My interest in biogeography is documented by papers I wrote from my PhD thesis on… which was on biogeography; it was on the spread of the serin finch across Europe, right up to a major book which is right now in press, dealing with the birds of northern Melanesia. In 1974, I published a collection of essays called Evolution and the Diversity of Life and in this volume are reprinted nine of my major papers dealing with the field of biogeography, and I’ll deal… I will explain some of the subjects with which I dealt. For instance, it is always claimed that the… establishment of plate tectonics in the mid-1960s completely changed everything in biogeography. By contrast, I showed that as far as birds are concerned, plate tectonics required only one single change in our interpretations and that has to do with a connection across the north Atlantic from North America across Greenland to Norway and northern England. All other aspects… all other connections that plate tectonics established are irrelevant as far as birds are concerned because they deal with much earlier periods.