Robert Langdon (1995:77) disputes the long-standing proposition that Rattus exulans was dispersed by Polynesian voyaging and suggests that over hundreds of thousands or millions of years it "succeeded in getting from one island to another without any human aid at all." Between this and the conventional view lies the possibility, not yet explored in detail, that some rats were transported on canoes that had lost their human crew. I discuss this is relation to New Zealand, but the principles are the same for Easter Island.</p