Another theory is that man probably originated in some continent of the Arctic Circle, where, as we know from fossil remains of the Miocene and Eocene periods, Greenland and Spitzbergen enjoyed a mild climate and forest vegetation, admirably adapted for the evolution of a temperate mammalian fauna, including the human species. This is a very plausible theory, but at present it is a mere theory, like that of a lost Atlantis, or submerged continents in the Pacific or Indian Oceans. The only thing approaching to evidence to support it is, as far as I am aware, that Sir Joseph Hooker and other eminent botanists think that the diffusion of the forest trees and other flora of America can be traced along lines radiating from the extreme north, along the mountain chains and elevated plateaux which form the backbone of the continent from Alaska to Tierra del Fuego. There seems a probability also that the evolution of the human race, which turns mainly on the development of the erect stature, which is the basis of the larger brain and other anatomical differences between man and the other quadrumana, must have taken place not in tropical regions of dense forests, where climbing would have had a decided advantage over walking in the struggle for life, but rather in some region of wide plains and open forests, where it would be an advantage to see enemies or prey at a distance, or over tall grass or ferns. It must be admitted, however, that in our present state of knowledge all these theories of the place, time, and manner of human origins are speculations rather than science. We have proof positive that man was already spread over most parts of the world in the Quaternary period, and the irresistible inference that he must have existed long before, is confirmed by conclusive evidence as to the finding of his remains and implements in the earliest Quaternary and latest Pliocene periods, and very strong evidence for carrying them back into the Miocene. Anthropoid apes, which are so similar to man in physical structure, and in their ways are as highly specialized from any more general and primitive ancestral form as man himself, undoubtedly did exist in the Miocene period, and have come down to us with comparatively little change. It puzzles the best anatomists to find any clear distinction between the present Hylobates and the Hylobates of the Middle Miocene, while that between the white man and the Negro is clear and unmistakable. Why then should "Homo" not have existed as soon as "Hylobates," and why should any prepossession in favour of man's recent creation, based mainly on exploded beliefs in the scientific value of the myths and guesses of the earliest civilized nations of Asia, stand in the way of accepting the enormous and rapidly increasing accumulation of evidence, tracing back the evolution of the mammal man to the same course of development as other mammals?