Posts Tagged ‘plant intelligence’

Plants: Dumb Blondes of the Biosphere?

Tuesday, July 12th, 2011

If they think of them at all, most people see plants as domestic accessories, with all the awareness of a Marcel Breuer Wassily chair. Gardeners and other plant lovers tend to see plants as horticultural eye candy, flaunting their pretty flower heads solely for our pleasure. Until very recently, even most scientists assumed that plants are essentially passive—rooted in place, taking whatever moisture, nutrients, and sunlight chance brings their way. It’s not exactly surprising, then, that the word “vegetable” is used to describe people with brain damage so severe they have no discernable awareness.

A trove of new research, however, is demonstrating that plants are far from botanical automatons. To be sure, researchers have found no signs of Socratic logic or Shakespearean poetry in the plant kingdom. But there is so much new data on plant intelligence—including abilities like sensing and, yes, even learning, remembering, and recognizing kin—that the investigation of plant intelligence is suddenly a serious scientific endeavor.

The latest case in point: You know the perennial debate over the role of nature vs. nurture—heredity or the environment—in the development of a human being? Studies have shown that, depending on their distinct personal experiences, identical human twins can have a different chance of getting a disease. Well, it turns out that in this respect plants may not be so different from people.

In a new study, University of Toronto biologists found that genetically identical poplar trees—clones—responded to drought differently, depending on the nursery the plants were obtained from. They took cuttings of the poplar clones from nurseries in two different regions of Canada and regrew them under identical climate-controlled conditions. Half of the trees were then subjected to drought. Since the trees were regrown under identical conditions, the researchers predicted all the specimens would respond to drought in the same manner, regardless of where they had come from. But low and behold, the genetically identical specimens responded differently to the drought treatment, depending on their place of origin.

Malcolm Campbell, one of the study’s authors, called the finding “quite stunning.” “A tree’s previous personal experience influences how it responds to the environment,” he said. In other words, the trees “remember” where they came from.

Discoveries such as this have the potential to transform the public’s view of plants. In fact, they’re helping to transform our understanding of the nature of intelligence itself.

They also have practical implications for gardeners, landscape designers, and foresters: The “memory” of previous experience discovered in this study could help determine how plants from a particular nursery will respond to conditions in a particular landscape. It may also help predict how certain plants will respond to climate change or other environmental stresses.

Plants: Dumb or Brainy?

Tuesday, July 1st, 2008

It’s time to ditch, once and for all, the notion that plants are the dumb blondes of the biosphere. The typical suburban or city dweller sees plants as domestic accessories, with all the awareness of an Eames molded plywood chair. Even plant lovers tend to see them as horticultural eye candy, flaunting their pretty flower heads solely for our pleasure.

Set aside for a moment the fact that plants are capable of converting sunlight into food, or that some canny orchids can produce blooms that look so much like female bees that they’re magnets for the lovesick males who unintentionally pollinate the plants while attempting to copulate with their flowers. To me, this has always been evidence that plants are really smart.

Now scientists have demonstrated that some species can recognize members of their own family. In the British journal Biology Letters, plant ecologist Susan A. Dudley and colleague Amanda File set off a bit of a ruckus in the rarefied world of plant biology by describing an experiment in which they planted the Great Lakes sea rocket, Cakile edentula var. lacustris, in pots. Turns out there was a lot less competition when siblings shared the same container than when groups of strangers grew in a common pot — a feat of altruism members of our own species are not always capable of pulling off.

In fact, there’s so much new data on plant intelligence, including abilities like sensing and, yes, even learning and remembering, that scientists are now arguing about whether plants can be said to have nervous systems, if not brains. A scientific group called the Society for Plant Neurobiology was recently established to provide a venue for biologists interested in exploring, in their words, “complex plant behavior.” This prompted a backlash by three dozen exasperated scientists who published an article, “Plant Neurobioloogy: No Brain, No Gain?”, that took members of the new society to task for discussing the possibility that plants have neurons, synapses, and some vegetable equivalent of a brain, long considered the province of animals exclusively. Eric D. Brenner of The New York Botanical Garden, along with four other scientists, countered, “No one proposes that we literally look for a walnut-shaped little brain in the root or shoot tip.” But, they insisted, we should be open to the possibility that plants have their own sort of nervous system.

To keep abreast of the latest on plants as intelligent life forms, see the Society for Plant Neurobiology’s peer-reviewed journal, Plant Signaling & Behavior.