The phenomenon of virgin3 birth is one of profound mystery. The existence of so astonishing a mode of reproduction was an established belief among the ancients, though they could have had no means of demonstrating the faith that was in them. But these men saw no difficulty in ascribing to the females of their own race this faculty4 of producing offspring without the intervention5 of a male. One suspects, indeed, that there was no solid foundation whatever for this belief in these miraculous6 powers: they lived in credulous7 times, and the recorded occurrences of these, even to them, irregular births are to be regarded as devised to afford a convenient means of escape from the consequences of lapses8 from the path of virtue9. Yet, incredible as it may appear, there are not wanting to-day both men and women who affect to believe that this mode of reproduction obtains still among the human race, in certain exceptional cases; and further, they profess10 a conviction 297that in the future it may become the normal mode, males, in consequence, becoming unnecessary! Such professions of faith are made only by the ignorant, or by those who trade on human credulity. Parthenogenesis not only does not occur in the human race, but it does not even occur in any member of the great group of vertebrates of which man himself stands at the head, and it never will occur.
Those near relations of the Bees, the Ants, afford a further insight into this strange method of reproduction. Each community in the case of these insects harbours not one, but many queens. The nuptial11 flight, like that of the Bees, takes place in mid-air; but myriads12 of both sexes participate therein, forming a filmy, ever-shifting cloud, now rising, now falling, in the shimmering14 sunlight. At no time do they seek to attain15 the altitude, or the privacy, so strenuously16 striven for by the Bees. But in the case of the latter there is but one female, and her life is precious. She must seek sanctuary17 for the consummation of her marriage in the highest heavens, beyond the risk of instant destruction by insect-eating birds; for though thousands of suitors accompany her, she rises above them all, save one or two, and hence would form an easy mark. With the Ants there are thousands of queens, and the destruction of a few hundreds more or less is rather an advantage to the species than otherwise. On their return to earth the males die: their life’s work is accomplished18. The females, or as we must call them, the queens, on the other hand, have a long life before them; far longer than that of the queen bee. But for them the joys of flight are restricted to this one brief revel19, for, no sooner have they reached298 terra firma, than they renounce20, as it were, the pleasures of life to devote themselves entirely21 to the work of reproduction. And as if to make all regrets vain, to stamp out all possible temptation to desert their vows22, they tear off their gauzy wings, and with them goes all hope of fertile repentance23: for the rest of this life their home is underground.
Each queen, on her descent, departs a separate way, and hard is the road before her. She left the parental24 nest well-fed, and in good liking25, her body well, stored with food in the shape of fat and the now useless, bulky, wing-muscles, and with this, her only dowry, she starts the formation of a new colony out of her own substance. Her first task is to form a burrow26, and at the end of this she fashions a small chamber27. This done, she closes the mouth of the burrow and cuts herself off from the world. The labour of this burrowing28 is so severe that it often wears away her teeth, her only tools, and the hairs from her body. In this retreat she now waits patiently for the eggs within her to ripen29, which may take months to accomplish: she is still fasting, or, rather, feeding upon herself. When at last the eggs are laid and hatched, she feeds her children on saliva30, the very juice of her body, for she is still fasting. Nor is the strain relaxed till the larv? undergo their transformation31 into pup?, and, after a brief sleep, emerge as “worker” Ants, puny32 in stature33 owing to the poorness of their food during larval life. In some species this fast may last for ten long months. So soon, however, as these little workers emerge, like dutiful daughters they make their way to the outer world, and go forth34 in search of food, which they share with their now exhausted35 mother. But, besides, they enlarge the original chamber, and drive galleries in all299 directions to provide accommodation for the vast population that is soon to crowd the thoroughfares. Meanwhile the queen resumes her task of producing more and yet more daughters, in whom she now displays not the slightest interest. Her elder children now bear away the eggs, and feed the young as they hatch. In course of time, as with the Bees, the task of wet-nurse falls on the youngest of the Ants, those who have just attained36 to anthood. For ten or fifteen years this queen-mother may continue her work of reproduction, a slave, indeed, to domesticity, with monotonous37 regularity38, checked only by the chill of autumn and the sleep of winter.
