It was just like an invasion in a science fiction movie.

It's likely that such lags reflect, at least in part, adaptive changes in the invader to suit it to the new environment.

We find that toads with longer legs can not only move faster and are the first to arrive in new areas, but also that those at the front have longer legs than toads in older populations.

We don't know what effect it may have to remove so many top predators from a complex tropical ecosystem, but it's likely to be bad news.