All "Nepenthes" are passive carnivores with no moving parts, unlike their distant cousins the Venus flytrap. "Nepenthes rafflesiana" kills by luring its prey into its pitchers, whose peristomes secrete a sweet-tasting nectar. Once the insect is inside, it quickly finds the walls of the pitcher too slippery to scale and drowns. Digestive enzymes released by the plant into the liquid break down the prey and release soluble nutrients, which are absorbed by the plant through the walls of the pitcher. The carnivorous nature of "Nepenthes" is supposedly a consequence of living in nutrient-poor soils; since the main method of nutrient absorption in most plants (the root) is insufficient in these soils, the plants have evolved other ways to gain nutrients. As a result, the roots of "Nepenthes" and most other carnivorous plants are slight and fragile; hence care must be taken when repotting. All "Nepenthes" are dioecious, meaning that each individual plant has only male or female characteristics.