The Theory of Evolution

... Animals may have originated more than once, in different places and at different times ...
Harry Whittington (1985)

"In the broadest sense, evolution is merely change, and so is all-pervasive; galaxies, languages, and political systems all evolve. Biological evolution ... is change in the properties of populations of organisms that transcend the lifetime of a single individual. The ontogeny of an individual is not considered evolution; individual organisms do not evolve. The changes in populations that are considered evolutionary are those that are inheritable via the genetic material from one generation to the next. Biological evolution may be slight or substantial; it embraces everything from slight changes in the proportion of different alleles within a population (such as those determining blood types) to the successive alterations that led from the earliest protoorganism to snails, bees, giraffes, and dandelions."

- Douglas J. Futuyma in Evolutionary Biology, Sinauer Associates 1986

Charles Darwin considered eyes a formidable challenge to his theory of natural selection. "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 possible 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."  On the Origin of Species, Charles Darwin.

     Theodosius Dobzhansky (1900-1975)

Theodosius Dobzhansky was one of the architects of the so called Evolutionary Synthesis or Synthetic Theory of Evolution, a movement for unifying the biological sciences that was held in late twenties until beginnings of the 1940 decade. Apart from his outstanding contribution to the development of the genetics and evolution of natural populations, Dobzhansky played an influential role in the establishment of research groups in some South American countries, mainly in Brazil (secondarily in Chile and Colombia). The present paper describes part of his life since his Russian roots, going to Thomas Hunt Morgan's laboratory and his activities in Brazil during four long terms: 1943 (four months), 1948 (one year), 1952 (three months) and 1955 (one year). A brief analysis is made about the main objectives of the researches in Brazil as well as about the personal interactions with his Brazilian fellows and the consequences for the development of genetics in this country.

"Imagine if we were to try to spell out the 23 letters and spaces in the phrase "THE THEORY OF EVOLUTION" by using the evolutionary principle of chance. We might proceed by randomly drawing characters from a Scrabble set consisting of the 26 letters of the alphabet plus a space (for a total of 27). The probability of getting any particular letter or space in our phrase using this method would be one chance out of 27 (expressed as 1/27). The probability of getting all 23 letters and spaces in the order required for our phrase can be calculated by multiplying together the probability of getting each letter and space (1/27 x 1/27 x 1/27 -- for a total of 23 times). This calculation reveals that we could expect to succeed in correctly spelling our phrase by chance, approximately once in eight hundred, million, trillion, trillion draws! If we were to hurry the process along and draw our letters at the rate of a billion per second, we could expect to spell our simple little phrase once in 26 thousand, trillion years! But even this is a "virtual certainty" compared to the probability of correctly assembling any one of the known biological proteins by chance!

The 500 amino acids that make up an average-sized protein can be arranged in over 1 x 10^600 different ways (that's the number ONE followed by 600 zeros)! This number is vastly larger than the total number of atomic particles that could be packed into the known universe. If we had a computer that could rearrange the 500 amino acids of a particular protein at the rate of a billion combinations a second, we would stand essentially no chance of hitting the correct combination during the 14 billion years evolutionists claim for the age of the universe. Even if our high-speed computer were reduced to the size of an electron and we had enough of them to fill a room measuring 10 billion light years square (about 1 x 10^150 computers!), they would still be exceedingly unlikely to hit the right combination. Such a "room" full of computers could only rearrange about 1 x 10^180 combinations in 300 billion years. In fact, even if all the proteins that ever existed on earth were all different, our "room" full of computers would be exceedingly unlikely to chance upon the combination of any one of them in a mere 300 billion years!"
- David N. Menton, Ph.D

"As an organ developed via the opportunistic twists and turns of evolutionary processes, the human eye is explainable. As an organ designed and created by an infinitely wise deity, the human eye is inexcusable. For unlike the invertebrate eyes ..., the human eye is constructed upon the foundation of an almost incredible error: The retina has been put together backwards! Unlike the retinas of octopuses and squids, in which the light-gathering cells are aimed forward, toward the source of incoming light, the photoreceptor cells (the so called rods and cones) of the human retina are aimed backward, away from the light source. Worse yet, the nerve fibers which must carry signals from the retina to the brain must pass in front of the receptor cells, partially impeding the penetration of light to the receptors. Only a blasphemer would attribute such a situation to divine design!

