Q.Give examples of extinctions caused by the invasion of alien species.

[!TLDR] Introduced alien species have driven native species to extinction, e.g. the Nile perch in Lake Victoria. …

[!ANSWER] Alien (non-native) species introductions have caused well-documented extinctions of native species.

When a species is introduced, deliberately or accidentally, into an ecosystem where it did not evolve, the native species there often have no evolved defences against it — whether it acts as a predator, a competitor, or a carrier of new disease. The clearest textbook example is the introduction of the Nile perch, a large predatory fish, into Lake Victoria in East Africa: the Nile perch preyed heavily on the lake's hundreds of native cichlid fish species, many of which were found nowhere else, and this single introduction is credited with driving a large number of these endemic cichlid species to extinction or to the edge of extinction within just a few decades. …

• Giving only a generic answer ("invasive species cause extinction") without a specific named example. …