A friend recently sent me a link to an excellent article by Michael Pollan published in The New Yorker magazine, entitled “ The Intelligent Plant”. It’s a great overview of what science knows to date about the behaviours and awareness of plants. (Check it out here.)
I found the work of Monica Gagliano particularly intriguing. She is an animal ecologist who designed an ingenious experiment to determine to what extent plants are capable of the most basic form of learning: habituation. Gagliano used mimosa pudica, the sensitive plant, so-called because of its tendency to fold up its leaves in response to being touched, shaken, or dropped. She designed an apparatus that would drop each potted plant a distance of 15 centimeters every 5 seconds for a total of 60 drops per “training” session.
Of the 56 plants in the experiment, all of them eventually disregarded the dropping experience, leaving their leaves open once they determined it to be a “safe” experience. Several of the plants began leaving their leaves open after as few as 4, 5, or 6 drops. When these plants were later shaken by researchers, they all folded their leaves in response. They easily distinguished between being dropped and being shaken. In addition, when returned to the dropping experiment after a 28 day vacation, the plants remembered their previous experiences and left their leaves open. They had learned about being dropped.
The nascent science of plant neurobiology (a controversial term for many scientists as plants have no neurons or brain) is demonstrating that plants are fully capable of learning and remembering. They communicate information to each other through chemical and possibly other forms of signalling. They recognize kin. They form networks of mutual support sharing water and food. They have a minimum of 15 distinct senses through which they perceive their environment, using these to perform such amazing feats as sending their roots around rocks and toxic materials before they have even touched them.
Plants are more akin to animals than most scientists are ready to admit. Though many in the scientific community find the words “plant intelligence” to be offensive or unsettling, I find it reassuring. After all, we rely on the plant kingdom for oxygen, food, water purification, soil stabilization, soil creation, primary chemical research, and a host of other services. Clearly, they know what they are doing. Clearly, they have our backs.