Although the human eye would be a scandal if it were the result of divine deliberation, a plausible evolutionary explanation of its absurd construction can be obtained quite easily--even though we can make little use of paleontology (because eyes, like all soft tissues, rarely fossilize)."
- Frank Zindler

Terms Used in Describing the Nature of Science

Fact: In science, an observation that has been repeatedly confirmed and for all practical purposes is accepted as "true." Truth in science, however, is never final, and what is accepted as a fact today may be modified or even discarded tomorrow.

Hypothesis: A tentative statement about the natural world leading to deductions that can be tested. If the deductions are verified, the hypothesis is provisionally corroborated. If the deductions are incorrect, the original hypothesis is proved false and must be abandoned or modified. Hypotheses can be used to build more complex inferences and explanations.

Law: A descriptive generalization about how some aspect of the natural world behaves under stated circumstances.

Theory: In science, a well- substantiated explanation of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypotheses.

The contention that evolution should be taught as a "theory, not as a fact" confuses the common use of these words with the scientific use. In science, theories do not turn into facts through the accumulation of evidence. Rather, theories are the end points of science. They are understandings that develop from extensive observation, experimentation, and creative reflection. They incorporate a large body of scientific facts, laws, tested hypotheses, and logical inferences. In this sense, evolution is one of the strongest and most useful scientific theories we have.

        Erasmus Darwin (1731-1802)

Charles Darwin's grandfather, Erasmus Darwin, was one of the leading intellectuals of eighteenth century England, a man with a remarkable array of interests and pursuits. Erasmus Darwin was a respected physician, a well known poet, philosopher, botanist, and naturalist.

As a naturalist, he formulated one of the first formal theories on evolution in Zoonomia, or, The Laws of Organic Life (1794-1796). He also presented his evolutionary ideas in verse, in particular in the posthumously published poem The Temple of Nature. Although he did not come up with natural selection, he did discuss ideas that his grandson elaborated on sixty years later, such as how life evolved from a single common ancestor, forming "one living filament". He wrestled with the question of how one species could evolve into another. Although some of his ideas on how evolution might occur are quite close to those of Lamarck, Erasmus Darwin also talked about how competition and sexual selection could cause changes in species: "The final course of this contest among males seems to be, that the strongest and most active animal should propogate the species which should thus be improved". Erasmus Darwin arrived at his conclusions through an "integrative" approach: he used his observations of domesticated animals, the behaviour of wildlife, and he integrated his vast knowledge of many different fields, such as paleontology, biogeography, systematics, embryology, and comparative anatomy. This "integrative" approach is the very foundation upon which the U.C. Museum of Paleontology and the recently formed Integrative Biology Department at the University of California at Berkeley are built.

In addition to Erasmus Darwin's contributions to the future of biological studies, he was also a leader in an intellectual community that contributed to the emergence of the industrial era. Among his intellectual peers were James Watt, Matthew Boulton, Joseph Priestly, and Josiah Wedgwood. It is probably no coincidence that Charles Darwin, the grandson of such a progressive thinker, produced some of the most important work in the history of biological and social thought.

Organic life beneath the shoreless waves
Was born and nurs'd in ocean's pearly caves;
First forms minute, unseen by spheric glass,
Move on the mud, or pierce the watery mass;
These, as successive generations bloom,
New powers acquire and larger limbs assume;
Whence countless groups of vegetation spring,
And breathing realms of fin and feet and wing.

Erasmus Darwin. The Temple of Nature. 1802.

Introduction to Evolutionary Biology

Evolution Glossary

Julian Huxley

Darwin's "evolutionary and comprehensive vision" is a monistic one, it shows that our universe is a "unitary and continuous process," there does not exist a "dualistic split," and that all phenomena are natural. Darwin's idea, it is written,

"is the most powerful and the most comprehensive idea that has ever arisen on earth. It helps us understands our origins ... We are part of a total process, made of the same matter and operating by the same energy as the rest of the cosmos, maintaining and reproducing by the same type of mechanism as the rest of life ..."7 (Sir Julian Huxley.)

