Description

A few thousand years ago thisIsland was nothing notable, justbare rock and sand. The ancestors ofplants and animals that we now considernormal scenery, our present crops,pests, diseases and peoples, all had towend their weary ways, by accident ordesign, to their new home. Since thetime-scale is so short, priority of arrivalshould be of no great consequence toanybody except the historian — particularlysince population change andmovement are biological norms.However, sometimes a species maysucceed in arriving well in advance ofits natural competitors and enemies.With this head start and a good climateit may outstrip its predators,evade diseases and parasites, thrive ina more congenial home.