Work Step by Step
Dispersal can happen very quickly if there is a niche to exploit. Take, for example, the brown tree snake in Guam. It was introduced there at some point in the 1940's, and since then has decimated the population of local birds. Many species endemic to Guam are now extinct in the wild. The landscape of the forests of the island has been completely changed, with other species exploiting the lack of bird predation.