Many cultures have stories of talking trees that give advice as well as warnings to people. Alexander the Great and Marco Polo were said to have visited such a tree in India. And in some modern stories, such as the film Avatar, trees can communicate with animals and people. With our long believing that talking plants are unreal, new research has found something amazing: It turns out that plants can really communicate.
It has been known that plants use chemicals to communicate with each other. This happens when a plant, say a bean plant, gets attacked by insects. The plant gives off chemicals from the leaves that are being eaten. This is like a warning, or a call for help, "I'm being attacked!" When another bean plant feels the chemicals from its poor neighbor, it starts to give off its own, different chemicals. Some of these chemicals drive insects away. Others attract insects—the wasps! The wasps kill the insects that are eating the bean plant. Scientists hope to learn more about this plant warning system, so that we can use it to grow crops without pesticides (杀虫剂).
More surprisingly, plants also use sounds to communicate. People can't hear these sounds, but plants are making them. Some plants make noises with their roots. Corn and chili plants do this. They also "listen" to the noises from other plants. A chili plant can tell if a neighboring plant is helpful, or unfriendly. Some trees make clicking noises when there is not enough water.
Most surprisingly of all, plants have an amazing system of communication that can link nearly every plant in a forest. Scientists call this system "wood wide web". It is in some ways like the Internet we use. This wood wide web is linked underground by fungi (真菌). Using this wood wide web, plants can share information and even food with each other. But just like our Internet, this wood wide web has its own version of "cybercrime (网络犯罪)". Plants can steal food from each other, or spread something harmful to attack other plants.
Scientists are learning more every day about the secret ways in which plants talk to each other. Maybe we will know enough about plant communication to be able to "talk" with them ourselves in the near future. Let's wait and see.
