Not all ecologists spend their days in the presence of nature’s majesty, contemplating redwood groves or mountain lakes or rain forest canopies. Since 1988, Stephen Heard has been peering into a gruesome little roadside attraction called the purple pitcher plant. This bog dweller is actually quite charming to look at--it has a nodding brick-red bell of a flower and purple-veined leaves that curve in on themselves to form scalloped pitchers--but what Heard is interested in are the plant’s feeding habits. The Venus flytrap screams, ‘I’m eating insects!’ says Heard, a Canadian ecologist now at the University of Iowa. The pitcher plant does not. But if you look closely, you can see that inside the leaf are hairs that all point down. Once you, as an insect, start wandering down, it’s hard to turn around. Below those hairs is a slick, slippery band, and when you step onto that--whish, you slide down.
The sweet smell of nectar had attracted you as an insect, but instead of drinking that nectar you end up plummeting into the pool of rainwater at the bottom of the pitcher. The rainwater is not pure: the plant secretes chemicals into it that cause the water to coat your body like oil, and it pumps out protons until the water is as acidic as vinegar. Before long you drown. Then you become food for the pitcher plant.
