Herbert Spencer

“ When we have thousands of men whose profit or loss depends on the truth of their inferences from perpetually-repeated observations; and when we find that their inferences, handed down from generation to generation, have generated an unshakable conviction; we may accept it without hesitation. In breeders of animals we have such a class, led by such experiences, and entertaining such a conviction—the conviction that minor peculiarities of organization are inherited as well as major peculiarities. ”

“ The many sorts of dogs which, if we accept the physiological test, we must consider as all of one species, show us in a marked manner the hereditary transmission of small differences—each sort, when kept pure, reproducing itself not only in size, form, colour, and quality of hair, but also in disposition and speciality of intelligence. ”

“ Besides seeing the Negroes continue to produce Negroes, copper-coloured men to produce men of a copper colour, and the fair-skinned races to perpetuate their fair skins—besides seeing that the broad-faced and flat-nosed Calmuck begets children with broad faces and flat noses, while the Jew bequeaths to his offspring the features which have so long characterized Jews; we see that those small unlikenesses which distinguish more nearly-allied varieties of men, are maintained from generation to generation. ”

“ Such facts compel us to admit that the components of an organism have a proclivity towards a special structure—that the adult organism when mutilated exhibits that same proclivity which is exhibited by the young organism in the course of its normal development. ”

“ For if an organism A, has, by any peculiar habit or condition of life, been modified into the form A′, it follows that all the functions of A′, reproductive function included, must be in some degree different from the functions of A. An organism being a combination of rhythmically-acting parts in moving equilibrium, the action and structure of any one part cannot be altered without causing alterations of action and structure in all the rest ”

“ Visceral modifications of a normal kind are observable but obscurely, or not at all. And if the changes of structure worked in individuals by changes in their habits are thus difficult to trace, still more difficult to trace must be the transmission of them: further hidden, as this is, by the influences of other individuals who are often otherwise modified by other habits. Moreover, such specialities of structure as are due to specialities of function, are usually entangled with specialities of structure which are, or may be, due to selection, natural or artificial. ”

“ In most cases it is impossible to say that a structural peculiarity which seems to have arisen in offspring from a functional peculiarity in a parent, is wholly independent of some congenital peculiarity of structure in the parent, whence this functional peculiarity arose. We are restricted to cases with which natural or artificial selection can have had nothing to do, and such cases are difficult to find. ”

“ And here the assumption to which we seem driven by the ensemble of the evidence, is, that sperm-cells and germ-cells are essentially nothing more than vehicles in which are contained small groups of the physiological units in a fit state for obeying their proclivity towards the structural arrangement of the species they belong to. ”

“ Equally marked is the case of the immigrant Germans who, though they keep very much apart, rapidly assume the prevailing type. To say that "spontaneous variation" increased by natural selection, can have produced this effect, is going too far. Peoples so numerous cannot have been supplanted in the course of two or three generations by varieties springing from them. Hence the implication is that physical and social conditions have wrought modifications of function and structure, which offspring have inherited and increased. ”

“ Some of the best illustrations of functional heredity, are furnished by mental characteristics. Certain powers which mankind have gained in the course of civilization cannot, I think, be accounted for without admitting the inheritance of acquired modifications. The musical faculty is one of these. To say that "natural selection" has developed it by preserving the most musically endowed, seems an inadequate explanation. Even now that the development and prevalence of the faculty have made music an occupation by which the most musical can get sustenance and bring up families ”

“ Rather than admit that the eyes of these creatures living in darkness have disappeared from lack of use, some contend that such creatures would be liable to have their eyes injured by collisions with objects, and that therefore natural selection would favour those individuals in which the eyes had somewhat diminished and were least liable to injury: the implication being that the immunity from the inflammations due to injuries would be so important a factor in life as to cause survival. ”

“ And if the organism A, when changed to A′, must be changed in all its functions; then the offspring of A′ cannot be the same as they would have been had it retained the form A. That the change in the offspring must, other things equal, be in the same direction as the change in the parent, appears implied by the fact that the change propagated throughout the parental system is a change towards a new state of equilibrium—a change tending to bring the actions of all organs, reproductive included, into harmony with these new actions. ”

“ A species of plant that has been transferred from one soil or climate to another, frequently undergoes what botanists call "change of habit"—a change which, without affecting its specific characters, is yet conspicuous. In its new locality the species is distinguished by leaves that are much larger or much smaller, or differently shaped, or more fleshy ”

“ These slightly-different units severally multiply at the expense of the nutriment supplied to the unfolding germ—each kind moulding this nutriment into units of its own type. Throughout the process of development the two kinds of units, mainly agreeing in their proclivities and in the form which they tend to build themselves into, but having minor differences, work in unison to produce an organism of the species from which they were derived, but work in antagonism to produce copies of their respective parent-organisms. ”

“ Not a single domestic animal can be named which has not in some country drooping ears; and the view suggested by some authors, that the drooping is due to the disuse of the muscles of the ear, from the animals not being much alarmed by danger, seems probable." Again—"The eyes of moles and of some burrowing rodents are rudimentary in size, and in some cases are quite covered up by skin and fur. This state of the eyes is probably due to gradual reduction from disuse, but aided perhaps by natural selection." ”

