Alien species invasion leads to extinction of indigenous species' - Justify this statement by considering two animals as examples.

Explanation

Ex.1. The Nile perch introduced into LakeVictoria in east Africa lead to the extinction of more than 200 species of cichlid fish in the lake.
Ex.2. The invasive weed species like carrot grass (Parthenium). Water hyasinth (Eicchornia) and Lantana posed threat to our native species.
Ex.3. The illegal intorduction of African cat fish (Clarias gariepinus) posed threat to indigenous cat fishes in our rivers.