Pop Culture
Jun 11, 2009, 12:06PM

Testing their limits

Plants, that is. Understanding botanical behavior.

In a somewhat different world, Consuelo M. De Moraes would be revolutionizing vampire fiction.Her lab at Penn State University studies predators that entangle prey in a tight embrace, pierce victims’ tissue and suck out nourishment. In the last few years, De Moraes and her colleagues have found that the predators even hunt down prey by scent.Creepy as her predator, Cuscuta pentagona, is, it is also, frankly, a plant. Better known as five-angled dodder, its orange tentacles bypass the porcelain throats of young women in favor of the slim stems of young tomato plants. De Moraes and other researchers are showing that plants behave and misbehave as dramatically as animals. But there’s still not much hope for a feature-length dodder movie.“I think most people regard plants as being pretty unresponsive and stuck in one place,” laments ecologist Richard Karban of the University of California, Davis. “Now, animals, they’re interesting because they can change and act in response to their environment.”It’s a dichotomy Karban doesn’t accept for one second. When he and an animal behaviorist recently supervised a grad student, he remembers, “I would constantly want to say, ‘Oh yeah! Yeah! Plants do that too!’” Recent findings on plant capacities, he declares in a 2008 paper in Ecology Letters, reveal “high levels of sophistication previously thought to be within the sole domain of animal behavior.”Even plants less vampirish than Cuscuta vines forage strategically for their food, and there’s evidence that plants fight each other over resources. In a broad sense of the word, plants communicate — some essentially scream for help. Also, a plant can respond to stimuli depending on its history of previous experiences, a tendency Karban is willing to call a sign of memory.Karban stops there, but other plant scientists go much further in borrowing animal terminology. In May, researchers gathered in Florence, Italy, for their fifth annual meeting on “plant neurobiology,” and some of these green neuroscientists talk about searching for a plant “brain.” The June issue of Plant, Cell & Environment, devoted to plant behavior, even begins with a paper that uses the term “plant intelligence.”Expanding the language for describing plants to include at least some “behavior” words could expand ideas for research, Karban contends. Plant researchers might do well to borrow analytic techniques from animal scientists, he adds. Finally, everyone may discover just how exciting it can be to watch grass grow.


Register or Login to leave a comment