Updated

Updated · KSL.com · Jun 11

Scientists Find Venus Flytrap Snaps by 30%-40% Cell-Wall Softening, Not Water Shifts

Updated

Updated · KSL.com · Jun 11

Scientists Find Venus Flytrap Snaps by 30%-40% Cell-Wall Softening, Not Water Shifts

Q: If plants lack muscles, what does the flytrap's instant snap reveal about their hidden ability to move?

The Venus flytrap’s snap shows that plants can produce extremely fast, precise movement without muscles by rapidly changing the mechanical properties of their cells. The new research indicates that when an insect bends the trap’s trigger hairs, the plant sends an electrical signal that quickly softens cells on the outer surface of the leaf. That softening releases stored elastic energy in the curved trap, causing it to flip shut in about a second, much like a rubber popper toy snapping inside out. Researchers found the cell walls can relax by roughly 30 to 40 percent, making this one of the fastest mechanical changes ever measured in plant tissue. That matters because it overturns older ideas that the trap mainly closed through water shifting inside the leaf. Using dental glue to hold traps partly open and a nanoindenter to measure stiffness, the team showed the key change was not water loss or deflation, but a rapid increase in cell-wall flexibility. More broadly, the finding reveals that plants have a sophisticated hidden motion system based on mechanosensing, electrical signaling and tunable cell mechanics. In other words, plants do not need muscles to move quickly: they can sense touch, alter their tissues almost instantly, and convert stored internal stress into action. The Venus flytrap is an extreme example of a wider plant ability to detect and respond to the physical world with far more speed and control than once assumed.

3 articles · Updated · KSL.com · Jun 11

High-speed tests and mechanical measurements showed the Venus flytrap closes when the outer epidermal cell walls rapidly soften by about 30%-40%, releasing stored stress and triggering snap-buckling.
The finding overturns a hypothesis that had stood for more than a century, after researchers also measured water transport in the trap tissue and ruled out fluid redistribution as the driver.
One-tenth of a second is enough for the trap to shut after an insect touches its trigger hairs twice, while the softening itself develops in roughly one second in the preloaded leaf.
Published in Science, the work settles a question dating back to Darwin and suggests a biological design principle that could eventually inform soft robots and smart materials.