Biology helpers!? PLEASE HELP me!? with this problem.?

Question

Jest one question. Please. =|

1.) Why do introduced species often cause secondary succession?

Answer 1

Lily

I'm not sure about this, I'm afraid. It seems that introducing a non-native species to an area would upset the existing ecological balance, and might lead to significant change in the plant and animal composition of the area. If that change (and the killing off of existing plants or animals) was sufficiently large, then secondary succession would take place, with replacement plants colonising the area to fill the resulting gaps.

Tom