Ever wondered why they call it a “Secret” garden? The reason stretches far beyond the mystery of their location. Plants all around us have been acting like humans and remain unsuspecting to the vast majority of us! Of what has been revealed from the dedicated research, there is still complex plant behaviour that just cannot be explained. Despite this, the advantages that certain behaviours bring to plants and their similarities with those of humans, may present opportunities to justify some of our own behaviours, be they good or bad.
According to Plants it’s ok to…
…Talk to Yourself, as Long as there are Plants Around
It’s no secret that plants possess an extraordinary ability to communicate with each other. In fact the green thumbs of the world, including his Royal Highness, the Prince of Wales, have even cultivated the art of conversing with plants themselves. Research has suggested that certain types of sound wave may possibly interfere with the normal activity of some plant genes. Comparing sound exposure and the lack of it to pea plants revealed that the stimulus of sound might actually lead to greater plant mass. While certainly not conclusive just yet, this phenomenon remits the attention of keen gardeners and much more research from botanists.
…Fake an Illness
The “Elephant Ear” plant, which can be found in the everyday garden, mimics being ill to discourage mining moths from eating its otherwise healthy leaves. The process is known as Variegation and is commonly caused when plants lose their green chlorophyll cells, making them appear white. Naturally a plant lacking chlorophyll cells would have its ability to photosynthesise restricted and appear weak. Feigning this sickness detracts insect pests from eating plants and can strengthen their long-term success. So if it’s photo day at school and an acne outburst leaves you resembling a variegated leaf, pulling a “sickie” might be an effective course of action.
A leaf damaged by mining moths (left) compared to one faking it (right)
Image source: BBC
Plants are very selective when it comes to choosing mates. They have a self-incompatibility system that helps them reject unwanted pollen. Often this is to avoid accepting the pollen of other species that can result in infertile off-spring or in some cases to avoid being fertilised by their own pollen. The tomato, tobacco, and egg plants have been subjected to the bulk of this research. While the reasons for the incompatibility system are understood, the understanding of it at a molecular level isn’t. The mechanisms behind recognising wanted and unwanted pollen still remains a mystery. As humans, it seems we can take comfort in the fact that although our reasons for disqualifying someone as a potential mate may appear irrational and inexplicable, it just might serve us well in the long run!
Mimosa Pudica, also known as the “touch-me-not” plant, is very shy to physical contact. In fact the slightest prod or gentle shake can cause it to close its leaves, and remain closed for up to half an hour! Its leaf cells react to pressure and transfer water to their adjacent cells. Cells with reduced water levels lose their strength in their cell wall causing the leaf to close. It is thought that this shy behaviour is used to surprise pests with their rapid change and scare them off. It just goes to show, sometimes being shy means being safe.
…Reach For the Sky!
If only metaphorically, this is another trait that humans and plants share in common. Plants grow up towards the sun to fuel their ever important process of photosynthesis. The plant hormone, auxin, promotes plant growth. It accumulates on the plant cells that are in the absence of light. Therefore the shaded side of a plant tends to grow faster than the side in the sunlight, causing the plant to grow towards the sun. Their leaves which reach out to the sun can now photosynthesis and are rewarded with precious glucose, in contrast to fame and riches which humans may be rewarded with from reaching for the sky!
The personification of plant behaviour doesn’t stop there either. There are plants that exist which have been known to cry out for help with chemicals, change their appearance to attract pollinators and even establish a neighbourhood watch!