"If the signal has been received by network members, then the damage is very much reduced compared to the control where the signal was not received," Stuefer said.
He and his colleagues first put forward the theory of communicating plants in 2004. Recent papers published in the journal Oecologia present the data on network communication.
André Kessler is an assistant professor of ecology and evolutionary biology at Cornell University in Ithaca, New York. He said this sort of signaling makes sense for networks of genetically identical plants, such as those that grow using runners.
"If one plant out of the clone is attacked, the probability that a second [connected] clone will be attacked in the future is very high," he said.
"So there must be a strong selection on actually giving the signal to the neighboring clone, because you increase your fitness that way."
The protective measures have their drawbacks, so "crying wolf" can have severe costs, study leader Stuefer pointed out.
The defensive changes, for example, limit the growth and development of the plants.
His team also found that plants allocate less energy and biomass to their root system when they are busy repelling caterpillars.
"If a plant is stressed by below-ground factors like drought or lack of nutrients, that can easily become a cost," Stuefer said.
The networks are also vulnerable to viruses, which spread through the interconnected plants with the same ease that virtual viruses multiply in a computer network, according to Stuefer.
"We don't know how much damage these viruses do, but I think that's the main drawback from having such a network," he said.
"But the fact [that the network is] there and I think it's common in these plants—this suggests the benefits over the long term are bigger than the costs."
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