Why my introduction of exotic species disrupt an ecosystem

If new and exotic species are introduced to an already established ecosystem, the new species might take over and become bad for the well-being of the system. The new species might not have a natural enemy, while they might eat all those bellow them in the food chain, thus disrupting it. They can also overpopulate and destroy the system in other ways.

1.wear safety goggles when heating or mixing substances 2.tie back long hair when doing experiment in order to prevent from catching fire or dipping into chemicals accidentally 3.keep all exits and passages clear4.wear laboratory coats