Evolution: Origins of Life
Chapter 6: Arguments Against the Theory
May 4, 2003
May 18, 2003
Section I: Arguments Against Evolution
The evidence, or reasons why I believe in the theory of Evolution, have been presented in the earlier chapters. This sole chapter is dedicated to answering arguments often presented against the Theory of Evolution. Though often not an argument against the theory of Natural Selection or Evolution, it is often wondered how the consciousness of an animal changes to adapt to its new body variations. I will here quote an excerpt of Darwin...
Of cases of changed habits it will suffice merely to allude to that of the many British insects which now feed on exotic plants, or exclusively on artificial substances. Of diversified habits innumerable instances could be given: I have often watched a tyrant flycatcher (Saurophagus sulphuratus) in South America, hovering over one spot and then proceeding to another, like a kestrel, and at other times standing stationary on the margin of water, and then dashing into it like a kingfisher at a fish. In our own country the larger titmouse (Parus major) may be seen climbing branches, almost like a creeper; it sometimes, like a shrike, kills small birds by blows on the head; and I have many times seen and heard it hammering the seeds of the yew on a branch, and thus breaking them like a nuthatch. In North America the black bear was seen by Hearne swimming for hours with widely open mouth, thus catching, almost like a whale, insects in the water.
As we sometimes see individuals following habits different from those proper to their species and to the other species of the same genus, we might expect that such individuals would occasionally give rise to new species, having anomalous habits, and with their structure either slightly or considerably modified from that of their type. And such instances occur in nature. Can a more striking instance of adaptation be given than that of a woodpecker for climbing trees and seizing insects in the chinks of the bark? Yet in North America there are woodpeckers which feed largely on fruit, and others with elongated wings which chase insects on the wing. On the plains of La Plata, where hardly a tree grows, there is a woodpecker (Colaptes campestris) which has two toes before and two behind, a long pointed tongue, pointed tail-feathers, sufficiently stiff to support the bird in a vertical position on a post, but not so stiff as in the typical woodpeckers, and a straight strong beak. The beak, however, is not so straight or so strong as in the typical woodpeckers, but it is strong enough to bore into wood. Hence this Colaptes in all the essential parts of its structure is a woodpecker. Even in such trifling characters as the colouring, the harsh tone of the voice, and undulatory flight, its close blood-relationship to our common woodpecker is plainly declared; yet, as I can assert, not only from my own observation, but from those of the accurate Azara, in certain large districts it does not climb trees, and it makes its nest in holes in banks! In certain other districts, however, this same woodpecker, as Mr. Hudson states, frequents trees, and bores holes in the trunk for its nest. I may mention as another illustration of the varied habits of this genus, that a Mexican Colaptes has been described by De Saussure as boring holes into hard wood in order to lay up a store of acorns.
