Carnivorous pitcher plant

Carnivorous plants evolved to exploit very difficult conditions. Often found in swamps and bogs where soil nutrients are scarce, carnivorous plants take much of their nourishment from the insects and small animals they trap. These plants flourish where others struggle to survive.
For vigorous growth, all plants need the same basic nutrients--including nitrogen, potassium and phosphorus. Swamps and bogs rich in decaying material like dead woody plants actually are nutrient-poor. Many essential nutrients become locked in the cycle of decomposition. In tropical highlands, the frequent rain washes most nutrients from the thin soil. Many dense rain forests also are built upon soil that is poor, with most nutrition locked away in mature living plants. All of these areas represent rich habitats to plants capable of digesting insects.