Those among our own race who profess to hail the prospect39 of a time when parthenogenesis shall be the normal mode of reproduction may well take the Ant as an awful warning. Their ambitions may overreach the mark. The poor queen becomes a slave to reproduction; children in myriads are born to her; even if she would she could not sustain her interest in them, she could not even recognize them as the fruit of her body. Her daughters are born to a lifelong drudgery40, her sons are mere41 fertilizing42 agents: for their only purpose in life is to perpetuate43 this awful thraldom44, this appalling45 prolificness47; and having accomplished this, they die forthwith. If there be any joy in this life it is drunk by the males alone. Thus does the female rule overreach itself. It is well, indeed, that the participants of the joyous48 nuptial flights dancing deliriously49 on gauzy wings in the glare of a summer day, have no foreknowledge of the long night that is to follow.
Unlike the Bees, the Ants may produce as many as five grades of workers, each of which have different duties towards the community. But the nature of those300 duties and the manner of the evolution of these types, are themes foreign to these pages: enough has been said already to indicate the nature of the problems they present when discussing the life-history of the Bees.
The subject of parthenogenesis need be pursued no further in this volume than is sufficient to bring out its retrograde character. It is a form of reproduction which may be limited to a small number of generations, as with the Aphides, or to a single generation alternating with normal sexual generations, as in many Cynipid? or Gall-flies, or it may be the only mode of reproduction, as in some other Gall-flies, some Saw-flies and some Crustacea, wherein no males have ever been seen. In some species this form of reproduction gives rise to females only—the Thelyotokous parthenogenesis of scientific text-books—as in the Saw-flies and Gall-flies, and the parasitic50 Tomognatbous. In some other Saw-flies, unfertilized queens and workers of Ants, Bees, and Wasps52, which occasionally produce offspring, the progeny53 is always male, and this is known as Arrhenotokous parthenogenesis. In one or two species of Saw-fly, e.g. Nematus curtispina, both males and females may be produced, when the species is said to be Deuterotokous.
In the case of the Aphides, winged males normally appear in large numbers at the end of the summer, and these fertilize51 the females; but if kept in a warm green-house, parthenogenetic reproduction may be sustained for as long as four years. Under quite normal circumstances these tiny insects show a singular range of variability, for egg-laying and viviparous individuals are met with; while winged and wingless generations appear301 sporadically54, apparently55 according to the abundance of food. The winged form is sometimes so abundant as to float about in swarms56 that darken the air. There are at least three kinds of males-winged males, wingless males with a functional57 mouth, and small wingless males which have no mouth, and, one need hardly say, are very short-lived. The Aphides are a feeble folk, individually, but collectively a power in the land, causing at times incalculable loss to the farmer and gardener; but on this head and on the subject of their strange habits, and sometimes adventurous58 lives as slaves in the service of Ants, no more than a hint may be dropped in these pages. But some such aids to faith seem to be necessary when those who are not tolerably familiar with these insects are told of their amazing fertility. Linn?us long since estimated, in regard to one species, that in the course of one year a single Aphis will give rise to a quintillion of descendants—all produced without the aid of a male. Every one of these females begins to reproduce within from ten to twenty days of her birth, but even this statement does not bring home the result of such an astounding61 fecundity62 like Huxley’s calculation which was carefully worked out. He estimated that the produce of a single female would, in the course of ten generations, supposing all the individuals to survive—and possess the normal fertility of their race—“contain more ponderable substance than five hundred millions of stout63 men: that is, more than the whole population of China.”