Petrels are the most aerial and oceanic of birds, but in the quiet sounds of Tierra del Fuego, the Puffinuria berardi, in its general habits, in its astonishing power of diving, in its manner of swimming and of flying when made to take flight, would be mistaken by any one for an auk or a grebe; nevertheless it is essentially a petrel, but with many parts of its organisation profoundly modified in relation to its new habits of life; whereas the woodpecker of La Plata has had its structure only slightly modified. In the case of the waterouzel, the acutest observer by examining its dead body would never have suspected its subaquatic habits; yet this bird, which is allied to the thrush family, subsists by diving- using its wings under water, and grasping stones with its feet. All the members of the great order of hymenopterous insects are terrestrial excepting the genus Proctotrupes, which Sir John Lubbock has discovered to be aquatic in its habits; it often enters the water and dives about by the use not of its legs but of its wings, and remains as long as four hours beneath the surface; yet it exhibits no modification in structure in accordance with its abnormal habits. [*1]
Though Natural Selection is hardly doubted, even by those who confess to believe in a theory opposite of Evolution, there are still some to oppose it, and argue that Natural Selection is fictitious, because nature cannot choose anything, as it is not a sentient being. However, when we speak of nature, understand that I am only speaking of the laws that govern physical matter, the rules that man has defined to help him understand the Universe better. So, when we speak of Natural Selection, we are speaking of how the laws that govern our Universe eventually result with one creature, or organism, reigning supreme over another, thus, surviving and reproducing. [*2]
One common argument against Evolution is, if organisms tend to rise and advance in organization through the means of Natural Selection, and thus become more adapted to their environment, why are there numerous creatures inhabiting all the niches of the ecological system? For instance, there are microscopic bacteria organisms. While they are small and occupy a small space, one may wonder why, through the means of Natural Selection, they do not rise and become more advanced and organized? The answer is as simple as this: though there are organisms of every level of organization, the reason for the existence of lower level creatures is due to the fact that, in their ecological niche, they are simple enough to gather enough energy, reproduce, and survive. If bacteria were to evolve into something as complex as a mammal, over the course of hundreds of millions of years, it would have been in vain if there was no food for the mammal to eat. Hence, we can see why humans have not advanced to the point where we are twenty or thirty feet tall -- while it would be an ecological advantage, it would require us to eat massive amounts of food, unlike our current selves. The reason why microscopic bacteria is not leaving its current place, though it may evolve into other organisms that will fill other places where food is available, the reason for this is because they currently have enough food in their current place to survive and reproduce, which is enough for any organism to live. [*3]
Another hypothetical consideration for the idea of Natural Selection is, if Natural Selection is reasonable, then would it not create an indefinite number of species, or why has it not done this? The simple reply to this is easy. Once an organism fills a place in nature where it can survive and reproduce, the following generations will only be adapted better to this current place in nature. There is not an indefinite amount of places where food can be obtained, so there will not be an indefinite amount of species surviving and reproducing. [*4] One may argue that the unique and advanced nature of the eye, for instance, is by far too complex on organ for Natural Selection to create. To quote Charles Darwin...
To suppose that the eye with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, seems, I freely confess, absurd in the highest degree. When it was first said that the sun stood still and the world turned round, the common sense of mankind declared the doctrine false; but the old saying of Vox populi, vox Dei, as every philosopher knows, cannot be trusted in science. Reason tells me, that if numerous gradations from a simple and imperfect eye to one complex and perfect can be shown to exist, each grade being useful to its possessor, as is certainly the case; if further, the eye ever varies and the variations be inherited, as is likewise certainly the case and if such variations should be useful to any animal under changing conditions of life, then the difficulty of believing that a perfect and complex eye could be formed by natural selection, though insuperable by our imagination, should not be considered as subversive of the theory. How a nerve comes to be sensitive to light, hardly concerns us more than how life itself originated; but I may remark that, as some of the lowest organisms, in which nerves cannot be detected, are capable of perceiving light, it does not seem impossible that certain sensitive elements in their sarcode should become aggregated and developed into nerves, endowed with this special sensibility.
In searching for the gradations through which an orgain in any species has been perfected, we ought to look exclusively to its lineal progenitors; but this is scarcely ever possible, and we are forced to look to other species and genera of the same group, that is to the collateral descendants from the same parent-form, in order to see what gradations are possible, and for the chance of some gradations having been transmitted in an unaltered or little altered condition. But the state of the same organ in distinct classes may incidentally throw light on the steps by which it has been perfected.
