Alfred Russel Wallace

“ We cannot expect the regions to be so well defined in the case of plants as in that of animals; and there are sure to be many anomalies and discrepancies, which will require long study to unravel. The Six Great Regions here adopted, are however, as a whole, very well characterised by their vegetable forms. The floras of tropical America, of Australia, of South Africa, and of Indo-Malaya, stand out with as much individuality as do the faunas; while the plants of the Palæarctic and Nearctic regions, exhibit resemblances and diversities, of a character not unlike those found among the animals. ”

“ Having now closed our survey of the animal life of the whole earth—a survey which has necessarily been encumbered with a multiplicity of detail—we proceed to summarize the general conclusions at which we have arrived, with regard to the past history and mutual relations of the great regions into which we have divided the land surface of the globe. ”

“ The early North American flora, on the other hand, seems to have been essentially the same in type as that which now exists there, and which, in the Miocene period, was well represented in Europe; and it is such as now flourishes best in the warmer parts of the United States. But whatever conclusion we may arrive at on the question of climate, there can be no doubt as to the distinctness of the floras of the ancient Nearctic and Palæarctic regions ”

“ The two temperate regions have thus come to resemble each other more than they once did, while the Oriental retains more of the zoological aspect of the great northern regions of Miocene times. The Ethiopian, from having been once an insular region, where lower types of vertebrates alone prevailed, has been so overrun with higher types from the old Palæarctic and Oriental lands that it now rivals, or even surpasses, the Oriental region in its representation of the ancient fauna of the great northern continent. ”

“ In going back through the long series of the Tertiary formations, in Europe, Asia, and North America, we find a continuous succession of vertebrate forms, including all the highest types now existing or that have existed on the earth. ”

“ The fact, however, is that the fauna of each has been derived, independently, and perhaps at very different times, from the north, with which they therefore have a true genetic relation; while any intercommunion between themselves has been comparatively recent and superficial, and has in no way modified the great features of animal life in each. ”

“ In the Southern Hemisphere there appear to have been three considerable and very ancient land masses, varying in extent from time to time, but always keeping distinct from each other, and represented, more or less completely, by Australia, South Africa, and South America of our time. ”

“ All the palæontological, no less than the geological and physical evidence, at present available, points to the great land masses of the Northern Hemisphere as being of immense antiquity, and as the area in which the higher forms of life were developed. ”

“ The Neotropical region has probably undergone great fluctuations in early times; but it was, undoubtedly, for long periods completely isolated, and then developed the Edentate type of Mammals and the Formicaroid type of Passerine birds into a variety of forms, comparable with the diversified Marsupials of Australia, and typical Passeres of the Eastern Hemisphere. ”

“ But we believe they will apply equally to elucidate the phenomena presented by the distribution of all terrestrial organisms, when combined with a careful consideration of the various means of dispersal of the different groups, and the comparative longevity of their species and genera. Even insects, which are perhaps of all animals the farthest removed from mammalia in this respect, agree, in the great outlines of their distribution, with the vertebrate orders. The Regions are admittedly the same, or nearly the same for both ”