This quote of Julian Huxley's comes from his work, Evolutionary Humanism (Buffalo, N.Y.: Prometheus, 1992.) Julian Huxley was the grandson of Thomas H. Huxley (1825-1895). Thomas H. Huxley was an English biologist, teacher, and a defender of Darwin. Darwin was not a conversationalist and he only very rarely appeared in public to defend his theories himself; he was fully represented by Thomas H. Huxley, "Darwin's Bulldog." It is interesting to note what Thomas H. Huxley said about his topic when confronted with the opposition in the form of Bishop Wilberforce of Oxford. Both Huxley and Bishop Wilberforce were on the same stage when during a conference which had as its theme, Darwinism. The Bishop, in a sarcastic manner called out: "I would like to ask Professor Huxley whether it was on his grandfather's or his grandmother's side that the ape ancestry comes in." Darwin after whispering to his dinner companion, "The lord hath delivered him into my hands," took the podium:
"A man has no reason to be ashamed of having an ape for his grandfather. If there were an ancestor whom I should feel shame in recalling, it would be a man of restless and versatile intellect, who, not content with success in his own sphere of activity, plunges into scientific questions with which he has no real acquaintance, only to obscure them by an aimless rhetoric, and distract the attention of his hearers from the point at issue by eloquent digressions and skilled appeals to religious prejudice."

"...even if we accept that life came to Earth from outer space, we are still left with the problem of how it originated. I shall, therefore, assume that life was born right where it actually is: here on Earth"
-- Christian de Duve

Nor is anything gained by running the difficulty farther back.... Our going back, ever so far, brings us no nearer to the least degree of satisfaction upon the subject.
-- William Paley

"So we now have to talk about what we mean by disorder and what we mean by order. ... Suppose we divide the space into little volume elements. If we have black and white molecules, how many ways could we distribute them among the volume elements so that white is on one side and black is on the other? On the other hand, how many ways could we distribute them with no restriction on which goes where? Clearly, there are many more ways to arrange them in the latter case. We measure "disorder" by the number of ways that the insides can be arranged, so that from the outside it looks the same. The logarithm of that number of ways is the entropy. The number of ways in the separated case is less, so the entropy is less, or the "disorder" is less."
- Richard Feynmann

"When asked to provide evidence of long-term evolution, most scientists turn to the fossil record. Within this context, fossil horses are among the most frequently cited examples of evolution. The prominent Finnish paleontologist Bjorn Kurten wrote: 'One's mind inevitably turns to that inexhaustible textbook example, the horse sequence. This has been cited -- incorrectly more often than not -- as evidence for practically every evolutionary principle that has ever been coined.' This cautionary note notwith- standing, fossil horses do indeed provide compelling evidence in support of evolutionary theory."
- B. J. MacFadden

" ... The robustness of pattern generation and its capacity to change seem to be related properties. In tracing the evolutionary modification of the body plans of the major phyla we see the importance of adapting to the reproductive modifications of the egg. Finally, we see that many of the same multicellular and cellular mechanisms employed in early development are reapplied in the modifications of the body plan, in the head, and the appendages. We are left with the strong impression that evolution shapes the mechanisms of cell biology just as cell biology shapes the responses of organisms to selection. Evolutionary mechanisms and cellular mechanisms are intertwined; each is necessary for the other and the study of one enriches the study of the other. ..."

John Gerhart & Marc Kirschner - Cells, Embryos, and Evolution

Ontogeny Recapitulates Phylogeny ... ?

"The evolutionist is a detective who arrives on the scene a very long time after the events of interest have occurred. There are no witnesses, no answers written, just clues. There is the fossil record in the rocks from which it is possible to establish the chronological sequence of life-forms from the pre-Cambrian era to the present day. There are likenesses in form and anatomy among succeeding and contemporaneous organisms that suggest evolutionary divergence or convergence. There are DNA sequence comparisons that reveal in great detail similarities and divergences in the genetic make-up of organisms.

Other clues include the embryological ones that Haeckel referred to. Fish, reptiles and mammals look very different in their adult forms. During early development, however, there are many similarities. By studying embryonic development, one easily sees what Haeckel's rather short but to the point quote is stating."

Richard Bassetti

"Haeckel's drawings of 1874 (2) are substantially fabricated. In support of this view, I note that his oldest "fish" image is made up of bits and pieces from different animals--some of them mythical. It is not unreasonable to characterize this as "faking."

Later editions of Haeckel's drawings were somewhat more accurate, and showed significant variations among embryos of different species. Sadly, it is the discredited 1874 drawing that are used in so many British and American biology textbooks today."

Michael K. Richardson

"Evolution has no long-term goal. There is no long-distance target, no final perfection to serve as a criterion for selection, although human vanity cherishes the absurd notion that our species is the final goal of evolution."

"Cairns-Smith believes that the original life on this planet was based on self-replicating inorganic crystals such as silicates. If this is true, organic replicators, and eventually DNA, must later have taken over or usurped the role."