The simplest organ which can be called an eye consists of an optic nerve, surrounded by pigment-cells, and covered by translucent skin, but without any lens or other refractive body. We may, however, according to M. Jourdain, descend even a step lower and find aggregates of pigment-cells, apparently serving as organs of vision, without any nerves, and resting merely on sarcodic tissue. Eyes of the above simple nature are not capable of distinct vision, and serve only to distinguish light from darkness. In certain star-fishes, small depressions in the layer of pigment which surrounds the nerve are filled, as described by the author just quoted, with transparent gelatinous matter, projecting with a convex surface, like the cornea in the higher animals. He suggests that this serves not to form an image, but only to concentrate the luminous rays and render their perception more easy. In this concentration of the rays we gain the first and by far the most important step towards the formation of a true, picture-forming eye; for we have only to place the naked extremity of the optic nerve, which in some of the lower animals lies deeply buried in the body, and in some near the surface, at the right distance from the concentrating apparatus, and an image will be formed on it.
In the great class of the Articulata, we may start from an optic nerve simply coated with pigment, the latter sometimes forming a sort of pupil, but destitute of a lens or other optical contrivance. With insects it is now known that the numerous facets on the cornea of their great compound eyes form true lenses, and that the cones include curiously modified nervous filaments. But these organs in the Articulata are so much diversified that Muller formerly made three main classes with seven subdivisions, besides a fourth main class of aggregated simple eyes.
When we reflect on these facts, here given much too briefly, with respect to the wide, diversified, and graduated range of structure in the eyes of the lower animals; and when we bear in mind how small the number of all living forms must be in comparison with those which have become extinct, the difficulty ceases to be very great in believing that natural selection may have converted the simple apparatus of an optic nerve, coated with pigment and invested by transparent membrane, into an optical instrument as perfect as is possessed by any member of the articulate class.
He who will go thus far, ought not to hesitate to go one step further, if he finds on finishing this volume that large bodies of facts, otherwise inexplicable, can be explained by the theory of modification through natural selection; he ought to admit that a structure even as perfect as an eagle's eye might thus be formed, although in this case he does not know the transitional states. It has been objected that in order to modify the eye and still preserve it as a perfect instrument, many changes would have to be effected simultaneously, which, it is assumed, could not be done through natural selection; but as I have attempted to show in my work on the variation of domestic animals, it is not necessary to suppose that the modifications were all simultaneous, if they were extremely slight and gradual. Different kinds of modification would, also, serve for the same general purpose: as Mr. Wallace has remarked, "if a lens has too short or too long a focus, it may be amended either by an alteration of curvature, or an alteration of density; if the curvature be irregular, and the rays do not converge to a point, then any increased regularity of curvature will be an improvement. So the contraction of the iris and the muscular movements of the eye are neither of them essential to vision, but only improvements which might have been added and perfected at any stage of the construction of the instrument." Within the highest division of the animal kingdom, namely, the Vertebrata, we can start from an eye so simple, that it consists, as in the lancelet, of a little sack of transparent skin, furnished with a nerve and lined with pigment, but destitute of any other apparatus. In fishes and reptiles, as Owen has remarked, "the range of gradations of dioptric structures is very great." It is a significant fact that even in man, according to the high authority of Virchow, the beautiful crystalline lens is formed in the embryo by an accumulation of epidermic cells, lying in a sack-like fold of the skin; and the vitreous body is formed from embryonic sub-cutaneous tissue. To arrive, however, at a just conclusion regarding the formation of the eye, with all its marvellous yet not absolutely perfect characters, it is indispensable that the reason should conquer the imagination; but I have felt the difficulty far too keenly to be surprised at others hesitating to extend the principle of natural selection to so startling a length.
