Plants Can Hear Themselves Being Eaten


Bad news for vegetarians and salad connoisseurs today; apparently plants can ‘hear’ themselves being eaten.

A new study, seemingly taken right from the screenplay of Sausage Party, has found that plants can identify sounds in their environment and react accordingly with defence mechanisms.

Researchers at the University of Missouri discovered that plants, upon hearing the crunch of a caterpillar devouring their leaves, release mustard oils, which are unappealing to caterpillars and ward them off, reports the New Zealand Herald.


Heidi Appel of the Bond Life Sciences Center at MU:

Previous research has investigated how plants respond to acoustic energy, including music. However, our work is the first example of how plants respond to an ecologically relevant vibration.

We found that ‘feeding vibrations’ signal changes in the plant cells’ metabolism, creating more defensive chemicals that can repel attacks from caterpillars.

Appel, senior research scientist in the Division of Plant Sciences in the College of Agriculture, Food and Natural Resources collaborated with Rex Cocroft, professor in the Division of Biological Sciences at MU.

Their study saw Arabidopsis, a small flowering plant related to cabbage and mustard, subjected to the chewing of a caterpillar. Cocroft used tiny lasers to measure the plant’s movement response.

The researchers proceeded to play recordings of caterpillar feeding vibrations to one set of plants, and only silence to another set of plants.


When caterpillars later fed on both sets of plants, those previously exposed to feeding vibrations produced more mustard oils, a defensive chemical to ward off caterpillars, than the other test group of plants.

Cocroft concluded:

What is remarkable is that the plants exposed to different vibrations, including those made by a gentle wind or different insect sounds that share some acoustic features with caterpillar feeding vibrations did not increase their chemical defences.

This indicates that the plants are able to distinguish feeding vibrations from other common sources of environmental vibration.


The study, funded in part by the National Science Foundation was published in Oecologia, and the results could be applied to agricultural sectors.

The initial study shows that plants – while they do not have consciousness – may have the potential to elicit their own defence mechanisms from certain pests and crop killers when certain vibrations are omitted.

The next step for Appel and Croft’s research is to determine how, and why, vibrations are sensed by plants. They also want to know what types of attributes of the complex vibrational signal are integral and how these mechanical vibrations communicate with other plants to activate a defensive response to hostile insects.


Cocroft says:

Plants have many ways to detect insect attack, but feeding vibrations are likely the fastest way for distant parts of the plant to perceive the attack and begin to increase their defenses.

Appel added that:

Plants have many ways to detect insect attack, but feeding vibrations are likely the fastest way for distant parts of the plant to perceive the attack and begin to increase their defenses.

Caterpillars react to this chemical defense by crawling away, so using vibrations to enhance plant defenses could be useful to agriculture,’ Appel said.

‘This research also opens the window of plant behavior a little wider, showing that plants have many of the same responses to outside influences that animals do, even though the responses look different.


In light of this new information it will be interesting to see the vegetarian, and perhaps more interestingly the vegan community’s response to these new claims.

Will it force them to rethink their diet and eating habits once more, or will they continue to eat plants regardless of the possible implication that they are physically hurting sentient beings who are aware and have pain receptors?

That being said, there are a host of other considerations vegetarians can justifiably still appeal to.