ANATOMY OF BIRDS
GEOGRAPHICAL DISTRIBUTION
MIGRATIONS OF BIRDS
CLASSIFICATION OF BIRDS
LIZARD-TAILED BIRD
AMERICAN TOOTHED-BIRDS
THE OSTRICHES
THE RHEAS
EMEUS AND CASSOWARIES
THE TINAMOUS
THE KIWIS
THE PENGUINS
LOONS AND GREBES
ALBATROSSES & PETRELS
STORK-LIKE BIRDS
GOOSE-LIKE BIRDS
FALCON-LIKE BIRDS
FOWL-LIKE BIRDS
CRANE-LIKE BIRDS
PLOVER-LIKE BIRDS
CUCKOO-LIKE BIRDS
THE ROLLER-LIKE BIRDS
SPARROW-LIKE BIRDS
Birds and Birding's Guide to:
Watching GEOGRAPHICAL DISTRIBUTION OF BIRDS
The distribution of life over the globe is known as biogeography. With that branch of the subject dealing with the distribution of animals (zoogeography) we are of course at present only concerned with the distribution of birds. Although earlier attempts had been made to correlate certain observed facts of avian distribution, it was not until about the middle of the last century that the subject was placed on a logical and scientific basis. These earlier attempts failed because it was undertaken to delimit life areas by degrees of latitude and longitude, or by the lines of political division, while in the light of present understanding it needs but a moment's reflection to disclose the fact that the distribution of life on the earth must depend upon natural causes and conditions, and only occasionally and quite by accident to coincide with the political divisions.
Inasmuch as most birds possess the power of flight, which enables them to pass easily and quickly from one area to another, or, within certain limitations, even from one hemisphere to another, it might be inferred that their distribution would be relatively uniform, but such is far from being the case. If a person reasonably familiar with the bird life of eastern North America should journey around the world, first crossing this continent, and thence by way of Central America through South America, and by way of Polynesia to New Zealand, Australia, Asia, Europe, and Africa, he could not fail to be impressed with the marked differences in the birds coming under notice. In a few cases, such as afforded by the pelagic and far-wandering Albatrosses, Petrels, Gulls, Terns, and Tropic-birds, he might find the same species at several widely separated points in the journey; in many instances he would note the presence of familiar groups, — as Ducks, Woodpeckers, Kingfishers, Hawks, Owls, — but in the vast majority of cases the species would be entirely different, while in not a few, whole families and orders would appear and disappear in succession.
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