To explain such a riot of reproduction one might almost suppose these insects to be imbued64 with a dread65 of the impending66 dissolution of their race, and endowed with the power to avert67 such a calamity68 by these302 stupendous efforts; for it is evident that parthenogenesis confers quite extraordinary powers of raising the birth-rate. But then the normal mode of procreation is capable of achieving results quite as remarkable69. The queen Termite70 or White Ant, for instance—which, by the way, is no Ant, but a near relation of the Stone-flies—when in her prime will lay eggs at the rate of sixty a minute, or eighty thousand and upwards71 in the course of a day of twenty-four hours. But this unenviable mode of breaking the record is attended, surely, with some little inconvenience; for to attain to such fertility her abdomen72 increases until it attains73 something like two thousand times that of the workers of the community in which she lives. That the history of the queen Termite is unique of its kind is not surprising: indeed, such an amazing story could only be told of creatures which enjoyed the seclusion74 of a subterranean75 existence. Here, on a bare couch, with her Royal spouse76 beside her, she lies, a bloated, heaving mass, incapable77 of movement, depositing eggs with the rhythm of a machine, the mother of offspring which she will never see. A more unsightly picture of maternity it would be impossible to conceive: it is well, indeed, that it is hidden from the light of day. No such state of affairs could ever arise among creatures living an outdoor life, with enemies to avoid, and food to find.
The instances just surveyed, these extremes of the potentiality of procreation, are instructive in more ways than one. They are to be regarded as “excrescences” of reproduction, comparable to those “excrescences” of individual growth which we call “ornament78,” for example. Individuals on whom this fertility has settled, so to speak, are the victims of the machinery79 of sex and reproduction. Their amazing powers of multiplication303 are not of their own seeking, they are inherent manifestations80 of variations of growth, uncontrollable save by the machinery of Natural Selection. Incidentally such victims serve a useful purpose, for their myriad13 hosts afford food for hordes82 of other animals, which in turn are eaten. Little though we realize it, the well-being83 of the human race would suffer if these prolific46 creatures—the uncomplaining victims of that inexorable law which bids all living things “increase and multiply” or die—should cease to be; for with them would disappear a host of animals on whose existence man’s comfort more or less depends.
During the millions of years that have rolled by since the first appearance of life on the earth, who shall count the number of types which have been exterminated84 without leaving the faintest trace of their having ever existed? The survivors85 which have contrived86 to maintain a place in the sun present an infinite range of variation in colour, size, habit, and structure, as well as in emotions. These varied87 aspects are all so many facets88 of the mysterious phenomenon we call Life: and they are so many witnesses of the versatility89 of Life. Not the least mysterious feature of this Life is its faculty of reproduction, which expresses itself in an infinite variety of ways, defying all but the crudest forms of analysis. The evolution of sex has exercised the speculative90 ingenuity91 of some of the acutest students of Nature from the earliest times, and we are still far from a satisfactory solution of the problems it presents. Hermaphroditism and Parthenogenesis are commonly regarded as degenerate forms of reproduction, but it would probably be more correct to see in them exceptional modes of adaptation enabling such individuals to occupy304 niches92 in the world untenable to creatures of more conservative habit. That the peculiar93 “strains” of animal life have turned into backwaters which offer no opportunity or possibility of further advancement94 seems clear enough, but they are nevertheless interesting and instructive.
The parthenogenetic Crustacea and the Rotifers afford some good evidence of this adaptability—of the way in which creatures manage to cling to the skirts of life by reason of their power to survive the extremest tests of endurance. And this success has largely been due to some mysterious property of the germ-plasm enabling reproduction to take place through the female line alone, or in some cases with an occasional fillip from the intervention of males. Of the many marvellous things that could be related of these creatures but few instances can be cited here.
The case of the Brine Shrimp95 (Artemia salina) will afford an exceptionally good illustration because the facts can be tested by anyone who will take the trouble to make a simple experiment for himself. Those anxious to do this should dissolve eight ounces of Tidman’s sea-salt in a glass jar containing five pints96 of water, keeping the mixture well stirred till the salt is dissolved. It should be allowed to stand and be carefully watched. In about three days, with a pocket-lens, or even without, minute white specks97 will be seen moving with a jerky motion up and down the water. These are larval Brine Shrimps98. Now they must be fed. Take a piece of lettuce-leaf or any green stuff, and pound it up, or grind it up with a knife-blade on a plate with a little water, till the whole is reduced to the consistency99 of green paint; then empty this into the water. This must be305 done daily, or at any rate frequently. Quickly these tiny specks will grow into Brine Shrimps, translucent100 creatures nearly half an inch long, swimming about back downwards101 with a marvellously rhythmical102 movement of delicate feet. In all probability no males will be found, but, on the other hand, both sexes in almost equal numbers may be present. The males may readily be distinguished103 by their massive arms immediately behind the head, for the purpose of embracing the females.