It is scarcely possible to avoid comparing the eye with a telescope. We know that this instrument has been perfected by the long-continued efforts of the highest human intellects; and we naturally infer that the eye has been formed by a somewhat analogous process. But may not this inference be presumptuous? Have we any right to assume that the Creator works by intellectual powers like those of man? If we must compare the eye to an optical instrument, we ought in imagination to take a thick layer of transparent tissue, with spaces filled with fluid, and with a nerve sensitive to light beneath, and then suppose every part of this layer to be continually changing slowly in density, so as to separate into layers of different densities and thicknesses, placed at different distances from each other, and with the surfaces of each layer slowly changing in form. Further we must suppose that there is a power, represented by natural selection or the survival of the fittest, always intently watching each slight alteration in the transparent layers; and carefully preserving each which, under varied circumstances, in any way or in any degree, tends to produce a distincter image. We must suppose each new state of the instrument to be multiplied by the million; each to be preserved until a better one is produced, and then the old ones to be all destroyed. In living bodies, variation will cause the slight alterations, generation will multiply them almost infinitely, and natural selection will pick out with unerring skill each improvement. Let this process go on for millions of years; and during each year on millions of individuals of many kinds; and may we not believe that a living optical instrument might thus be formed as superior to one of glass, as the works of the Creator are to those of man? [*5]
The theory of Evolution is greatly supported from the method by which naturalists organize life, into different kingdoms, then phylums, then different orders, families, species, and races, until we are capable of distinguishing the amount of difference between different organisms. We notice, however, that there are some creatures of completely different phylums or kingdoms, and yet they have developed similar organs. For instance, the electric eel is capable of producing electricity, much like the sting ray has a mechanism for producing a small amount of electricity. Organisms of extreme distance in relation will inevitably produce organs which suffice to the same function as each other. The case is analogous to two inventors in different countries, working on the same invention to solve the same problem. But like the inventors, the organs which resemble each other in different organisms, though they serve the same purpose, they are intrinsically built in completely different methods from each other, whereas the construction of the tissue around the os coccyx of the human is similar to that of the tails on other tailed creatures. [*6] What, though, may be said of the absence or rarity of transitional forms, or linking organisms, such as the one which links mankind to primates? Quoting Darwin...
The intermediate variety, consequently, will exist in lesser numbers from inhabiting a narrow and lesser area; and practically, as far as I can make out, this rule holds good with varieties in a state of nature. I have met with striking instances of the rule in the case of varieties intermediate between well-marked varieties in the genus Balanus. And it would appear from information given me by Mr. Watson, Dr. Asa Gray, and Mr. Wollaston, that generally, when varieties intermediate between two other forms occur, they are much rarer numerically than the forms which they connect. Now, if we may trust these facts and inferences, and conclude that varieties linking two other varieties together generally have existed in lesser numbers than the forms which they connect, then we can understand why intermediate varieties should not endure for very long periods:- why, as a general rule, they should be exterminated and disappear, sooner than the forms which they originally linked together.
For forms existing in larger numbers will have a better chance, within any given period, of presenting further favourable variations for natural selection to seize on, than will the rarer forms which exist in lesser numbers. Hence, the more common forms, in the race for life, will tend to beat and supplant the less common forms, for these will be more slowly modified and improved. It is the same principle which, as I believe, accounts for the common species in each country, as shown in the second chapter, presenting on an average a greater number of well-marked varieties than do the rarer species.
To sum up, I believe that species come to be tolerably well-defined objects, and do not at any one period present an inextricable chaos of varying and intermediate links; first, because new varieties are very slowly formed, for variation is a slow process, and natural selection can do nothing until favourable individual differences or variations occur, and until a place in the natural polity of the country can be better filled by some modification of some one or more of its inhabitants. And such new places will depend on slow changes of climate, or on the occasional immigration of new inhabitants, and, probably, in a still more important degree, on some of the old inhabitants becoming slowly modified, with the new forms thus produced, and the old ones acting and reacting on each other. So that, in any one region and at any one time, we ought to see only a few species presenting slight modifications of structure in some degree permanent; and this assuredly we do see.
...when two or more varieties have been formed in different portions of a strictly continuous area, intermediate varieties will, it is probable, at first have been formed in the intermediate zones, but they will generally have had a short duration. For these intermediate varieties will, from reasons already assigned (namely from what we know of the actual distribution of closely allied or representative species, and likewise of acknowledged varieties), exist in the intermediate zones in lesser numbers than the varieties which they tend to connect. From this cause alone the intermediate varieties will be liable to accidental extermination; and during the process of further modification through natural selection, they will almost certainly be beaten and supplanted by the forms which they connect; for these from existing in greater numbers will, in the aggregate, present more varieties, and thus be further improved through natural selection and gain further advantages.
