Monica Gagliano, an evolutionary ecologist at the University of Western Australia, thought her experiment on associative learning in plants wasn’t working. Her team was trying to find out whether you could train common peas in a way similar to how Pavlov trained his dogs. But the two-week experiment was over, with no results — or so she believed.
“I went into the lab to dismantle everything. And then I suddenly realized that these plants were doing what I was looking for — and doing it so well, so beyond my expectations, that I couldn’t even see it at first,” she says.
For the first time, Gagliano and her colleagues showed that you can train plants the same basic way you can train dogs. While Pavlov’s mutts learned that the ring of a bell meant food was coming, Gagliano’s team taught the garden peas to associate a fan with light.
The researchers placed seedlings under a maze made out of plumbing pipes; the growing pea had to make a choice each time it hit a fork in the road whether to go left or right.
The first three days were devoted to training. Gagliano taught one group of peas that if a fan blew at them from a certain part of the maze, a blue light (something all peas crave) would follow. Another group of seedlings was trained that when the fan blew, the light would appear in the opposite corridor. For the third group, acting as a control, there was no association between the fan and the light.
