Abigail Ticker in Smithsonian Magazine:
Venus flytraps’ considerable eccentricities have confined them to a 100-mile-long sliver of habitat: the wet pine savannas of northern South Carolina and southern North Carolina. They grow only on the edges of Carolina bays and in a few other coastal wetland ecosystems where sandy, nutrient-poor soil abruptly changes from wet to dry and there’s plenty of sunlight. Fewer than 150,000 plants live in the wild in roughly 100 known sites, according to the North Carolina Department of Environment and Natural Resources.
Instead of absorbing nitrogen and other nutrients through their roots, as most plants do, the 630 or so species of carnivorous plants consume insects and, in the case of certain Southeast Asian pitcher plants of toilet-bowl-like proportions, bigger animals such as frogs, lizards and “the very, very occasional rodent,” says Barry Rice, a carnivorous plant researcher affiliated with the University of California at Davis. The carnivores are particularly abundant in Malaysia and Australia, but they’ve also colonized every state in this country: the Pine Barrens of coastal New Jersey are a hot spot, along with several pockets in the Southeast. Most varieties catch their prey with primitive devices like pitfalls and sticky surfaces. Only two—the Venus flytrap and the European waterwheel, Aldrovanda vesiculosa—have snap traps with hinged leaves that snag insects. They evolved from simpler carnivorous plants about 65 million years ago; the snap mechanism enables them to catch larger prey relative to their body size. The fossil record suggests their ancestors were much more widespread, especially in Europe.