Scientists declare that they are now able to trace the development of the two diverging2 lines of sex-demarcation from the time of their separation, or from the time when these principles were confined within one and the same individual. In order to understand the origin of sex, it becomes necessary to recall, briefly3, the theory of the development of life on the earth as set forth4 by the savants.
As science deals only with matter, a mechanical theory of the universe is inevitable5. As science is wholly materialistic6, it is perfectly7 consistent in its declaration that the senses and the intellect constitute the only means whereby truth may be discovered. Modern philosophy, on the other4 hand, which deals less with matter itself than with the causes which underlie8 the development of matter, affirms that a character has been developed in human beings which in its capacity to discern truth, far transcends9 the intellect. That character is intuition. But as we are dealing10 only with scientific observations, philosophical11 speculations12 do not here concern us.
The fundamental idea, which must necessarily lie at the bottom of all natural theories of development, is that of a gradual development of all (even the most perfect) organisms out of a single, or out of a very few, quite simple, and quite imperfect original beings, which came into existence, not by supernatural creation, but by spontaneous generation.1
According to the theory of evolution as elaborated by scientists, the history of man begins with small animated13 particles, or Monera, which appeared in the primeval sea. These marine14 specks15 were albuminous compounds of carbon, generated by the sun’s heat, which made their appearance as soon as the mists which enveloped16 the earth were sufficiently17 cleared away to permit the rays of the sun to penetrate18 them and reach the surface of the globe. Concerning the origin of the principle of life which these particles contained, or regarding the development of organic bodies from inorganic19 substances, the more timid among naturalists20 declare that in the present state of5 human knowledge it is impossible to know anything, while others of them, more bold, or more confident of the latent powers of the human intellect, after having elaborated a natural or mechanical explanation for the development of all organic forms, are not disposed to accept a supernatural theory for the beginning of life. For example, since organic structures represent the development of matter according to laws governing the chemical, molecular22, and physical forces inherent in it, it is believed that the gulf23 separating organic and inorganic substances is not so difficult to span as has hitherto been supposed. Among those who hold this view may be ranked the celebrated24 naturalist21, Ernst Haeckel.
Regarding the phenomena25 of life this writer observes: “We can demonstrate the infinitely26 manifold and complicated physical and chemical properties of the albuminous bodies to be the real cause of organic or vital phenomena.”2 Indeed, in whatever manner the vital force within them originated, naturalists agree that from these particles have been derived27 all the forms, both animal and vegetable, which have ever existed upon the earth.
As speculations concerning the origin of matter lie without the domain28 of natural or scientific inquiry29, they form no part of the investigations30 of the naturalist. So far as is known, matter is eternal, and all that may be learned concerning6 it must be gleaned31 by observing the changes, chemical and molecular, through which it is manifested. By those who have observed the laws which govern the manifold changes in matter, the fact is declared that the various manifestations32 in form and substance constitute the only creation of which we may have any knowledge; and, moreover, that the genesis of existence is going on as actively33 in our time as at any previous period in the history of matter. So far as human knowledge extends, no particle of matter has ever been created and none ever destroyed. This continuous process of transmutation of substance and change of form, in other words the phenomena designated Life, may have been in operation during all the past, and may continue forever.
As all speculations concerning the origin of matter have been unavailing, so all attempts to solve the problem of the origin of life have proved futile34. The experiments recently carried on in the Rockefeller Institute, in which by means of chemical processes detached organs from the bodies of animals have been made to perform their normal functions, are interesting and instructive, but these experiments furnish no clue to the origin of the force which animates35 living organic matter. Why the nucleated cells which we call a heart should pulsate36 whilst those which we call a liver should secrete37 bile, nobody knows.
That all life on the earth has been derived from one, or at most from a few original forms, is said7 to be proved by ontogeny, or the history of the germ, which in its development passes through a number of the forms which mark the ascending38 scale of life.
