Why are invasive species dangerous to the environment?

Invasive species do not have natural predators and therefore usually overgrow, invading other species habitat and breaking the normal ecosystem process.

Explanation:

When a species its brought by human mistake to a new environment where they can successfully adapt and grow. This invasive species can usually reproduce and grow rapidly, using many resources and therefore affecting the native species.  Part of their success its because in many cases, they do not have natural predators or pests. A well known example its the introduction of the Lionfish to the Caribbean Sea.  

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