Did you know that plants can communicate between themselves, with insects and even (in a very limited fashion) humans?
Researchers have found that plants pass signals through chemicals, "listen" to vibrations and even send electrical signals. Let's look at...
Researchers have found that plants pass signals through chemicals, "listen" to vibrations and even send electrical signals. Let's look at...
- Say It With Chemicals: How plants communicate with compounds
- Good Vibrations: How plants respond to sound
- Electric Tomatoes: How plants transmit signals through the roots and fungi
- Personal Space: How plants react to being touched
- Social Networking: How trees keep in touch
- Plant to Human Communication: Has science figured out a way to talk to plants?
 |
| Plants can "hear" caterpillars eating... (Sara Codair) |
Say It With Chemicals
Plants don't have mouths with which to speak, but that hasn't stopped them communicating with other vegetation... or even some animals. Rather than using sound, they can "talk" by releasing chemicals into the atmosphere and the rhizosphere - the soil around their root systems.
So what would a plant want to say? It's possible that they could pass on information about hungry animals or pest infestations, attract useful creatures or even ward off competing plants. Research suggests that a damaged plant can release "volatile organic compounds" that act like a distress signal and tell other plants to produce defensive toxins. They can even attract carnivorous creatures that might scare off or kill whatever is attacking the plant!
So what would a plant want to say? It's possible that they could pass on information about hungry animals or pest infestations, attract useful creatures or even ward off competing plants. Research suggests that a damaged plant can release "volatile organic compounds" that act like a distress signal and tell other plants to produce defensive toxins. They can even attract carnivorous creatures that might scare off or kill whatever is attacking the plant!
 |
| Meaning other plants can prepare for attack! (Portia Weiss) |
Good Vibrations
Though people occasionally claim that plants speak to them, plants simply don't have the vocal equipment to make conversation. That doesn't mean that plants can't "hear" (or at least detect patterns in) vibrations though.
In a rather strange experiment, researchers recorded the sounds of a caterpillar eating leaves and played the audio back to other plants. These serenaded plants actually responded by preparing a variety of nasty chemical defenses - and when caterpillars were placed on these prepared plants, they faced stronger concentrations of toxins than when feeding on unprepared plants.
Perhaps the most interesting thing the researchers found was that the plants could tell the difference between the sounds of caterpillars chomping and other "safe" noises - including leafhopper mating calls and the sound of the wind. Neither of these triggered the same defensive response!
In a rather strange experiment, researchers recorded the sounds of a caterpillar eating leaves and played the audio back to other plants. These serenaded plants actually responded by preparing a variety of nasty chemical defenses - and when caterpillars were placed on these prepared plants, they faced stronger concentrations of toxins than when feeding on unprepared plants.
Perhaps the most interesting thing the researchers found was that the plants could tell the difference between the sounds of caterpillars chomping and other "safe" noises - including leafhopper mating calls and the sound of the wind. Neither of these triggered the same defensive response!
 |
| Researchers found that tomatoes produce electric signals... (Dani California) |
Electric Tomatoes
If the idea of plants "listening in" on vibrations isn't weird enough for you, how about plants sending electrical signals through the ground?
Researchers have discovered tomato plants sending small electrical signals through the surrounding mycorrhizal network - or in simpler terms, the mesh of roots and fungi found in most soil. It's not unique to these plants either - similar transmissions were found in aloe vera and cabbage plants. What we don't know is what information plants can pass along in this fashion - though the idea of plants using fungi and roots as an impromptu telephone is pretty funny!
Researchers have discovered tomato plants sending small electrical signals through the surrounding mycorrhizal network - or in simpler terms, the mesh of roots and fungi found in most soil. It's not unique to these plants either - similar transmissions were found in aloe vera and cabbage plants. What we don't know is what information plants can pass along in this fashion - though the idea of plants using fungi and roots as an impromptu telephone is pretty funny!
 |
| The sensitive plant folds its leaves in response to being touched... (Wallace Fonseca) |
Personal Space
Did you know that plants can sense when they are being (or are about to be) crowded?
You may have heard of things like sensitive plant whose leaves respond to contact by closing up and drooping. Scientists have found that quite a few plants actually use physical contact as a way to determine the presence of rival vegetation!
Researchers found that mouse-ear cress leaves would attempt to "reach for the sky" after contacting the leaf tips of other plants. Other researchers found that potato plants would add branches and grow leaves higher up their stems after being "brushed."
This actually makes sense - being near rivals means that a plant will need to grow above the competition if it wants good access to light!
You may have heard of things like sensitive plant whose leaves respond to contact by closing up and drooping. Scientists have found that quite a few plants actually use physical contact as a way to determine the presence of rival vegetation!
Researchers found that mouse-ear cress leaves would attempt to "reach for the sky" after contacting the leaf tips of other plants. Other researchers found that potato plants would add branches and grow leaves higher up their stems after being "brushed."
This actually makes sense - being near rivals means that a plant will need to grow above the competition if it wants good access to light!
.jpg) |
| Researchers have found trees communicate through fungi and their roots! (Sebastian Unrau) |
Social Networking
Generally people think of fungus as being a parasite that feeds on trees - the reality is much more complicated. While there certainly are parasitic fungi out there, mycorrhizal fungi live in a mutualistic relationship with plants. They attach to root systems and siphon off a portion of the sugars produced by plant photosynthesis... but in return, the plant draws off some of the nutrients the fungus has harvested from the soil.
Researchers have found that these mycorrhizal networks go well beyond a single plant. In fact, these meshes of biomatter can link local vegetation together and be used for plant-to-plant communication. Perhaps the strangest finding so far has been that trees can "donate" resources to their nutrient or light-starved kin through the network!
Researchers have found that these mycorrhizal networks go well beyond a single plant. In fact, these meshes of biomatter can link local vegetation together and be used for plant-to-plant communication. Perhaps the strangest finding so far has been that trees can "donate" resources to their nutrient or light-starved kin through the network!
 |
| Scientists have found a way to spy on (and activate) Venus flytraps... (Andi Superkern) |
Plant to Human Communication
Do you remember how I said that we can't talk to plants? Scientists are currently trying to change that... and to some extent, they've succeeded.
Researchers were able to fix an electrode to a Venus flytrap plant (not an easy task, given their rough and waxy surface) which allowed them to do two things: a) pick up electrical signals from the plant as it responded to the environment and b) open and shut the traps. They were even able to use the plant as a grabber, like a robotic hand.
So that's a neat trick, but what would being able to communicate with plants actually do for us? For one thing, we could eavesdrop on growing crops and get warned when they are being infested with pests. We could even signal them to prepare chemical defenses ahead of time, saving us the trouble of spraying them down with costly (and environmentally harmful) pesticides!
Thanks for reading - you might also be interested in...
Researchers were able to fix an electrode to a Venus flytrap plant (not an easy task, given their rough and waxy surface) which allowed them to do two things: a) pick up electrical signals from the plant as it responded to the environment and b) open and shut the traps. They were even able to use the plant as a grabber, like a robotic hand.
So that's a neat trick, but what would being able to communicate with plants actually do for us? For one thing, we could eavesdrop on growing crops and get warned when they are being infested with pests. We could even signal them to prepare chemical defenses ahead of time, saving us the trouble of spraying them down with costly (and environmentally harmful) pesticides!
Thanks for reading - you might also be interested in...