"Just as our eyes can see only that narrow band of electromagnetic frequencies that natural selection equipped our ancestors to see, so our brains are built to cope with narrow bands of sizes and times."

"The world becomes full of organisms that have what it takes to become ancestors. That, in a sentence, is Darwinism."

"The genetic code is not a binary code as in computers, nor an eight-level code as in some telephone systems, but a quaternary code with four symbols. The machine code of the genes is uncannily computerlike."

"There is no spirit-driven life force, no throbbing, heaving, pullulating, protoplasmic, mystic jelly. Life is just bytes and bytes and bytes or digital information."

"We - and that means all living things - are survival machines programmed to propagate the digital database that did the programming."

- Richard Dawkins  

The Informational Origin Of Feathers: An Overview

"Let me try to make crystal clear what is established beyond reasonable doubt, and what needs further study, about evolution. Evolution as a process that has always gone on in the history of the earth can be doubted only by those who are ignorant of the evidence or are resistant to evidence, owing to emotional blocks or to plain bigotry. By contrast, the mechanisms that bring evolution about certainly need study and clarification. There are no alternatives to evolution as history that can withstand critical examination. Yet we are constantly learning new and important facts about evolutionary mechanisms."

- Theodosius Dobzhansky "Nothing in Biology Makes Sense Except in the Light of Evolution", American Biology Teacher vol.35 (March 1973) reprinted in Evolution versus Creationism, J. Peter Zetterberg ed., ORYX Press, Phoenix AZ 1983

"The affinities of all the beings of the same class have sometimes been represented by a great tree. I believe this simile largely speaks the truth. The green and budding twigs may represent existing species; and those produced during each former year may represent the long succession of extinct species... The limbs divided into great branches, and these into lesser and lesser branches, were themselves once, when the tree was small, budding twigs; and this connexion of the former and present buds by ramifying branches may well represent the classification of all extinct and living species in groups subordinate to groups... From the first growth of the tree, many a limb and branch has decayed and dropped off, and these lost branches of various sizes may represent those whole orders, families, and genera which have now no living representatives, and which are known to us only from having been found in a fossil state... As buds give rise by growth to fresh buds, and these, if vigorous, branch out and overtop on all a feebler branch, so by generation I believe it has been with the great Tree of Life, which fills with its dead and broken branches the crust of the earth, and covers the surface with its ever branching and beautiful ramifications" (Charles Darwin, 1859).

"While today's digital hardware is extremely impressive, it is clear that the human retina's real-time performance goes unchallenged. Actually, to simulate 10 milliseconds (one hundredth of a second) of the complete processing of even a single nerve cell from the retina would require the solution of about 500 simultaneous nonlinear differential equations 100 times and would take at least several minutes of processing time on a Cray supercomputer. Keeping in mind that there are 10 million or more such cells interacting with each other in complex ways, it would take a minimum of 100 years of Cray time to simulate what takes place in your eye many times every second."

    Richard Dawkins

"And isn't it an arresting thought? We are digital archives of the African Pliocene, even of Devonian seas; walking repositories of wisdom out of the old days. You could spend a lifetime reading in this ancient library and die unsated by the wonder of it." Unweaving the Rainbow - Richard Dawkins

  Charles Darwin    (1809-82)

Charles Darwin was born in Shrewsbury, Shropshire. He was the son of Robert Waring Darwin and his wife Susannah, the grandson of the scientist Erasmus Darwin and of the potter Josiah Wedgwood. His mother died when he was eight years old and he was brought up by his sister. He was taught classics at Shrewsbury, then sent to Edinburgh to study medicine, which he hated, and a final attempt at educating him was made by sending him to Christ's College, Cambridge, to study theology (1827). During that period he loved to collect plants, insects, and geological specimens, guided by his cousin William Darwin Fox, an entomologist. His scientific inclinations were encouraged by his botany professor, John Stevens Henslow, who was instrumental, despite heavy paternal opposition, in securing a place for Darwin as a naturalist on the surveying expedition of HMS Beagle to Patagonia (1831-6).
   