Whence came these wonderful animals? The mystery is easily explained. The salt is genuine sea-salt, formed in brine-pans, chiefly in the Mediterranean104. As the water evaporated the Shrimps it contained gradually died; but the eggs in the females became encapsuled in the salt-crystals to hatch out long months after. In one of my own experiments I succeeded with salt that I had kept for more than a year. Of course, every sample of salt experimented with will not yield successful results, but failures are not expensive. Now in this brine-pan there were myriads of other animals which were killed outright105: the Brine Shrimp is at least able to pass on descendants by reason of the vitality106 of its eggs. Some near relations of the Brine Shrimps live in fresh water and possess similar powers of resistance to adverse107 conditions. The Fairy Shrimp (Chirocephalus) is one of these. Not unlike its cousin the Brine Shrimp in appearance, it lives in shallow pools, such as have muddy bottoms and are constantly liable to dry up. Birds hunting by the margins108 of the pool where the retreating water has left a fringe of mud bear away more or less of this on their feet and transport it to similar pools, or even puddles109. Such transplanted samples may easily contain numbers of eggs of this tiny creature. Only a year or 306two ago Fairy Shrimps were found in abundance in rain pools at Eton, and some, indeed, were discovered swimming gaily110 about in a rain-filled cart-rut!
Another very singular Crustacean111, known as Apus, bears a curious superficial likeness112 to the King Crab113 (Limulus), having a large back-shield and a long tail. This little creature, a giant compared with his nearest relations, is an inhabitant of wayside ponds and ditches. Thousands of females may be taken for years in succession without the advent59 of a single male. Then, for some strange reason which we cannot even guess at, males appear. Like its freshwater cousin, the Fairy Shrimp, Apus can withstand drought: its favourite haunts may be transformed into sun-baked hollows, but with a heavy fall of rain and a few hours’ soaking the eggs left by dead females develop, and once more the pool and its inhabitants are established again. Having regard to the extraordinary vitality of these small creatures, it is curious that they should ever disappear from their favoured haunts. But they do. Not many years ago Apus could be found in abundance in many parts of the South of England. It is now extinct; its last resorts were the ponds at Hampstead: now one may search in vain for them. “No British specimens115,” remarks Dr. Caiman, a great authority on the Crustacea, “had been recorded for over forty years, and the species was believed to be extinct in this country, when it was found in 1907 by Mr. F. Balfour Browne in a brackish116 marsh117 near Southwick, in Kirkcudbrightshire.” These had probably developed from eggs accidentally transported by some bird from the Continent. The extinction118 of the race throughout the British Islands can only be attributed to the too long absence of males, and the consequent307 inability to restore vigour119 by the more normal method of reproduction by sexual congress.
Among the Rotifers the little Wheel-animalcules exhibit an even greater vitality, for not only can their eggs withstand prolonged desiccation, but in some the body of the animal survives even harsher treatment. If specimens be enclosed within a chamber containing a little sand or moss120 the contents may be dried over sulphuric acid, or heated up to 200° F., or left to the neglected dust of years, and will yet revive if a little fresh water be added to the sand. Males are rare, and when they do occur are little more than animated121 receptacles for semen, for they are incapable of feeding, the gullet and digestive tract122 being reduced to a solid cord. A certain amount of nourishment123, however, may be absorbed through the delicate body wall.
The degeneration of the males in these parthenogenetic species irresistibly124 reminds one of the smile of the Cheshire cat; they grow smaller and smaller, and their functions less and less, till finally nothing is left. The “complemental125 males” discovered years ago by Darwin in the Barnacles well illustrate126 this process. In dissecting127 adult specimens of the stalked Barnacle (Scalpellum) he found, just inside the valves, in a pocket of the mantle128, a varying number of “complemental males,” tiny organisms which Mr. Geoffrey Smith describes as “little more than bags of spermatozoa,” and they apparently serve to fertilize the ripe ova of the larger animal—one cannot say of the female, for Scalpellum, like most of the Barnacles, is hermaphrodite. But it is believed that these complemental males are really arrested hermaphrodites. At any rate, if it so be noted129 that with some of the Barnacles, as with some other Crustacea, the larv? are males, but 308when adult life is attained female glands130 appear and hermaphroditism is established. Such hermaphrodites have the singular distinction of being males which have acquired female attributes, true females being unknown among them!