When we see any structure highly perfected for any particular habit, as the wings of a bird for flight, we should bear in mind that animals displaying early transitional grades of the structure will seldom have survived to the present day, for they will have been supplanted by their successors, which were gradually rendered more perfect through natural selection. [*7]
Some will claim that nature's so-called "vestigial organs" are not vestigial at all, but rather are created for the beauty of mankind. The first point I will respond to this argument is the question of beauty. Even in different nations of mankind, the definition of "beautiful" and "ugly" varies greatly, ignoring altogether that one person's concept of these ideas may vary greatly from another, even if the two are related. In regard to the appendix of the human, how is it that it may inspire beauty? For millions of years, it had not been observed, and even today it is embedded inside our bodies. When removed, there is nothing particularly extraordinary about it. There are also vestigial muscles. By what writ can anyone claim that they are beautiful? They are attached to the os coccyx, and in instances of reversion, sometimes in the back of the neck or other random parts, but how might they incite beauty? Simply put, this argument that vestigial organs are created for beauty is ignorant. [*8]
Also, there is the question of why a bee has evolved in the way that it is -- that the proper usage of its sting will actually kill the creature. If organisms evolve and change through Natural Selection so that they can survive and reproduce, why is it that the mechanisms of the bee lead it to suicide? However, in this case, we see that Natural Selection has risen to an more advanced form. Those bee colonies that did not have suicidal stingers, for instance, perished, because none were capable of fending off invaders. Yet, those bee colonies that had suicidal stingers, and successfully fended off invaders, did survive, and were capable of reproducing. So we see here, Natural Selection is not a system of survival simply with one organism versus another organism, but it can be raised even higher, to one society versus another society. In human terms, this is also observable: humans are kindly and even charitable to one another in some instances, without personal gain. [*9] Finally, there is one real argument against Evolution and Natural Selection that stands: how is it that such small advantages in an organism be so important to its survival? On that question, I will end with a quote by the father of Natural Selection...
The tail of the giraffe looks like an artificially constructed fly-flapper; and it seems at first incredible that this could have been adapted for its present purpose by successive slight modifications, each better and better fitted, for so trifling an object as to drive away flies; yet we should pause before being too positive even in this case, for we know that the distribution and existence of cattle and other animals in South America absolutely depend on their power of resisting the attacks of insects: so that individuals which could by any means defend themselves from these small enemies, would be able to range into new pastures and thus gain a great advantage. It is not that the larger quadrupeds are actually destroyed (except in some rare cases) by flies, but they are incessantly harassed and their strength reduced, so that they are more subject to disease, or not so well enabled in a coming dearth to search for food, or to escape from beasts of prey. [*10]
*1. Origin of the Species, by Charles Darwin, 1859, Sixth Edition, chapter 6.
*2. Origin of the Species, by Charles Darwin, 1859, Sixth Edition, chapter 4.
*3. Origin of the Species, by Charles Darwin, 1859, Sixth Edition, chapter 4.
*4. Origin of the Species, by Charles Darwin, 1859, Sixth Edition, chapter 4.
*5. Origin of the Species, by Charles Darwin, 1859, Sixth Edition, chapter 6.
*6. Origin of the Species, by Charles Darwin, 1859, Sixth Edition, chapter 6.
*7. Origin of the Species, by Charles Darwin, 1859, Sixth Edition, chapter 6.
*8. Origin of the Species, by Charles Darwin, 1859, Sixth Edition, chapter 6.
*9. Origin of the Species, by Charles Darwin, 1859, Sixth Edition, chapter 6.
*10. Origin of the Species, by Charles Darwin, 1859, Sixth Edition, chapter 6.