Under Captain Robert Fitzroy he visited Tenerife, the Cape Verde Islands, Brazil, Montevideo, Tierra del Fuego, Buenos Aires, Valparaiso, Chile, the Galapagos Islands, Tahiti, New Zealand and Tasmania. In the Keeling Islands he devised his theory of coral reefs. During this five-year expedition he obtained intimate knowledge of the fauna, flora and the geology of many lands, which equipped him for his later investigations. By 1846 he had published several works on the geological and zoological discoveries of his voyage -works that placed him at once in the front rank of scientists. He developed a friendship with Sir Charles Lyell, became secretary of the Geological Society (1838-41) and in 1839 married his cousin Emma Wedgewood (1808-96). 

From 1842 he lived at Down House, Downe, Kent, a country gentleman among his gardens, conservatories, pigeons and fowls. The practical knowledge he gained there, especially in variation and interbreeding, proved invaluable. Private means enabled him to devote himself to science, in spite of continuous ill-health: it was not realised until after his death that he had suffered from Chagas' disease, which he had contracted from an insect bite while in South America.   

At Down House he addressed himself to the great work of his life - the problem of the origin of species. After five years of collecting the evidence he began to speculate on the subject. In 1842 he drew up his observations in some short notes, expanded in 1844 into a sketch of conclusions for his own use. These embodied the principle of natural selection, the germ of the Darwinian Theory, but with typical caution he delayed publication of his hypothesis. 

However, in 1858 Alfred Russel Wallace sent him a memoir of the Malay Archipelago, which, to Darwin's surprise, contained in essence the main ideas of his own theory of natural selection. Lyell and Joseph Hooker persuaded him to submit a paper of his own, based on his 1844 sketch, which was read simultaneously with Wallace's before the Linnean Society in 1858. Neither Darwin nor Wallace was present on that historic occasion.

Darwin then set to work to condense his vast mass of notes and put into shape his great work, The Origin of Species by Means of Natural Selection, published in 1859. This epoch-making work, received throughout Europe with the deepest interest, was violently attacked because it did not agree with the account of creation given in the Book of Genesis. But eventually it succeeded in obtaining recognition from almost all biologists.

Darwin continued to work at a series of supplemental treatises: The Fertilisation of Orchids (1862), The Variation of Plants and Animals under Domestication (1867), and The Descent of Man and Selection in Relation to Sex (1871), which postulated that the human race was derived from a hairy animal belonging to the great anthropoid group and was related to the progenitors of the orang-utan, chimpanzee and gorilla. In his 1871 work he also developed his important supplementary theory of sexual selection.

Later works include The Expression of Emotions in Man and Animals (1872), Insectivorous Plants (1875), The Effects of Cross and Self Fertilisation in the Vegetable Kingdom (1876), Different Forms of Flowers in Plants of the Same Species (1877), and The Formations of Vegetable Mould through the Action of Worms (1881).     

Darwin died after a long illness, leaving eight children, several of whom achieved great distinction. Though not the sole originator of the evolution hypothesis, nor even the first to apply the concept of descent to plants and animals, he was the first thinker to gain for that theory a wide acceptance among biological experts. By adding to the crude evolutionism of Erasmus Darwin, Lamarck and others, his own specific idea of natural selection, Darwin supplied a sufficient cause, which raised it from a hypothesis to a verifiable theory.

"Do we not therefore perceive that by the action of the laws of organization . . . nature has in favorable times, places, and climates multiplied her first germs of animality, given place to developments of their organizations, . . . and increased and diversified their organs? Then. . . aided by much time and by a slow but constant diversity of circumstances, she has gradually brought about in this respect the state of things which we now observe. How grand is this consideration, and especially how remote is it from all that is generally thought on this subject!"

Text of a lecture given by Lamarck at the Musée National d'Histoire Naturelle, Paris, May 1803

"I established the opposite view, that this history of the embryo (ontogeny) must be completed by a second, equally valuable, and closely connected branch of thought - the history of race (phylogeny). Both of these branches of evolutionary science, are, in my opinion, in the closest causal connection; this arises from the reciprocal action of the laws of heredity and adaptation... 'ontogenesis is a brief and rapid recapitulation of phylogenesis, determined by the physiological functions of heredity (generation) and adaptation (maintenance).'"

Haeckel, E. 1899. Riddle of the Universe at the Close of the Nineteenth Century.

Ernst Haeckel (1834-1919)

Ernst Haeckel, much like Herbert Spencer, was always quotable, even when wrong. Although best known for the famous statement "ontogeny recapitulates phylogeny", he also coined many words commonly used by biologists today, such as phylum, phylogeny, and ecology. On the other hand, Haeckel also stated that "politics is applied biology", a quote used by Nazi propagandists. The Nazi party, rather unfortunately, used not only Haeckel's quotes, but also Haeckel's justifications for racism, nationalism and social darwinism.

