times, before they reached their present homes. (64. Latham, Man and
his Migrations, 1851, p. 135.) The early progenitors of man must also
have tended, like all other animals, to have increased beyond their
means of subsistence; they must, therefore, occasionally have been
exposed to a struggle for existence, and consequently to the rigid law
of natural selection. Beneficial variations of all kinds will thus,
either occasionally or habitually, have been preserved and injurious
ones eliminated. I do not refer to strongly-marked deviations of
structure, which occur only at long intervals of time, but to mere
individual differences. We know, for instance, that the muscles of our
hands and feet, which determine our powers of movement, are liable,
like those of the lower animals, (65. Messrs. Murie and Mivart in their
Anatomy of the Lemuroidea ( Transact. Zoolog. Soc. vol. vii. 1869,
pp. 96-98) say, some muscles are so irregular in their distribution
that they cannot be well classed in any of the above groups. These
muscles differ even on the opposite sides of the same individual.) to
incessant variability. If then the progenitors of man inhabiting any
district, especially one undergoing some change in its conditions, were
divided into two equal bodies, the one half which included all the
individuals best adapted by their powers of movement for gaining
subsistence, or for defending themselves, would on an average survive
in greater numbers, and procreate more offspring than the other and
less well endowed half.
Man in the rudest state in which he now exists is the most dominant
animal that has ever appeared on this earth. He has spread more widely
than any other highly organised form: and all others have yielded
before him. He manifestly owes this immense superiority to his
intellectual faculties, to his social habits, which lead him to aid and
defend his fellows, and to his corporeal structure. The supreme
importance of these characters has been proved by the final arbitrament
of the battle for life. Through his powers of intellect, articulate
language has been evolved; and on this his wonderful advancement has
mainly depended. As Mr. Chauncey Wright remarks (66. Limits of Natural
Selection, North American Review, Oct. 1870, p. 295.): a
psychological analysis of the faculty of language shews, that even the
smallest proficiency in it might require more brain power than the
greatest proficiency in any other direction. He has invented and is
able to use various weapons, tools, traps, etc., with which he defends
himself, kills or catches prey, and otherwise obtains food. He has made
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