In one of the parasitic Crustacea (Chondracanthus) infesting131 the gills of Gurnard, Plaice, Skate and other fish, the adult female is about half an inch long, and very unlike a Crustacean in appearance; the male is an extremely minute maggot-like object—a few millimetres in length—and lives permanently132 attached to the belly133 of his mate just at the base of the egg masses. More remarkable still is the case of another nearly related parasitic species—Lernea—which becomes sexually mature in its childhood. The males perform their part and die; their mates arrive at maturity134 and settle down to a comfortable life as parasites135 on fish, reproducing without further mating.
That Parthenogenesis and Hermaphroditism are but specialized136 forms of reproduction, leading sooner or later to degeneration and extinction, there can be no doubt. They are, so to speak, failures in the evolution of sex, demonstrating in a very forcible fashion the impossibility of progress—as we understand it—where the sexual functions are thus combined.
To the differentiation137 of sex, resulting in separate male and female individuals, we must attribute the marvellous complexity138 of the pageant139 of life which confronts us to-day. The story of the Courtship of Animals is only one of an infinite number of incidents in this pageant, and one which is by no means easy of interpretation140.
In these pages an attempt has been made to show that this differentiation of sex has, throughout, been309 accompanied by, and largely moulded by, common instincts and behaviour, and this interpretation is only to be reached by a study of the phenomena141 in their simplest form among the lower grades of animal life. Colour and the various sexual differences in form have been allowed to dominate this investigation142 of the problem of sex, and have diverted attention from more profitable and fruitful channels.
The lower we descend60 in the scale of animal life the less convincing becomes the argument that the colour, ornament or armature of the males is the result of sexual selection in the older, Darwinian sense. The argument of Geddes and Thomson and others that the males are more “katabolic,” the females more “anabolic,” seems no less unsatisfactory, for in many cases the female is just as highly ornamented143 as the male, and in others she is considerably144 large. Further, in their less specialized species the sexes are almost or quite indistinguishable externally, and are sombrely clad, just as at the opposite extreme we find them equally ornamented and equally active.
We shall be nearer the truth if we regard these secondary sexual characters as expression points of germinal variations. Though we seem hopelessly ignorant as to the inciting145 cause of the variations, at least we seem to be able to lay a finger on the agents by which they are effected. And these are the hormones146 of the primary and secondary sexual glands, whose functions affect more than the merely sexual side of the organism. They profoundly affect the coloration of animals, giving rise on the one hand to purely147 ornamental148 “secondary sexual characters,” and on the other to changes of coloration which achieve the ends of protective resemblance310 colours, or of “warning coloration,” as circumstances may demand. There is nothing more remarkable in this than the control which the pituitary body exercises over stature, either when in a pathological condition, or when the controlling action of the other gland114 secretions149 is removed, as by castration.
Hitherto much has been made of trophic nerves, which control growth; but it is probable we have overlooked the still more important action of “trophic” glands, such as the thyroid. This apparently controls growth in many directions. Adaptations to environment which are effected by changes in bodily shape-as in the transformation of land-dwelling mammals into Seals and Whales—are probably largely controlled by these glands. Their activity is as great as their manifestation81 is varied.
Why their action should be more stimulating150 in the case of the male, why he should lead the way in all the new acquirements of the species, both in non-sexual as well as in sexual characters, is by no means plain. But the fact remains151 that this is so. Remove any one of these glands and the machinery of growth is thrown out of gear; it is not merely the secondary sexual characters which are affected152.
But these glands are concerned no less intimately with the behaviour of animals. This is most obvious in all that concerns sexual appetite as the preceding chapters have already shown. Having regard to the immense variety of animals concerned, this behaviour presents an underlying153 uniformity of expression which must not be lost sight of: and the same is no less true of what we may call the physical manifestations of these glandular154 activities.