Although trained as a physician, Haeckel abandoned his practice in 1859 after reading Darwin's Origin of Species. Always suspicious of teleological and mystical explanation, Haeckel used the Origin as ammunition both to attack entrenched religious dogma and to build his own unique world view.

Hackel studied under Carl Gegenbauer in Jena for three years before becoming a professor of comparative anatomy in 1862. Between 1859 and 1866, he worked on many "invertebrate" groups, including radiolarians, poriferans (sponges) and annelids (segmented worms). He named nearly 150 new species of radiolarians during a trip to the Mediterranean. "Invertebrates" provided the fodder for most of his experimental work on development, leading to his "law of recapitulation". Haeckel was also a free-thinker who went beyond biology, dabbling in anthropology, psychology, and cosmology. Haeckel's speculative ideas and possible fudging of data, plus lack of empirical support for many of his ideas, tarnished his scientific credentials. However, he remained an immensely popular figure in Germany and was considered a hero by his countrymen.

Alfred Russel Wallace


Alfred Russel Wallace (1823-1913)

". . . Not only does the marvellous structure of each organised being involve the whole past history of the earth, but such apparently unimportant facts as the presence of certain types of plants or animals in one island rather than in another, are now shown to be dependent on the long series of past geological changes—on those marvellous astronomical revolutions which cause a periodic variation of terrestrial climates—on the apparently fortuitous action of storms and currents in the conveyance of germs—and on the endlessly varied actions and reactions of organised beings on each other. And although these various causes are far too complex in their combined action to enable us to follow them out in the case of any one species, yet their broad results are clearly recognisable; and we are thus encouraged to study more completely every detail and every anomaly in the distribution of living things, in the firm conviction that by so doing we shall obtain a fuller and clearer insight into the course of nature, and with increased confidence that the ‘mighty maze’ of Being we see everywhere around us is ‘not without a plan.’"

Island Life, Third Edition, 1911, on pages 544-545.

     "I don't know how long it is going to be before astronomers generally recognize that the combinatorial arrangement of not even one among the many thousands of biopolymers [DNA, RNA, proteins] on which life depends could have been arrived at by natural processes here on the Earth. Astronomers will have a little difficulty at understanding this because they will be assured by biologists that this is not so, the biologists having been assured in their turn by others that it is not so. The 'others' are a group of persons who believe, quite openly, in mathematical miracles. They advocate the belief that tucked away in nature, outside of normal physics, there is a law which performs miracles (provided the miracles are in the aid of biology). This curious situation sits oddly on a profession that for long has been dedicated to coming up with logical explanations of biblical miracles."

1981 Sir Fred Hoyle

    Life From Outer Space?


               Primitive Life From Mars?

A NASA research team of scientists at the Johnson Space Center (JSC), Houston, TX, and at Stanford University, Palo Alto, CA, has found evidence that strongly suggests primitive life may have existed on Mars more than 3.6 billion years ago — NASA, 7 August 1996.

You are derived from something "out there" in the sky. Seek it and you will find much more than you expect. — Fred Hoyle

"The ancient covenant is in pieces; man knows at last that he is alone in the universe's unfeeling immensity, out of which he emerged only by chance. His destiny is nowhere spelled out, nor his duty."
-- Jacques Monod

"Seen in retrospect, evolution as a whole doubtless had a general direction, from simple to complex, from dependence on to relative independence of the environment, to greater and greater autonomy of individuals, greater and greater development of sense organs and nervous systems conveying and processing information about the state of the organism's surroundings, and finally greater and greater consciousness. You can call this direction progress or by some other name." 
- Theodosius Dobzhansky

"Asymmetric molecules; I could not point out any more profound distinction between the products formed under the influence of life and all others."
- Louis Pasteur

"Even more purposeless, more void of meaning, is the world which science presents for our belief. Amid such a world, if anywhere, our ideals henceforward must find a home. That man is the product of causes which had no prevision of the end they were achieving; that his origin, his growth, his fears, his loves and his beliefs, are but the outcome of accidental collocations of atoms; that no fire, no heroism, no intensity of thought and feeling, can preserve an individual life beyond the grave; that all the labors of the ages, all the devotion, all the inspiration, all the noonday brightness of human genius, are destined to extinction in the vast death of the solar system, and the whole temper of Man's achievement must inevitably be buried beneath the debris of a universe in ruins—all these things, if not quite beyond dispute, are yet so nearly certain that no philosophy which rejects them can hope to stand. Only within the scaffolding of these truths, only on the firm foundation of unyielding despair, can the soul's habitation henceforth be safely built."

