We have already touched the topic of plant communication briefly before. While it might seem that each tree and flower is enjoying peace and solitude throughout its lifetime, it’s not entirely true. They're actually letting other plants and living creatures as far as miles away know of what's happening around by releasing specific chemicals, by transmitting electric signals, by releasing specific vibrations, by using their roots etc. The plants have actually gone as far as developing a “plant internet” that lets them communicate with each other. But the most noticeable tool of communication of plants is their movement. And we actually tend to use it for our own entertainment! Think of mimosa and you'll understand what we're talking about.
So why do some plants move when stimulated? The reasons differ from plant to plant. Some move to feed themselves, some move to escape predators, some move to preserve themselves etc. Mimosa, for example, moves for two reasons.
We have a full bush of mimosa growing in our Click & Grow HQ. Its leaves are always closed in the morning when we all get to the office. Later on, they open up, become sensitive and close up again in the evening. Turns out that when it's dark, mimosa is simply...sleeping. Scientifically, it's called nyctinastic movement or plant “sleep” in simple English.
When mimosa is “awake”, it becomes sensitive. If you touch it, shake it, blow on it or if it senses heat, its leaves close up (also called seismonastic movement). You can even create beautiful patterns by stimulating different parts of the plant or doing it in different directions! It looks fun and beautiful, but what actually happens is that the external stimuli sends an electric signal through the plant's cells, and it converts to a chemical signal that increases the cell permeability. Simply put, the stimuli creates a loss of fluid in the vacuoles of the group of cells affected, and the plant transports the water and ions to another part of the leaf, creating the closing effect. It's amazing how much is actually behind such graceful and simple movement.
Why does the mimosa do it in the first place? Apparently, its second name “Touch-me-not” is not just a trick from a reverse psychology handbook. Mimosa is actually quite a loner - by moving, it doesn't allow insect to land or stay on its leaves. But joke's on the Mimosa - even if insects are leaving it alone in the nature, we never will. It is way too much fun to have around.