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the subject of the acquirement of secondary sexual characters, Mr. Darwin says: “The great eagerness of the males has thus indirectly led to their much more frequently developing secondary sexual characters.” Indeed, by all naturalists, the fact is recognized that the appearance of these characters is closely connected with the reproductive function.

      Later experiments have confirmed the observations of Mr. Darwin concerning the intelligence of the female among the lower orders of life. Among these experiments are those recently made by Professor Harper, of the Department of Biology, in the Northwestern University. Professor Harper announces that in all the experiments conducted by him, the female animal showed a greater degree of perception, or intelligence, than the male. He says: “In all my experiments, I found that the female displayed a remarkable quickness in grasping ideas which the male after numerous sluggish efforts finally accomplished.” Professor Harper declared that these facts regarding animals apply with equal force to human beings.

      Regarding the power of the female to appreciate the beauty of the males, Mr. Darwin says:

      No doubt this implies powers of discrimination and taste on the part of the female which will at first appear extremely improbable; but by the facts to be adduced hereafter, I hope to be able to show that the females actually have these powers.16

      In commenting on the fact that the female Argus pheasant appreciates the exquisite shading of the ball-and-socket ornaments, and the elegant patterns on the wing-feathers of the male, Mr. Darwin writes:

      He who thinks that the male was created as he now exists, must admit that the great plumes which prevent the wings from being used for flight, and which are displayed at courtship and at no other time, in a manner quite peculiar to this species, were given to him as ornaments. If so he must likewise admit that the female was created and endowed with the capacity for appreciating such ornaments. Every one who admits the principle of evolution, and yet feels great difficulty in believing the high taste implied by the beauty of the males, and which generally coincides with our own standard, should reflect that the nerve cells of the brain in the highest as in the lowest members of the vertebrate series are derived from those of the common progenitor of this great kingdom.

      In referring to the remarkable patterns displayed on the male Argus pheasant, designs which have been developed through Sexual Selection, Mr. Darwin says:

      Many will declare that it is utterly incredible that a female bird should be able to appreciate fine shading and exquisite patterns. It is undoubtedly a marvellous fact that she should possess this almost human degree of taste. He who thinks that he can safely gauge the discrimination and taste of the lower animals may deny that the female Argus pheasant can appreciate such refined beauty; but he will then be compelled to admit that the extraordinary attitudes assumed by the male during the act of courtship, by which the wonderful beauty of his plumage is fully displayed, are purposeless; and this is a conclusion which I, for one, will never admit.17

      Here, then, in the female bird we see developed in a remarkable degree the power of discrimination, the exercise of taste, a sense of beauty, and the ability to choose—qualities which the facts brought forward by scientists show conclusively to have been acquired by the female and by her transmitted to her offspring. Regarding males, outside the instinct for self-preservation, which, by the way, is often overshadowed by their great sexual eagerness, no distinguishing characters have been acquired and transmitted, other than those which have been the result of passion, namely, pugnacity and perseverance. This excessive eagerness which prompts them to parade their charms whenever such display is likely to aid them in the gratification of their desires is developed only in the male line.

      According to the law of heredity, those modifications of the male which have been the result of Sexual Selection appear only in the sex in which they originated. It will be well for us to remember that according to Mr. Darwin’s theory of pangenesis, sexes do not differ much in constitution before the power of reproduction is reached, but that after this time the undeveloped atoms or

      gemmules which are cast off from each varying part in the one sex would be much more likely to possess the proper affinities for uniting with the tissues of the same sex, and thus becoming developed, than with those of the opposite sex.18

      We are given to understand that secondary sexual characters are extremely variable, also that variability denotes low organization; secondary sexual characters indicate that the various organs of the structure have not become specialized for the performance of their legitimate functions. Highly specialized forms are not variable.

      To sum up the argument thus far: It has been observed that through the separation of the sexes, and the consequent division of labour, there have been established two diverging lines of development. While the male pheasant has been inheriting from his male progenitors fantastic ball-and-socket ornaments, and huge wings which are utterly useless for their legitimate purpose, the female, in the meantime, has been receiving as her inheritance only those peculiarities of structure which tend toward uninterrupted development. Within her have been stored or conserved all the gain which has been effected through Natural Selection, and as a result of greater specialization of parts, there have been developed certain peculiarities in her brain nerve-cells, by which she is enabled to exercise functions requiring a considerable degree of intelligence.

      Although this power of choice, which we are given to understand is exercised by the female throughout the various departments of the vertebrate kingdom (evidences of it having been observed among creatures even as low in the organic scale as fishes), implies a degree of intelligence far in advance of that manifested by males, it is admitted that the qualities which bespeak this superiority, namely, the power to exercise taste and discrimination, constitute a “law almost as general as the eagerness of the male.”19

      We are assured by Mr. Darwin that in the economy of nature those ornaments of the male Argus pheasant which serve no other purpose than to please the female and secure her favours, and which have been acquired at great expense of vital force, are of the “highest importance to him,” and that his success in captivating the female “has more than compensated him for his greatly impeded power of flight and his lessened capacity for running.” Yet it is plain that his compensation for this immense expenditure of vital force has not lain in the direction of higher specialization, but that while by the acquirement of these characters the processes of reproduction have doubtless been aided, the injury to the male constitution has been deep and lasting.

      Upon this subject Mr. Darwin himself says:

      The development, however, of certain structures—of the horns, for instance, in certain stags—has been carried to a wonderful extreme; and in some cases to an extreme which, as far as the general conditions of life are concerned, must be slightly injurious to the male.20

      He thinks, however, that

      Natural Selection will determine that such characters shall not be acquired by the victorious males if they would be highly injurious, either by expending too much of their vital powers or by exposing them to any great danger.

      According to Mr. Darwin, as these characters enable them to leave a more numerous progeny, their advantages are in the long run greater than those derived from more perfect adaptation to their conditions of life. It is plain, however, that this advantage, although it enables them to gratify their desires, and at the same time to perpetuate their species, does not imply higher development for the male organism.

      We have been assured by our guides in these matters that in the processes of evolution there is no continuous or unbroken chain of progress, that growth or change does not necessarily imply development, but, on the contrary, only as a structure becomes better fitted for its conditions, and only as its organs become more highly specialized for the performance of all the duties involved in its environment, may it be said to be in the line of progress. If this be true, particular attention should be directed to the fact that as secondary sexual characters do not assist their possessor in overcoming the unfavourable conditions of his environment, they are not within the line of true development, but, on the contrary, as their growth requires a great expenditure of vital force, and, as is the case among birds, they often hinder the free use of the legs in running and walking, and

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