiers研究所 和 计算机科学系.

这个团队 8月发表了研究结果. 15 发表在《博彩app推荐》杂志上.

The findings could one day help farmers to come up with new strategies for growing an array of crops in more efficient arrangements.

“Our team does a lot of work on social interactions in insect swarms 和 other groups of animals,Chantal Nguyen说, lead author 和 a postdoctoral researcher at BioFrontiers. “But this research is particularly exciting because we’re seeing similar dynamics in plants. 他们扎根于地面.”

达尔文的黄瓜

Nguyen added that plants don’t usually shift around like animals but, 而不是, 随着时间的推移，朝着不同的方向成长. This phenomenon enchanted 达尔文 long after he returned from his voyage on the HMS Beagle, 根据历史记载.

19世纪60年代, 达尔文, who was then suffering from a range of ailments that limited his own mobility, 花了几天时间在家里观察植物. 他种植了黄瓜和其他物种的种子, then traced how their crowns moved around from day to day—the resulting maps look wild 和 haphazard.

“I am getting very much amused by my tendrils—it is just the sort of niggling work 哪一个 suits me,” he 1863年一位朋友写道.

Amused or not, 达尔文 couldn’t explain why some of his tendrils twisted.

It’s a mystery that has also perplexed Meroz, a physicist by training. 2017年的一项研究 给她指出了正确的方向. 在这, scientists led by the University of Buenos Aires grew lines of sunflowers under cramped conditions. They discovered that the plants naturally 和 consistently arranged themselves into a zig-zag pattern, 就像拉链的牙齿一样. The arrangement likely helps the plants maximize their access to sunlight as a group.

Meroz wondered if plant wiggles could be the engine that drives such patterns in plant growth.

"对于攀缘植物, it’s obvious that it’s about searching for supports to twine on,梅洛兹说, 植物科学和食品安全教授. "But for other plants, it’s not clear why it’s worth it.”

太阳出来了

To find out, she 和 her colleagues grew five, one-week-old sunflowers in rows. Then, like 达尔文 before them, they mapped out how the plants moved over the course of a week. 

下一个, Nguyen 和 Peleg developed a computer program to analyze the patterns behind the sunflower growth. The researchers could also use their computer simulations to see what would happen if the sunflowers moved more or less—in other words, if they wiggled haphazardly or in a slow 和 steady pattern. 

如果数字植物完全不摆动, 研究小组发现, they would all wind up all leaning away from each other in a straight line. If they wiggled too much, in contrast, they would grow in a r和om pattern. 如果它们的移动具有适当的随机性, 然而, 向日葵呈锯齿状排列, 哪一个, 现实生活中的植物, 提供了大量的阳光. Nguyen explained that plants seem to circumnutate to find where the best light is coming from, 然后朝着那个方向成长.

“当你在系统中添加一点噪音时, it allows the plant to explore its surroundings 和 settle into those configurations that allow each plant to find maximum light exposure,”她说。. “That happens to lead to this nice zig-zag pattern that we see.”

在未来的实验中, the researchers will test out how sunflowers grow in more complicated arrangements. Meroz, 对她来说, is glad to see plants get some credit for the movers 和 shakers they really are.

“如果博彩平台推荐都和植物生活在同一个时间尺度上, 你可以走在街上，看到他们在移动,”她说。. “也许博彩平台推荐都会养植物当宠物."