Question

Why do invasive species often become pests?

Answer 1

Because the environment is not used to them, causing an imbalance.

Explanation:

Invasive species are species that were introduced into an environment that is very different from their original, sometime intentionally, and sometimes not. The living things there have not adapted to the species. Of course, the species has to survive, so they eat, build homes, and do their thing. However, this usually upsets the balance because the organisms haven't adapted.

A very good example is the emerald ash borer. This small beetle, which is native to northeastern Asia, is believed to have arrived on a Chinese ship bearing wood packing materials. The beetle started wreaking havoc, destroying ash trees everywhere. In the beetle's native countries, the trees have developed a resistance to the ash borer. The ash trees here haven't, so it was very destructive.