Can plants feel pain? Not really, but they can sense a lot more than you might give them credit for!
That's right, plants talk to each other. And we're just starting to understand them.
Dr. Appel took this research one step further when she discovered "listening plants."
In the study, caterpillars were placed on Arabidopsis, a small flowering plant related to cabbage and mustard. Using a laser and a tiny piece of reflective material on the leaf of the plant, Cocroft was able to measure the movement of the leaf in response to the chewing caterpillar.
Cocroft and Appel then played back recordings of caterpillar feeding vibrations to one set of plants, but played back only silence to the other set of plants. When caterpillars later fed on both sets of plants, the researchers found that the plants previously exposed to feeding vibrations produced more mustard oils, a chemical that is unappealing to many caterpillars.
Here's a video that shows the instruments that Dr. Appel and her collaborator, Dr. Rex Cocroft, used in their experiment.
There's so much to learn about "listening" plants. Like, how do they hear? That's what Dr. Appel is working on now. (Psst... do you think the plants in her photo are listening to her?)
There's lots more information and research about the field of plant communication. Here's a start:
Quanta Magazine: The Secret Language of Plants
Mental Floss: 5 Ways Plants Communicate
BBC Earth: Plants Communicate Using the Internet of Fungus
What a Plant Knows, by Daniel Chamovitz
What questions do you have after learning about plant senses? How do you think scientists would answer them? Let us know at firstname.lastname@example.org!
Post-note: Did you know that Stevie Wonder created an entire album inspired by plants? It's called Journey Through the Secret Life of Plants. It was based on a book called "The Secret Life of Plants" and the album provided the score to a documentary. Unfortunately, the book and the documentary are based on faulty science, and set back real research on plant communication. But the album is still.... interesting... to hear. Turn it on next time you're gardening!