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CHAPTER I
ОглавлениеTHE PROBLEM DEFINED
What is sex? Asexual and mixed reproduction; Origin of sexual reproduction; Advantage of sex in chance of survival; Germ and body cells; Limitations of biology in social problems; Sex always present in higher animals; Sex in mammals; The sex problem in the human species; Application of laboratory method.
Sex, like all complicated phenomena, defies being crowded into a simple definition. In an animal or plant individual it is expressed by and linked with the ability to produce egg- or sperm-cells (ova or spermatozoa). Sexual reproduction is simply the chain of events following the union of the egg and sperm to produce a new individual. Looked at from another angle, it is that sort of reproduction which requires two differentiated individuals: the male, which produces spermatoza, and the female, which produces ova. In the case of very simple forms, it would be simply the union or conjugation of a male and a female individual and the reproductive process involved. Where there is no differentiation into male and female there is no sex.
An individual which produces both sperm-and egg-cells within its body is termed an hermaphrodite. Very few hermaphrodites exist among the vertebrates, although they may be found in one or two species (e.g., the hagfish). There are no truly hermaphroditic mammals, i.e., individuals in which both the male and the female germ cells function, except perhaps in rare instances.
Sexless or asexual reproduction assumes various forms. What is usually considered the most primitive of these is fission or simple division, in which the cell divides into two equal, identical parts. There is of course no suggestion of sex here. It is fairly safe to assume that life began thus in the world, as neuter or sexless—i.e., with no suggestion of either maleness or femaleness.[A]
This asexual type of reproduction has been misinterpreted by a whole school of non-biological writers, who have followed the lead of Lester F. Ward, in his classification of these neuter-organisms as females. Ward says ("Pure Sociology," Ch. 14): "It does no violence to language or science to say that life begins with the female organism and is carried on a long distance by means of females alone. In all the different forms of asexual reproduction from fission to parthenogenesis, the female may in this sense be said to exist alone and perform all the functions of life including reproduction. In a word, life begins as female" (p. 313). Adding to this statement the assertion that the male developed at first as a mere parasite, in the actual, physical sense, Ward proceeds to build up his famous Gynæcocentric Theory, which is familiar to all students of social science, and need not be elaborated here. It is obvious that a thorough biological knowledge destroys the fundamental concept on which this theory is founded, for there is no doubt that life begins as neuter or sexless, and not as female.
There are a number of other forms of asexual reproduction, or the "vegetative type" (Abbott's term, which includes fission, budding, polysporogonia and simple spore formation). Budding (as in yeast) and spore formation are familiar to us in plants. Such forms are too distant from man, in structure and function, for profitable direct comparison. Especially is this true with respect to sex, which they do not possess.
Parthenogenesis includes very diverse and anomalous cases. The term signifies the ability of females to reproduce in such species for one or a number of generations without males. Many forms of this class (or more strictly, these classes) have apparently become specialized or degenerated, having once been more truly sexual. Parthenogenesis (division and development of an egg without the agency of male sperm) has been brought about artificially by Jacques Loeb in species as complicated as frogs.[1][2] All the frogs produced were males, so that the race (of frogs) could not even be theoretically carried on by that method.
The origin of sexual reproduction in animals must have been something as follows: The first method of reproduction was by a simple division of the unicellular organism to form two new individuals. At times, a fusion of two independent individuals occurred. This was known as conjugation, and is seen among Paramecia and some other species to-day. Its value is probably a reinvigoration of the vitality of the individual. Next there was probably a tendency for the organism to break up into many parts which subsequently united with each other. Gradually some of these uniting cells came to contain more food material than the others. As a result of their increased size, they possessed less power of motion than the others, and in time lost their cilia (or flagella) entirely and were brought into contact with the smaller cells only by the motion of the latter. Finally, in colonial forms, most of the cells in the colony ceased to have any share in reproduction, that function being relegated to the activities of a few cells which broke away and united with others similarly adrift. These cells functioning for reproduction continued to differentiate more and more, until large ova and small, motile spermtozoa were definitely developed.
The clearest evidences as to the stages in the evolution of sexual reproduction is found in the plant world among the green algæ.[3] In the lower orders of one-celled algæ, reproduction takes place by simple cell division. In some families, this simple division results in the production of several new individuals instead of only two from each parent cell. A slightly different condition is found in those orders where the numerous cells thus produced by simple division of the parent organism unite in pairs to produce new individuals after a brief independent existence of their own. These free-swimming cells, which apparently are formed only to reunite with each other, are called zoöspores, while the organism which results from their fusion is known as a zygospore. The zygospore thus formed slowly increases in size, until it in its turn develops a new generation of zoöspores. In still other forms, in place of the zoöspores, more highly differentiated cells, known as eggs and sperms, are developed, and these unite to produce the new individuals. Both eggs and sperms are believed to have been derived from simpler ancestral types of ciliated cells which were similar in structure and closely resembled zoöspores.[A]
This evidence, which points to the conclusion that in the early origin of sexual reproduction the males and females were differentiated and developed from a uniform type of ancestral cell, quite controverts Ward's point that the male originated as a kind of parasite.
