It's possible that plants that eat insects are enticing prey with distinctive fragrances.

Sarracenia pitcher plants, found in bogs throughout eastern North America, are actually modified leaves that form a cup that contains digestive enzymes. When a small animal wanders too close, the pitcher functions like a pitfall trap and digests the insect, gaining nourishment that can be difficult to get from the nutrient-poor soil in its boggy home. Different kinds of Sarracenia pitcher plants tend to eat different kinds of insects, according to different hypotheses floated by scientists. A new study, published Wednesday in the journal PLOS ONE, points to another weapon in the pitcher plants’ arsenal, which may help explain the different species’ diets: odor. Dr. Laurence Gaume, a researcher at the French National Centre for Scientific Research, or CNRS, and the University of Montpellier, has studied carnivorous plants for more than 20 years and found that the smells emanating from the different Asian pitcher plant species attracted different kinds of insects.