THE END
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1
maternity
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| n.母性，母道，妇产科病房；adj.孕妇的，母性的 | |
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2
degenerate
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| v.退步，堕落；adj.退步的，堕落的；n.堕落者 | |
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3
virgin
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| n.处女，未婚女子；adj.未经使用的；未经开发的 | |
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4
faculty
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| n.才能；学院，系；(学院或系的)全体教学人员 | |
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5
intervention
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| n.介入，干涉，干预 | |
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6
miraculous
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| adj.像奇迹一样的，不可思议的 | |
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7
credulous
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| adj.轻信的，易信的 | |
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8
lapses
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| n.失误，过失( lapse的名词复数 )；小毛病；行为失检；偏离正道v.退步( lapse的第三人称单数 )；陷入；倒退；丧失 | |
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9
virtue
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| n.德行，美德；贞操；优点；功效，效力 | |
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10
profess
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| v.声称，冒称，以...为业，正式接受入教，表明信仰 | |
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11
nuptial
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| adj.婚姻的，婚礼的 | |
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12
myriads
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| n.无数，极大数量( myriad的名词复数 ) | |
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13
myriad
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| adj.无数的；n.无数，极大数量 | |
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14
shimmering
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| v.闪闪发光，发微光( shimmer的现在分词 ) | |
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15
attain
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| vt.达到，获得，完成 | |
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strenuously
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| adv.奋发地，费力地 | |
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17
sanctuary
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| n.圣所，圣堂，寺庙；禁猎区，保护区 | |
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18
accomplished
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| adj.有才艺的；有造诣的；达到了的 | |
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revel
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| vi.狂欢作乐，陶醉；n.作乐，狂欢 | |
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20
renounce
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| v.放弃；拒绝承认，宣布与…断绝关系 | |
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21
entirely
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| ad.全部地，完整地；完全地，彻底地 | |
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22
vows
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| 誓言( vow的名词复数 )； 郑重宣布，许愿 | |
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23
repentance
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| n.懊悔 | |
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24
parental
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| adj.父母的；父的；母的 | |
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liking
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| n.爱好；嗜好；喜欢 | |
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26
burrow
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| vt.挖掘(洞穴)；钻进；vi.挖洞；翻寻；n.地洞 | |
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chamber
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| n.房间，寝室；会议厅；议院；会所 | |
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burrowing
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| v.挖掘（洞穴），挖洞( burrow的现在分词 )；翻寻 | |
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29
ripen
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| vt.使成熟；vi.成熟 | |
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30
saliva
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| n.唾液，口水 | |
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31
transformation
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| n.变化；改造；转变 | |
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32
puny
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| adj.微不足道的，弱小的 | |
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stature
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| n.（高度）水平，（高度）境界，身高，身材 | |
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forth
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| adv.向前；向外，往外 | |
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exhausted
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| adj.极其疲惫的，精疲力尽的 | |
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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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37
monotonous
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| adj.单调的，一成不变的，使人厌倦的 | |
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regularity
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| n.规律性，规则性；匀称，整齐 | |
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39
prospect
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| n.前景，前途；景色，视野 | |
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40
drudgery
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| n.苦工，重活，单调乏味的工作 | |
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41
mere
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| adj.纯粹的；仅仅，只不过 | |
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42
fertilizing
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| v.施肥( fertilize的现在分词 ) | |
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43
perpetuate
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| v.使永存，使永记不忘 | |
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44
thraldom
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| n.奴隶的身份，奴役，束缚 | |
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45
appalling
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| adj.骇人听闻的，令人震惊的，可怕的 | |
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46
prolific
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| adj.丰富的，大量的；多产的，富有创造力的 | |
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47
prolificness
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| 挥霍 | |
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48
joyous
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| adj.充满快乐的；令人高兴的 | |
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49
deliriously
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| adv.谵妄（性）；发狂；极度兴奋/亢奋；说胡话 | |
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50
parasitic
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| adj.寄生的 | |
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51
fertilize
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| v.使受精，施肥于，使肥沃 | |
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52
wasps
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| 黄蜂( wasp的名词复数 )； 胡蜂； 易动怒的人； 刻毒的人 | |