Through the study of comparative anatomy39, the fact has been discovered that the individuals composing the various orders of the great vertebrate series are all moulded “on the same general plan”; that up to a certain stage in the development of the several germs—for instance those of the man, the ape, the horse, the dog, etc.,—they are not distinguishable the one from the other, and that it is only at a later stage of development that they take on the peculiarities40 belonging to their own special kind. The number and variety of forms which appear in the animal and vegetable world make it difficult to conceive of the idea that all have sprung from one, or at most from a few original types, yet the chain of evidence in support of this theory seems quite complete.
Natural Selection, by which it is demonstrated that organized matter must move forward simply through the chemical and physical forces inherent in it, furnishes a key to all the phenomena of life, both animal and vegetable, which have ever appeared on the earth. Natural Selection, we are told, depends for its operation on the interaction of two processes or agencies, namely, Inheritance and Adaptation. Through Inheritance germs receive from their parents a plastic form which, as all development is a function of external physical8 conditions, is itself nothing more than a “manifestation of the remains41 of antecedent physical impressions.” This inherited form causes them to go forward in a predestined course, while through Adaptation there is a constant tendency to change that predestined form imposed upon them by their parents to one better suited to their changing physical conditions.
According to the theory of Natural Selection, organic structures vary to meet the requirements of changed conditions; or, when existing circumstances are such that they are forced into new and unusual modes of life, they branch off into different directions; thus new varieties are formed, or possibly new species. Such portions of a group, however, as remain sheltered from conditions unsuited to their present line of development, retain their ancient forms. This change of structure by which organisms or portions of organic bodies are modified so as to perform more complicated functions, or those better suited to their environment, is denominated differentiation42; hence the degree of differentiation attained43 by a structure determines the stage of development which it has reached.
But to return to our single-celled animal—the simplest form of life on the earth. Except that by the action of the surrounding forces its surface has become somewhat hardened, this little animal is the same throughout, in other words, it is homogeneous. The hardening of the outer portion9 constitutes the first process of differentiation, and therefore the first step in the order of progress.
Comparing the simplest form of life, the little carbon-sac found in the sea, with the germ from which animals and plants are derived, Haeckel says:
Originally every organic cell is only a single globule of mucus, like a Moneron, but differing from it in the fact that the homogeneous albuminous substance has separated itself into two different parts, a firmer albuminous body, the cell-kernel (nucleus44), and an external, softer albuminous body, the cell-substance or body (protoplasma).3
From its body, which, when at rest, is nearly spherical45, it is almost constantly casting forth certain “finger-like processes” which are as quickly withdrawn46, only to reappear on some other portion of its surface. The small particles of albuminous matter with which it comes in contact adhere to it, or are drawn47 into its semi-fluid body by displacement48 of the several albuminous particles of which it is composed, and are there digested, being “absorbed by simple diffusion49.” Its only activity consists in supplying itself with nourishment50, and even during this process it is said to display a negative or passive quality rather than real action. The particles absorbed that are not assimilated, are expelled through the surface of10 the body in the same manner as they are taken into it.
At first, we are told, our animal is only a simple cell, in fact that it is not a perfect cell, for as yet the cell-kernel or nucleus has not been separated from the cell-substance or protoplasm. When its limit of size has been reached it multiplies by self-division, or by simply breaking into parts, each part performing the same functions of nutrition and propagation as its predecessor51. Later, however, when a parent cell bursts, the newly developed cells no longer separate from it, but, by cohering52 to it and to each other, form a cluster of nucleated cells, while around this aggregation53 of units is formed a wall. Still its food is absorbed. Subsequently, however, a mouth and prehensile54 organs for seizing its food are developed, and the divisions between the cells are converted into channels or pipes through which nourishment is conveyed to every part of the body. In process of time, limbs for locomotion55 appear, together with bones for levers, and muscles for moving them. Finally, a brain and a heart are evolved, and although at first the heart appears as only a simple pulsating56 vessel57, later this animal finds itself the possessor of a perfect system of digestion58, circulation, and excretion, by which food, after having been changed into blood and a?rated or purified by processes carried on in the system, is pumped to every part of the body. With the formation of different chemical combinations, and11 the development, through increasing specialization of the various kinds of tissues, and finally of the various organs, that intimate relationship observed between the parts in homogeneous and less differentiated59 structures no longer exists; hence, in response to the demand for communication between the various organs, numberless threads or fibres begin to stretch themselves through the muscles, and collecting in knots or centres in the brain and spine60, establish instantaneous communication between the different parts, and convey sensation and feeling throughout the entire organism.