- Bertrand Russell

"... not all features of the human eye make functional sense. Some are arbitrary. To begin at the grossest level, is there a good functional reason for having two eyes? Why not one or three or some other number? Yes, there is a reason: two is better than one because they permit stereoscopic vision and the gathering of three-dimensional information about the environment. But three would be better still. We could have our stereoscopic view of what lies ahead plus another eye to warn us of what might be sneaking up behind. (I have more suggestions for improving human vision in chapter 7.) When we examine each eye from behind, we find that there are six tiny muscles that move it so that it can point in different directions. Why six? Properly spaced and coordinated, three would suffice, just as three is an adequate number of legs for a photographer's tripod. The paucity of eyes and excess of their muscles seem to have no functional explanation.

And some eye features are not merely arbitrary but clearly dysfunctional. The nerve fibers from the retinal rods and cones extend not inward toward the brain but outward toward the chamber of the eye and source of light. They have to gather into a bundle, the optic nerve, inside the eye, and exit via a hole in the retina. Even though the obstructing layer is microscopically thin, some light is lost from having to pass through the layer of nerve fibers and ganglia and especially the blood vessels that serve them. The eye is blind where the optic nerve exits through its hole. The loose application of the retina to the underlying sclera makes the eye vulnerable to the serious medical problem of detached retina. It would not be if the nerve fibers passed through the sclera and formed the optic nerve behind the eye. This functionally sensible arrangement is in fact what is found in the eye of a squid and other mollusks (as shown in the figure below), but our eyes, and those of all other vertebrates, have the functionally stupid upside-down orientation of the retina.

Paley did not really confront this problem. Little was known about mollusks' eyes at the time, and Paley merely treated the blind spots as one of the problems the eye must solve. He correctly noted that the medial position of the optic nerve exits avoids having both eyes blind to the same part of the visual field. Everything in the field is seen by at least one eye. It might also be claimed that the obstructing tissues of the retina are made as thin and transparent as possible, so as to minimize the shading of the light-sensitive layer. Unfortunately there is no way to make red blood cells transparent, and the blood vessels cast demonstrable shadows. ..."

" ... What might Paley's reaction have been to the claim, which I will elaborate in the next chapter, that mundane processes taking place throughout living nature can produce contrivances without contrivers, and that these processes produce not only functionally elegant features but also, as a kind of cumulative historical burden, the arbitrary and dysfunctional features of organisms?"

"What would Paley's reaction have been to the suggestion that the creator's wisdom is as finite as ours, and that the engineering perfection of such instruments as the eye...depends...on much trial-and-error tinkering that supplemented the creator's limited understanding? And what about the suggestion that the creator had no understanding at all, but accomplished sophisticated engineering entirely on the basis of trial and error? ..."

" ... This is no doubt true of all the implements we use: cameras, cars, computers, and even the watch that Paley reasoned must have had an intelligent designer. How far is it possible to go with trial and error alone? All the way to the human eye and hand and immune system and all the other well-engineered machinery by which we, and all other organisms, solve the problems of life...

Darwin was challenged repeatedly on this matter. Critics would point to the precision and design features of the eye and claim that an organ of this perfection could not possibly have been produced by an accumulation of small changes, each of which made the eye work slightly better. A grossly imperfect eye, which could be improved by this process, would supposedly never evolve in the first place. Slight improvements in one part, such as the retina, would be useless without an exactly matching improvement in another, such as an increased precision of the lens. This is an utterly fallacious kind of reasoning. An improved retina may be useless without an improved lens, but both retinas and lenses are subject to individual variation. Some of the better retinas would be found in individuals who also had better lenses, so that the improvements, on average, could be favored.

The criticisms were also factually erroneous, and their proponents were ignorant of biology. As Darwin pointed out, familiarity with the animal kingdom shows the existence today of just about every stage in a plausible sequence from primitive light-sensitive cells on the surfaces of tiny wormlike animals, through the rudimentary camera eyes of scallops, to the advanced optical instrumentation of squids and vertebrates. Every stage in this sequence is subject to variation, and every stage is clearly useful to its possessor. ..."

- George Williams