As stated by Huffington Post
Basically, plants in the study were able to “hear” themselves being eaten, creating a type of defense mode against their prey, the caterpillar.
Using a laser microphone, the scientist were able to record the vibrations and sounds of caterpillars chewing on plant leaves. The scientists played them to the plants before caterpillars had a chance to nibble. As it turns out, when plants were exposed to these chewing vibrations for a few hours, they reacted by producing increased amounts of mustard oils — which caterpillars hate!
So technically they can hear themselves being eaten alive!
Many articles are springing up with “bad news for vegan community” based on this finding, but researchers only said that this finding will help find new ways to defend plants against pesky insects.