A division of labour has now been established, and each organ, being in working order and fashioned for its own special use, performs its separate functions independently, although its activity is co-ordinated with that of all other organs in the structure.
This far in the history of life on the earth sex has not been developed, or, more correctly stated, as the two sexes have not been separated, our animal is still androgynous or hermaphrodite—the reproductive functions being confined in one and the same individual. Within this little primeval animal, the progenitor61 of the human race, lay not only all the possibilities which have thus far been realized by mankind, but within it were embodied62 also the “promise and potency” of all that progress which is yet to come, and of which man himself, in his present undeveloped state, may have only a dim foreshadowing.
12
From the time of the appearance of life on the earth to that of the separation of the sexes, myriads63 of centuries may have intervened. Only when through a division of labour these elements became detached, and the special functions of each were confided64 to two distinct and separate individuals, did the independent history of the female and male sexes begin.
No fact is more patent, at the present time, than that sex constitutes the underlying principle throughout nature. Although it may not be said of the simplest forms of life that sexual difference has been established, yet we are assured that among the ciliated Infusorians “male and female nuclear elements have been distinguished65.” This primitive66 condition, however, is supposed to be rather a state antecedent to sex than a union of sexes in one organism. Among all the higher orders of life, whether animal or vegetable, the sex elements, female and male, are recognized as the two great factors in creation.
As, among all the animals in which there has been a separation of sexes, there has been established a division of labour, the consequent specialization of organs and the differentiation of parts form the true line of demarcation in the march of the two diverging columns. Doubtless in the future, when our knowledge of the history of life on the earth has become more extended, it will be found that it is only by tracing the processes of differentiation throughout the two entire13 lines of development that we may hope to unravel67 all the mysteries bound up in the problem of sex, or to understand the fundamental differences in character and constitution caused by this early division of labour.
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1
underlying
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| adj.在下面的，含蓄的，潜在的 | |
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2
diverging
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| 分开( diverge的现在分词 )； 偏离； 分歧； 分道扬镳 | |
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3
briefly
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| adv.简单地，简短地 | |
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4
forth
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| adv.向前；向外，往外 | |
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5
inevitable
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| adj.不可避免的，必然发生的 | |
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6
materialistic
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| a.唯物主义的，物质享乐主义的 | |
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7
perfectly
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| adv.完美地，无可非议地，彻底地 | |
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8
underlie
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| v.位于...之下，成为...的基础 | |
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9
transcends
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| 超出或超越（经验、信念、描写能力等）的范围( transcend的第三人称单数 )； 优于或胜过… | |
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10
dealing
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| n.经商方法，待人态度 | |
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11
philosophical
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| adj.哲学家的，哲学上的，达观的 | |
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12
speculations
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| n.投机买卖( speculation的名词复数 )；思考；投机活动；推断 | |
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13
animated
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| adj.生气勃勃的，活跃的，愉快的 | |
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14
marine
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| adj.海的；海生的；航海的；海事的；n.水兵 | |
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15
specks
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| n.眼镜；斑点，微粒，污点( speck的名词复数 ) | |
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16
enveloped
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| v.包围，笼罩，包住( envelop的过去式和过去分词 ) | |
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17
sufficiently
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| adv.足够地，充分地 | |
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18
penetrate
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| v.透(渗)入；刺入，刺穿；洞察，了解 | |
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19
inorganic
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| adj.无生物的；无机的 | |
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20
naturalists
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| n.博物学家( naturalist的名词复数 )；（文学艺术的）自然主义者 | |
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21
naturalist
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| n.博物学家(尤指直接观察动植物者) | |
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22
molecular
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| adj.分子的；克分子的 | |
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23
gulf
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| n.海湾；深渊，鸿沟；分歧，隔阂 | |
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24
celebrated
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| adj.有名的，声誉卓著的 | |
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25
phenomena
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| n.现象 | |
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26