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53
progeny
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| n.后代，子孙；结果 | |
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54
sporadically
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| adv.偶发地，零星地 | |
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55
apparently
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| adv.显然地；表面上，似乎 | |
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56
swarms
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| 蜂群，一大群( swarm的名词复数 ) | |
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57
functional
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| adj.为实用而设计的，具备功能的，起作用的 | |
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58
adventurous
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| adj.爱冒险的；惊心动魄的，惊险的，刺激的 | |
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59
advent
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| n.(重要事件等的)到来，来临 | |
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60
descend
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| vt./vi.传下来，下来，下降 | |
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61
astounding
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| adj.使人震惊的vt.使震惊，使大吃一惊astound的现在分词) | |
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62
fecundity
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| n.生产力；丰富 | |
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64
imbued
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| v.使（某人/某事）充满或激起（感情等）( imbue的过去式和过去分词 )；使充满；灌输；激发（强烈感情或品质等） | |
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65
dread
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| vt.担忧，忧虑；惧怕，不敢；n.担忧，畏惧 | |
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66
impending
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| a.imminent, about to come or happen | |
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67
avert
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| v.防止，避免；转移(目光、注意力等) | |
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68
calamity
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| n.灾害，祸患，不幸事件 | |
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69
remarkable
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| adj.显著的，异常的，非凡的，值得注意的 | |
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70
termite
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| n.白蚁 | |
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71
upwards
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| adv.向上，在更高处...以上 | |
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72
abdomen
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| n.腹，下腹(胸部到腿部的部分) | |
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73
attains
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| （通常经过努力）实现( attain的第三人称单数 )； 达到； 获得； 达到（某年龄、水平、状况） | |
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74
seclusion
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| n.隐遁，隔离 | |
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75
subterranean
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| adj.地下的，地表下的 | |
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76
spouse
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| n.配偶(指夫或妻) | |
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77
incapable
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| adj.无能力的，不能做某事的 | |
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78
ornament
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| v.装饰，美化；n.装饰，装饰物 | |
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79
machinery
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| n.(总称)机械，机器；机构 | |
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80
manifestations
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| n.表示，显示（manifestation的复数形式） | |
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81
manifestation
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| n.表现形式；表明；现象 | |
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82
hordes
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| n.移动着的一大群( horde的名词复数 )；部落 | |
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83
well-being
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| n.安康，安乐，幸福 | |
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84
exterminated
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| v.消灭，根绝( exterminate的过去式和过去分词 ) | |
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85
survivors
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| 幸存者，残存者，生还者( survivor的名词复数 ) | |
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86
contrived
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| adj.不自然的，做作的；虚构的 | |
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87
varied
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| adj.多样的，多变化的 | |
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88
facets
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| n.（宝石或首饰的）小平面( facet的名词复数 )；（事物的）面；方面 | |
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89
versatility
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| n.多才多艺，多样性，多功能 | |
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90
speculative
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| adj.思索性的，暝想性的，推理的 | |
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91
ingenuity
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| n.别出心裁；善于发明创造 | |
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92
niches
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| 壁龛( niche的名词复数 )； 合适的位置[工作等]； （产品的）商机； 生态位（一个生物所占据的生境的最小单位） | |
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93
peculiar
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| adj.古怪的，异常的；特殊的，特有的 | |
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94
advancement
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| n.前进，促进，提升 | |
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95
shrimp
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| n.虾，小虾；矮小的人 | |
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96
pints
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| n.品脱( pint的名词复数 )；一品脱啤酒 | |
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97
specks
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| n.眼镜；斑点，微粒，污点( speck的名词复数 ) | |
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98
shrimps
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| n.虾，小虾( shrimp的名词复数 )；矮小的人 | |
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99
consistency
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| n.一贯性，前后一致，稳定性；(液体的)浓度 | |
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100
translucent
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| adj.半透明的；透明的 | |
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101
downwards
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| adj./adv.向下的（地），下行的（地） | |
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102
rhythmical
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| adj.有节奏的，有韵律的 | |
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103
distinguished
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| adj.卓越的，杰出的，著名的 | |
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104
Mediterranean