“ Grant that among a people endowed with musical faculty to a certain degree, spontaneous variation will occasionally produce men possessing it in a higher degree; it cannot be granted that spontaneous variation accounts for the frequent production, by such highly-endowed men, of men still more highly endowed. ”

“ To prove the transmission of those structural peculiarities which have resulted from functional peculiarities, is, for several reasons, comparatively difficult. Changes produced in the sizes of parts by changes in their amounts of action, are mostly unobtrusive. A muscle which has increased in bulk is usually so obscured by natural or artificial clothing, that unless the alteration is extreme it passes without remark. Such nervous developments as are possible in the course of a single life, cannot be seen externally. ”

“ Darwin, Youatt says the principle of selection "enables the agriculturist not only to modify the character of his flock but to change it altogether." Lord Somerville, speaking of what breeders have done for sheep, says:—"It would seem that they have chalked upon a wall a form perfect in itself and then given it existence." ”

“ But it is not equally manifest that, on this hypothesis, alterations of structure caused by alterations of function must be transmitted to offspring. It is not obvious that change in the form of a part, caused by changed action, involves such change in the physiological units throughout the organism that these, when groups of them are thrown off in the shape of reproductive centres, will unfold into organisms that have this part similarly changed in form. ”

“ There is no explanation but that the habitual association of certain cadences of speech with certain emotions, has slowly established in the race an organized and inherited connection between such cadences and such emotions; that the combination of such cadences, more or less idealized, which constitutes melody, has all along had a meaning in the average mind, only because of the meaning which cadences had acquired in the average mind ”

“ Hence the immense prices given for successful racers, bulls of superior forms, sheep that have certain desired peculiarities. Hence the careful record of pedigrees of high-bred horses and sporting dogs. ”

“ Still more if we look back to those early stages through which the faculty must have passed before definite perception of melody was arrived at, we fail to see how those possessing the rudimentary faculty in a somewhat greater degree than the rest, would thereby be enabled the better to maintain themselves and their children. ”

“ From an interrogation of one of them, it appeared that he belonged to a family all the male members of which have been dwarfs for several generations. They marry ordinary native girls, and the female children grow up like those of other people. The males, however, though they develop at the normal rate until they reach the age of six, then cease to grow, and become dwarfs. ”

“ The torturing practice of artificially arresting the growth of the feet, could never have become established among the ladies of China, had they not seen that a small foot was significant of superior rank—that is of a luxurious life—that is of a life without bodily labour. There is evidence, too, that modifications of the eyes, caused by particular uses of the eyes, are inherited. Short sight appears to be uncommon among peasants ”

“ The great and inherited development of the udders in cows and goats in countries where they are habitually milked, in comparison with the state of these organs in other countries, is another instance of the effect of use. ”

“ But the best examples of inherited modifications produced by modifications of function, occur in mankind. To no other cause can be ascribed the rapid metamorphoses undergone by the British races when placed in new conditions. ”

“ While, however, the general truth that organisms of a given type uniformly descend from organisms of the same type, is so well established by infinite illustrations as to have assumed the character of an axiom; it is not universally admitted that non-typical peculiarities are inherited. ”

“ From all sides evidence may be gathered showing a like persistence of varieties among animals. We have our distinct breeds of sheep, our distinct breeds of cattle, our distinct breeds of horses: each breed maintaining its characteristics. ”

“ It is admitted that consumption may be produced by conditions very unfavourable to life; and unless it is held that the disease so produced differs from the disease when inherited, the conclusion must be that here, too, there is a transmission of functionally-produced organic changes. ”

“ It is well known that several animals belonging to the most different classes, which inhabit the caves of Styria and of Kentucky, are blind. In some of the crabs the footstalk of the eye remains, though the eye is gone ”

“ On the average, the children of marriages with others not similarly endowed, will be less distinguished rather than more distinguished. The most that can be expected is that this unusual amount of faculty shall re-appear in the next generation undiminished. ”

“ In the United States the descendants of the immigrant Irish lose their Celtic aspect, and become Americanized. This cannot be ascribed to mixture, since the feeling with which Irish are regarded by Americans prevents any considerable amount of intermarriage. ”

“ This power is sufficiently remarkable in cases where a lost limb or tail is replaced, but it is still more remarkable in cases where, as among some annelids, the pieces into which an individual is cut severally complete themselves by developing heads and tails, or in cases like that of the Holothuria, which having, when alarmed, ejected its viscera, reproduces them. ”

“ The average Italian face continues to be unlike the faces of northern nations. The French character is now, as it was centuries ago, contrasted in sundry respects with the characters of neighbouring peoples. ”

“ Brown states that he "has in many instances observed in the case of individuals whose complexion and general appearance has been modified by residence in hot climates, that children born to them subsequently to such residence, have resembled them rather in their acquired than primary mien." ”