infinitely
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| adv.无限地，无穷地 | |
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27
derived
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| vi.起源；由来；衍生；导出v.得到( derive的过去式和过去分词 )；（从…中）得到获得；源于；（从…中）提取 | |
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28
domain
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| n.(活动等)领域，范围；领地，势力范围 | |
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29
inquiry
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| n.打听，询问，调查，查问 | |
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30
investigations
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| （正式的）调查( investigation的名词复数 )； 侦查； 科学研究； 学术研究 | |
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31
gleaned
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| v.一点点地收集（资料、事实）( glean的过去式和过去分词 )；（收割后）拾穗 | |
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32
manifestations
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| n.表示，显示（manifestation的复数形式） | |
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33
actively
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| adv.积极地，勤奋地 | |
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34
futile
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| adj.无效的，无用的，无希望的 | |
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35
animates
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| v.使有生气( animate的第三人称单数 )；驱动；使栩栩如生地动作；赋予…以生命 | |
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36
pulsate
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| v.有规律的跳动 | |
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37
secrete
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| vt.分泌；隐匿，使隐秘 | |
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38
ascending
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| adj.上升的，向上的 | |
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39
anatomy
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| n.解剖学，解剖；功能，结构，组织 | |
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40
peculiarities
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| n. 特质, 特性, 怪癖, 古怪 | |
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41
remains
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| n.剩余物，残留物；遗体，遗迹 | |
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42
differentiation
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| n.区别，区分 | |
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43
attained
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| （通常经过努力）实现( attain的过去式和过去分词 )； 达到； 获得； 达到（某年龄、水平、状况） | |
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44
nucleus
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| n.核，核心，原子核 | |
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45
spherical
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| adj.球形的；球面的 | |
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46
withdrawn
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| vt.收回；使退出；vi.撤退，退出 | |
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47
drawn
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| v.拖，拉，拔出；adj.憔悴的，紧张的 | |
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48
displacement
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| n.移置，取代，位移，排水量 | |
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49
diffusion
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| n.流布；普及；散漫 | |
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50
nourishment
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| n.食物，营养品；营养情况 | |
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51
predecessor
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| n.前辈，前任 | |
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52
cohering
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| v.黏合( cohere的现在分词 )；联合；结合；（指看法、推理等）前后一致 | |
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53
aggregation
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| n.聚合，组合；凝聚 | |
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54
prehensile
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| adj.（足等）适于抓握的 | |
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55
locomotion
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| n.运动，移动 | |
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56
pulsating
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| adj.搏动的，脉冲的v.有节奏地舒张及收缩( pulsate的现在分词 )；跳动；脉动；受（激情）震动 | |
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57
vessel
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| n.船舶；容器，器皿；管，导管，血管 | |
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58
digestion
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| n.消化，吸收 | |
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59
differentiated
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| 区分，区别，辨别( differentiate的过去式和过去分词 )； 区别对待； 表明…间的差别，构成…间差别的特征 | |
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60
spine
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| n.脊柱，脊椎；(动植物的)刺；书脊 | |
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61
progenitor
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| n.祖先，先驱 | |
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62
embodied
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| v.表现( embody的过去式和过去分词 )；象征；包括；包含 | |
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63
myriads
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| n.无数，极大数量( myriad的名词复数 ) | |
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64
confided
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| v.吐露（秘密，心事等）( confide的过去式和过去分词 )；（向某人）吐露（隐私、秘密等） | |
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65
distinguished
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| adj.卓越的，杰出的，著名的 | |
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66
primitive
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| adj.原始的；简单的；n.原(始)人，原始事物 | |
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67
unravel
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| v.弄清楚（秘密）；拆开，解开，松开 | |
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