As elementary school students, we all learn that leaves contain a pigment called chlorophyll, which colors leaves green. And shortly after, we middle-school scientists usually discover that through a process called photosynthesis, plants can use chlorophyll and energy from the sun to turn carbon dioxide, water and minerals into food.

So it took me by surprise when a recent nature center visitor asked me if plants can eat anything else. “Are there,” he asked me earnestly, “other ways for plants to feed themselves?”

Perhaps surprisingly, the answer is: yes.

On our planet, there is a diverse type of plants that have evolved a very different strategy than the one we learn about as children. These plants, alien as it may seem, can actually eat animals.