Having once originated, the sexual type of reproduction possessed a definite survival value which assured its continuation. Sex makes possible a crossing of strains, which evidently possesses some great advantage, since the few simple forms which have no such division of reproductive functions have undergone no great development and all the higher, more complicated animals are sexual. This crossing of strains may make possible greater variety, it may help in crossing out or weakening variations which are too far from the average, or both.
Schäfer[4] thinks that an exchange of nuclear substance probably gives a sort of chemical rejuvenation and very likely stimulates division. At any rate, the groups in which the reproductive process became thus partitioned between two kinds of individuals, male and female, not only survived, but they underwent an amazing development compared with those which remained sexless.
There came a time in the evolution of the groups possessing sexual reproduction, when increasing specialization necessitated the division into reproductive and non-reproductive cells. When a simple cell reproduces by dividing into two similar parts, each developing into a new individual like the parent, this parent no longer exists as a cell, but the material which composed it still exists in the new ones. The old cell did not "die"—no body was left behind. Since this nuclear substance exists in the new cells, and since these generations go on indefinitely, the cells are in a sense "immortal" or deathless. In a one-celled individual, there is no distinction between germinal and bodily functions. In the more complicated organisms, however, there are innumerable kinds of cells, a few (the germ cells) specialized for reproduction, the others forming the body which eats, moves, sees, feels, and in the case of man, thinks. But the germ-cells or germplasm continue to be immortal or deathless in the same sense as in the simplest organisms. The body, in a historical sense, grew up around the germ-cells, taking over functions a little at a time, until in the higher animals nutrition and other activities and a large part even of the reproductive process itself is carried on by body-cells.
When we think of a man or woman, we think of an individual only one of whose innumerable activities—reproduction—is carried on by germ-cells, and this one only at the very beginning of the life of a new individual. Human societies, needless to remark, are not organized by germplasms, but by brains and hands—composed of body cells. If these brains and hands—if human bodies—did not wear out or become destroyed, we should not need to trouble ourselves so much about the germplasm, whose sole function in human society is to replace them.
Since the individual human bodies and minds which seek after the things to which we mortals attach value—moral worth, esthetic and other pleasure, achievement and the like—do have to be replaced every few years, the germplasms from which new individuals must come have always been and always will be of fundamental importance. It is always the product of the germplasm which concerns us, and we are interested in the germ-cells themselves only in relation to their capacity to produce individuals of value to society.
So let us not go erring about in the philosophical ether, imagining that because the amoeba may not be specialized for anything over and above nutrition and reproduction that these are necessarily the "main business" or "chief ends" of human societies. Better say that although we have become developed and specialized for a million other activities we are still bound by those fundamental necessities. As to "Nature's purposes" about which the older sex literature has had so much to say, the idea is essentially religious rather than scientific. If such "purposes" indeed exist in the universe, man evidently does not feel particularly bound by them. We do not hesitate to put a cornfield where "Nature" had a forest, or to replace a barren hillside by the sea with a city.
Necessities and possibilities, not "purposes" in nature, claim our attention—reproduction being one of those embarrassing necessities, viewed through the eyes of man, the one evaluating animal in the world. Thus in reasoning from biology to social problems, it is fundamental to remember that man as an animal is tremendously differentiated in functions, and that most of the activities we look upon as distinctively human depend upon the body rather than the germ-cells.
It follows that biology is the foundation rather than the house, if we may use so crude a figure. The solidity of the foundation is very important, but it does not dictate the details as to how the superstructure shall be arranged.
Civilization would not be civilization if we had to spend most of our time thinking about the biological basis. If we wish to think of "Nature's" proscriptions or plans as controlling animal life, the anthropomorphism is substantially harmless. But man keeps out of the way of most of such proscriptions, has plans of his own, and has acquired considerable skill in varying his projects without running foul of such biological prohibitions.
It is time to abandon the notion that biology prescribes in detail how we shall run society. True, this foundation has never received a surplus of intelligent consideration. Sometimes human societies have built so foolishly upon it that the result has been collapse. Somebody is always digging around it in quest of evidence of some vanished idyllic state of things which, having had and discarded, we should return to. This little excursion into biology is made in the full consciousness that social mandates are not to be found there. Human projects are the primary material of social science. It is indispensable to check these against biological fact, in order to ascertain which are feasible and which are not. The biological basis may help in explaining old social structures or in planning new ones; but much wild social theory has been born of a failure to appreciate the limitations of such material.