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| adj.地中海的；地中海沿岸的 | |
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105
outright
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| adv.坦率地；彻底地；立即；adj.无疑的；彻底的 | |
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106
vitality
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| n.活力，生命力，效力 | |
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107
adverse
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| adj.不利的；有害的；敌对的，不友好的 | |
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108
margins
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| 边( margin的名词复数 )； 利润； 页边空白； 差数 | |
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109
puddles
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| n.水坑， （尤指道路上的）雨水坑( puddle的名词复数 ) | |
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110
gaily
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| adv.欢乐地，高兴地 | |
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111
crustacean
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| n.甲壳动物；adj.甲壳纲的 | |
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112
likeness
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| n.相像，相似（之处） | |
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113
crab
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| n.螃蟹，偏航，脾气乖戾的人，酸苹果；vi.捕蟹，偏航，发牢骚；vt.使偏航，发脾气 | |
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114
gland
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| n.腺体，(机)密封压盖，填料盖 | |
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115
specimens
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| n.样品( specimen的名词复数 )；范例；（化验的）抽样；某种类型的人 | |
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116
brackish
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| adj.混有盐的；咸的 | |
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117
marsh
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| n.沼泽，湿地 | |
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118
extinction
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| n.熄灭，消亡，消灭，灭绝，绝种 | |
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119
vigour
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| （=vigor）n.智力，体力，精力 | |
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120
moss
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| n.苔，藓，地衣 | |
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121
animated
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| adj.生气勃勃的，活跃的，愉快的 | |
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122
tract
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| n.传单，小册子，大片(土地或森林) | |
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123
nourishment
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| n.食物，营养品；营养情况 | |
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124
irresistibly
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| adv.无法抵抗地，不能自持地；极为诱惑人地 | |
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125
complemental
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| 补足的，补充的 | |
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126
illustrate
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| v.举例说明，阐明；图解，加插图 | |
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127
dissecting
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| v.解剖（动物等）( dissect的现在分词 )；仔细分析或研究 | |
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128
mantle
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| n.斗篷，覆罩之物，罩子；v.罩住，覆盖，脸红 | |
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129
noted
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| adj.著名的，知名的 | |
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130
glands
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| n.腺( gland的名词复数 ) | |
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131
infesting
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| v.害虫、野兽大批出没于( infest的现在分词 )；遍布于 | |
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132
permanently
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| adv.永恒地，永久地，固定不变地 | |
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133
belly
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| n.肚子，腹部；(像肚子一样)鼓起的部分，膛 | |
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134
maturity
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| n.成熟；完成；(支票、债券等)到期 | |
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135
parasites
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| 寄生物( parasite的名词复数 )； 靠他人为生的人； 诸虫 | |
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136
specialized
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| adj.专门的，专业化的 | |
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137
differentiation
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| n.区别，区分 | |
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138
complexity
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| n.复杂(性)，复杂的事物 | |
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139
pageant
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| n.壮观的游行；露天历史剧 | |
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140
interpretation
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| n.解释，说明，描述；艺术处理 | |
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141
phenomena
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| n.现象 | |
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142
investigation
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| n.调查，调查研究 | |
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143
ornamented
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| adj.花式字体的v.装饰，点缀，美化( ornament的过去式和过去分词 ) | |
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144
considerably
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| adv.极大地；相当大地；在很大程度上 | |
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145
inciting
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| 刺激的，煽动的 | |
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146
hormones
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| n. 荷尔蒙，激素 名词hormone的复数形式 | |
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147
purely
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| adv.纯粹地，完全地 | |
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148
ornamental
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| adj.装饰的；作装饰用的；n.装饰品；观赏植物 | |
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149
secretions
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| n.分泌（物）( secretion的名词复数 ) | |
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150
stimulating
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| adj.有启发性的，能激发人思考的 | |
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151
remains
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| n.剩余物，残留物；遗体，遗迹 | |
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152
affected
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| adj.不自然的，假装的 | |
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153
underlying
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| adj.在下面的，含蓄的，潜在的 | |
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154
glandular
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| adj.腺体的 | |
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