A novel ecosystem is a new type of ecosystem that is created when an unusual combination of plants, animals, and other living things are brought together in a single place. It can happen naturally, when different plants and animals move into the same area, or it can happen when people create an artificial environment, like a zoo. Novel ecosystems often happen when species that weren't meant to be together find themselves living in the same place. For example, two different kinds of trees might be planted in the same forest, and they might start to mix together, changing the whole makeup of the ecosystem. Novel ecosystems can also happen when animals that weren't meant to be together, like different kinds of fish, start to live in the same lake. A novel ecosystem can create a really interesting mix of plants and animals, but it can also have negative effects on the environment.