How much thought have you given to these curvy plant structures?
Since the nineteenth century, the curves of these specialized vine structures have caught the attention of botanists. Some, like Charles Darwin, were puzzled by the technique many vines use to cling to their surroundings and to hoist themselves in search for sunlight. Darwin’s book published in 1865, On the Movements and Habits of Climbing Plants, is one of the earliest and most comprehensive studies of tendrils.
Tendrils are used by climbing plants for: support, attachment, climbing, and cellular invasion (by parasitic plants) by twining around suitable hosts. They are specialized stems, leaves, or petioles with a thread-like shape.
Grape vine tendrils grow opposite a leaf at the node.
When first formed, a tendril is almost straight, and while growing, it slowly waves around in a poorly understood process called circumnutation. When it encounters a foothold, the end of the tendril wraps around it, securing support.
Tendrils are thigmotropic, which means that they are sensitive to touch. When they come in contact with a support, growth on that part of the tendril accelerates, forming the coil. Tendrils take on spring shapes and hold the vine tightly to the support. In fact, these coils can absorb energy, and are very helpful for the vine in strong winds.
In 2012, a group of Harvard University scientists investigated the nature of tendrils coiling up into corkscrew-like helices- one right-hand coil the other a left-hand coil. Their discoveries reveal the mechanism and plant-structure composition that allow coils to twist without causing the plant to twist at the other end. Want to learn about the magic of how curves in plant structure make this possible? Click this link and watch a fascinating video: Scientists unwind the secrets of climbing plants’ tendrils
Science behind this post: (some facts in this post have been cut and pasted from these sites)
Weekly Photo Challenge: “Curves“