Pitcher plants are carnivorous plants that have modified leaves known as pitfall traps for capturing prey like insects and rodents. However, some species have started shifting their diets to animal waste. Now, scientists know why.
Because of the nutrient-poor environment they live in, pitcher plants have evolved modified leaves filled with fluids to lure insects, arachnids, and sometimes rodents. These fluids also help in digesting the bodies of the trapped prey and extract important nutrients, such as nitrogen and carbon.
Just less than a decade ago, scientists discovered that a handful of Nepenthes pitcher plant species have evolved from consuming insects to mammal waste. These pitcher plants still lure animals, such as birds and mammals, to feed on their nectar, but instead of trapping them, the plants allow them to feed, then defecate into the pitcher-shaped leaves.
According to new research, the said species of pitcher plants have evolved to consume animal waste because of their much higher nutritional value compared to insects. It is also noted that more often, these species live in high-altitude places where fewer insects thrive, hence the need to have alternative sources of nitrogen and other nutrients to survive.
The case of animal waste-eating pitcher plants shows the direct relationship between ecology and evolution.