ANTIQUITY OF MAN ON EARTH, AND HIS FIRST HOME.
Having established the probability that man is of only one zoological species, we may next proceed to inquire when and where he first appeared on earth. Not that it necessarily follows that he appeared at one place only. The unity of a species does not require this. Whatever Power brought it into being at one place might have also acted with the same result in several. Naturalists do not insist that all the members of a species shall be descended from one pair of ancestors. Were it to happen that some inventive resident of another planet should devise an aerial car and pay us a visit, and we should find that he was in all respects like one of ourselves, we should unhesitatingly claim him as of the same species, although there could be no talk of commnnity of ancestry.
Relation of Man to Other consideration renders the question of the whereabouts of man's first appearance somewhat more involved. On the other hand, it is greatly lightened by the acknow ledged fact that in the advent of organic forms on earth it is a uniform law that they bear fixed relations to the forms around them. Their existence, indeed, is conditioned by the presence of a number of similar forms anterior to them. Hence we need only look for the first abode of man in some locality which was peopled at the time by the highest mam mals, those placed next to him in the zoological scale ; that is, the man like apes. The climatic conditions which best suited their life were also such as were most favorable to him in the infancy of the race.
But this inquiry carries us far afield, for we cannot confine ourselves to the physical geography of the globe as it now is, but must look at it at the period when the earliest signs of man's occupancy present them selves.
Here Geology must be asked to the assistance of Ethnology, for the time is past when we can suppose that the period of the existence of man can be measured by a few thousand years. Evidence that cannot be con troverted proves that tens of thousands of years ago he, or some creature possessing faculties like him, roamed widely over the face of the earth, then under climatic conditions strangely dissimilar from those with which modern geography is familiar.
A very brief sketch of the doctrines of Geology may make this branch of our subject more easily comprehended. Students of that science divide the rocky strata which make up the earth's crust into Primary, Secondary, and Tertiary strata, the Primary being the oldest, the Ter tiary the most recent. Some, indeed, consider the Tertiary as reaching down to and including the present age, but most are of accord in calling this latter by a different term. By these the Tertiary age or epoch is subdivided into three minor ages—the Eocene, which is the oldest ; the Miocene ; and the Pliocene, which is the latest. After this is placed by some the Pleistocene, by others the Quaternary, epoch—terms often used as almost synonymous to designate the period intervening between the close of the Tertiary and the beginning of the Geologic age in which we live, this being known as the Alluvial or Actual age.
Climate.—The climate of the world differed exceedingly in these vari ous epochs. Thus in the Miocene and early Pliocene, Greenland enjoyed as mild and as balmy a climate as the Madeira Islands or Southern Florida does to-day. Tropical animals, as the rhinoceros, the elephant, and numerous apes and monkeys, found a congenial home where now the raw climate of the British Isles will not admit of the ripening of Indian corn.
Glacial Epoch.—But at or near the close of the Tertiary period a tre mendous change took place, the most extraordinary known in the geologic annals of the world. The genial warmth disappeared, and in place of it vast sheets of ice descended from the polar continents of both the Arctic and Antarctic regions, and covered the greater part of the land to the thirty-fifth or fortieth parallel with a solid sheet of snow and ice to a depth of thousands of feet. The continental areas of the globe were greatly changed ; a land-bridge which had connected North America with Northern Europe was wholly torn away ; the ragged edges of Norway and the coast of Maine remain as proofs of the mighty power of the ice-mass, while the Great Lakes and Prairies of Central North America and the Pampas of South America are so many witnesses to its effect on existing land-areas.