Plants may compute, scientists say
New research suggests that plants might be talking to themselves.
After three years of research, two professors and two graduate students have made discoveries which indicate that the pores on the leaves of plants may be communicating with one another to solve the problems of the plant, said Jevin West, one of the graduate students who worked on the project.
West said the research could have huge implications for the study of other biological systems, as well as for computer science. West said what plants try to do is regulate the opening and closing of their pores – called stomata – in order to let the maximum amount of carbon dioxide in while letting the minimum amount of water escape.
The research has been a collaboration between West; Susanna Messinger, who is another graduate student; Keith Mott, a biology professor; and physics professor David Peak.
“What I think is beautiful about plants is the plant is bigger than a molecule and smaller than brains and they’re simpler than both,” Peak said.
It was once believed that each pore opened and closed independently, but Mott said his current belief is that each stomata communicates with its closest neighbors, eventually affecting the entire plant. Plants are similar to computers in that they compute, Mott said, but are not alike in any other way.
West said computers have a central
processing unit while plants do not. Instead of sending all input to a central place, West said, the stomata have to “talk” with one another about how much the stomata should be open.
“Now we think there’s communication going on between the stomata – that it’s not just doing it by itself – that it’s talking and communicating with its neighbors,” West said. “This communication only happens locally, so that means they’re only talking to their nearest neighbors.”
The researchers said working with plants is simple because of their size and because it is easy to control the testing environment and analyze the results of research.
“[Plants] are simpler than DNA and they’re simpler than brains and if we can demonstrate that plants … are performing computation, we will have demonstrated for the first time the reality that there is computation in living systems,” Peak said. “That, I think, is kind of cool.”
The research is done in a lab in the Biology and Natural Resources Building. The room contains machines that the researchers use to change the humidity of the air inside the chamber. They can also manipulate light, temperature and other conditions inside the small chamber which holds a few inches of the leaf, Mott said. The room also has several computers that are used to monitor the changes in the stomata.
Mott, Messinger and West have been working directly with the biology portion of the research, but Peak said he doesn’t touch the plant. Instead, he takes the data collected by the others and uses it to make a mathematical model to mimic the patterns and behavior of the patches on the leaf created by the opening and closing of the stomata, Peak said.
West said the research could have an impact not just on plants, but in the study of many other biological systems as well. Emergent computation, which is what the plant does when the stomata communicate with each other, “could be a new way in biology for studying how cells interact with one another in the absence of a neural network,” Mott said.
Although they are trying to apply the information gained about plants to other living systems, Peak said, any new information they can get about plants will be beneficial.
“Even if the only thing we do is learn better how plants work that’s pretty important. Plants feed us all. Plants are responsible for taking all of the carbon you and I are made out of out of the air,” Peak said. “Even if we only learn more about plants, that will be cool in itself.”
Mott and Peak began working on this project about three years ago when Mott noticed patches on plants he was working with. He showed his discovery to Peak, who he had known since studying as an undergraduate at Union College, where Peak had been teaching. Since then, they have been able to set up the lab where the experiments are done and they have hired graduate students and technicians to help out with the research.
“There are few places in the world where they have both the equipment and the expertise to do these experiments,” Peak said. “The students we have are great because they are not typical biology students … they both know and like computers and mathematics.”
-anihan@cc.usu.edu