All the so-called higher animals, mammals and others, are divided into two sexes, male and female. Besides the differentiation of germ-cells there are rather obvious differences in the bodies of the two sexes. In common with many other mammals, the human male has a larger and stronger body, on an average, than has the human female. This is true also of the anthropoid apes, the species which most resemble man physically and are commonly supposed to be his nearest blood relatives in the animal kingdom. It has been true of man himself as far back as we have any records.
Such differences are only superficial—the real ones go deeper. We are not so much interested in how they originated in the world as in how they do come about in the individual. At least, we can come a good deal nearer ascertaining the latter than the former. In either case, our real purpose is to determine as nearly as possible what the unlikeness really consists of and so help people to sensibly make up their minds what can be done about it.
To define sex with rigid accuracy as the term applies to human beings, it is necessary to tell what it is in mammals, since man is a mammal. The presence of distinct body-cells is not peculiar to mammals, but there is one respect in which these latter are quite different from non-mammals: A mammalian individual, beginning like a non-mammal with a fertilized egg, has a period of intra-maternal development which a non-mammal has not. That is, a non-mammalian is a fertilized egg plus its parental (or extra-parental) environment; but a mammalian individual is a fertilized egg, plus its intra-maternal environment, plus its non-parental environment.
Here in a nutshell is the biological basis of sex problem in human society. Human individuals do wear out and have to be replaced by reproduction. In the reproductive process, the female, as in mammals generally, is specialized to provide an intra-maternal environment (approximately nine months in the human species) for each new individual, and lactation or suckling afterward. The biological phase of the sex problem in society consists in studying the nature of that specialization. From the purely sociological standpoint, the sex problem concerns the customs and institutions which have grown up or may grow up to meet the need of society for reproduction.
The point which most concerns us is in how far biological data can be applied to the sex problem in society. Systematic dissections or breeding experiments upon human beings, thought out in advance and under control in a laboratory, are subject to obvious limitations. Surgical operations, where careful data are kept, often answer the same purpose as concerns some details; but these alone would give us a fragmentary record of how a fertilized egg becomes a conscious human being of one sex or the other. The practice of medicine often throws light on important points. Observation of abnormal cases plays its part in adding to our knowledge. Carefully compiled records of what does occur in inheritance, while lacking many of the checks of planned and controlled experiments, to some extent take the place of the systematic breeding possible with animals. At best, however, the limitations in experimentation with human subjects would give us a rather disconnected record were it not for the data of experimental biology.
How may such biological material be safely used? Indiscriminately employed, it is worse than useless—it can be confusing or actually misleading. It is probably never safe to say, or even to infer directly, that because of this or that animal structure or behaviour we should do thus and so in human society. On this point sociology—especially the sociology of sex—must frankly admit its mistakes and break with much of its cherished past.
The social problem of sex consists of fitting the best possible institutions on to the biological foundation as we find it in the human species. Hence all our reasoning about which institution or custom is preferable must refer directly to the human bodies which compose society. We can use laboratory evidence about the bodies of other animals to help us in understanding the physical structure and functions of the human body; but we must stop trying to apply the sex-ways of birds, spiders or even cows (which are at least mammals) to human society, which is not made up of any of these.
It is possible to be quite sure that some facts carefully observed about mammals in a biological laboratory apply to similar structures in man, also a mammal. Because of this relationship, the data from medicine and surgery are priceless. Thus we are enabled to check up our systematic experimental knowledge of animals by an ascertained fact here and there in the human material, and to get a fairly exact idea of how great the correspondence actually is. Gaps thus filled in are narrow enough, and our certainty of the ground on either side sufficiently great, to give a good deal of justifiable assurance.
If we use our general biological evidence in this way, merely to help in clearing up points about human biology, we need not be entirely limited to mammals. Some sex phenomena are quite general, and may be drawn from the sexual species most convenient to study and control in experiments. When we get away from mammalian forms, however, we must be very sure that the cases used for illustrations are of general application, are similar in respect to the points compared, or that any vital differences are understood and conscientiously pointed out.
Too much stress cannot be laid upon the point that such animal data, carefully checked up with the human material, cannot safely be used for any other purpose than to discover what the facts are about the human body. When the discussion of human social institutions is taken up in Part II, the obvious assumption will always be that these rest upon human biology, and that we must not let our minds wander into vague analogies concerning birds, spiders or crustacea.
BIBLIOGRAPHY FOR CHAPTER I
Loeb, Jacques. Artificial Parthenogenesis and Fertilization. Chicago, 1913.
Loeb, Jacques. The Organism as a Whole. N.Y., 1916, p. 125—brief summary of results of [1].
Bower, Kerr & Agar. Sex and Heredity. N.Y., 1919, 119 pp.
Schäfer, E.A. Nature, Origin and Maintenance of Life. Science, n.s., Vol. 36, pp. 306 f., 1912.
5.
Guyer, M.F. Being Well-Born. Indianapolis, 1916; p. 123.
