There are few things as pleasurable as a vase of flowers in the house or the scent of freshly cut grass. However, your life-long appreciation of these small pleasures is about to be ruined by the revelation that plants might actually experience pain when damaged.
As it turns out, the scent given off by cut grass is actually a chemical distress mechanism used to signal nearby animals to intervene and save it when being attacked. Otherwise defenseless, plants use a variety of molecular responses to protect themselves, including emitting chemicals to poison attackers or attract helpful insects in the area. These reactions, ingrained in the plants on a biological level, constitute a kind of communication. Does this mean that plant life could actually also feel pain the way sentient beings do?
Research conducted at the Institute for Applied Physics at the Germany’s University of Bonn, found that plants release gases that are effectively a cry of pain. Scientists have even identified sound waves emitted by injured plants alongside the aforementioned gases. Far from restricted to one type of plant, among the many species of plants that emit the survival-instinct sounds (inaudible to the human ear) are cucumbers and many flowers.
Apparently, plants can even hear themselves being eaten. Researchers at the University of Missouri found that plants can register and respond to chewing sounds made by caterpillars that eat them.
Some researchers believe that the existence of these “emergency” signaling systems prove that plants can sense pain. Others argue that without a brain or nervous system, there are no feelings to be felt.
We have all witnessed plants, as they grow, moving toward light or altering their trajectories because of disruptions. These adaptations occur because of a complex biological network distributed throughout a plant’s roots, leaves, and stems. Previous research has already shown that even trees in a 30 meter square forest can “communicate,” sending each other certain biological signals in the case of an attack, or need for assistance with nutrition.