[HOME PAGE] [CURRICULUM VITAE] [DRAFTS AND SKETCHES]
Debates over the relative merits of intelligent design (ID) versus Darwinian natural selection as scientific/rational explanations for the existing diversity and complexity of life on the Earth are fairly common in the Christianity General forums on About.com. These can become quite heated on both sides.
Some of those on the ID side are strong creationists and are fighting either to discredit the Darwinian theory of evolution (as a perceived threat to their dogmatic faith that their reading of the bible is the sole and only truth about the nature of the world), or at least to force schools to treat ID as an alternative theory to natural selection that is equally scientific.
Most of those posting to the religion forums on natural selection are concerned that the creationist/ID forces are working to prevent evolution from being taught at all and as a result inhibiting the teaching of any scientific rationality in the schools, as has been the case in the last few years in Kansas.
Both sides see the other as attacking their own personal and fundamental "belief systems" (here, I prefer to use the word epistemology in place of belief) and thus people feel they are personally threatened - which leads to emotionally heated ad hominem attacks rather than reasoned argument and debate.
As I have noted in several of my previous postings on this forum, I think dogmatic fundamentalism as a major threat to the values of Western rational culture, given that it has the power to turn human beings into guided weapons of mass destruction - as demonstrated on 9/11 and more recently - especially for Australians - in Bali in Indonesia where almost as many holidaying Australians were killed in proportion to our population as was the case in the US on 9/11. See Time to declare war on fundmentalism for my response to the 9/11 tradgedy.
The moves, largely driven by fundamentalist Christians, to force the so-called "scientific" creationism - or failing that its step-child "intelligent" design into US schools as a substitute for or on at least equal footing with the rationally scientific theory of natural selection and the teaching of evolutionary bases of astronomy and cosmology, geology and biology.
I have little power to influence the true dogmatic fundamentalist who accepts their group's interpretation of the Bible as the absolute literal truth. However, I would like to give those of you who accept the creationist or intelligent design arguments as worthy of consideration because you lack the knowledge to rationally discriminate between them something to think about.
My previous attempts along these lines are as follows.
The Second Law of Thermodynamics and the Origin of Life - http://forums.about.com/ab-christianity/messages?msg=8657.42
Why the "argument from design" doesn't hold water - http://forums.about.com/ab-christianity/messages?msg=9881.141
On Books, Larvae, Marine Life and the Evolution of Diversity http://forums.about.com/ab-christianity/messages?msg=10917.2462
Following the last essay, JJHAMILX (see http://forums.about.com/n/mb/message.asp?webtag=ab-christianity&msg=10917.2482) invited me to respond to the argument on the following web sites:
Collins's comments are little more than assertions and do not expose an epistemology that can be argued. The closest I can come to a reasoned argument is expressed in the following extract:
... Science is predicated upon the assumption that the universe is self-consistent and not capricious. It fundamentally assumes that all physical laws are invariably obeyed in all places and at all timesůa theological concept that derives from the biblical picture of a single, transcendent, unchanging God.
Lately, however, the concept of natural law has come into question. First of all, now that the Big Bang theory is almost universally accepted, the origin of natural laws cannot be explained. Second, on a subatomic level, exceptions to natural laws can be observed. This has caused many scientists to define natural laws as tendencies or statistical probabilities; but this actually restates the problem rather than solving it: for why should probability produce tendencies and not randomness?
So, more than creationists realize, science is beginning to discover that the universe is the way it is only because God wants it that way. The universe is sustained each moment in its existence because God directly and personally wills it. What we call Žnatural lawŪ is nothing more than evidence that God generally wills the same things.
I am the first to admit that there are are metaphysical questions about the origin of the universe or what might lie outside of it that are entirely beyond the bounds of what we can logically predict or speculate about based on what we currently know of physical law. In other words, physics and all science derived from it has nothing to say one way or the other about whether a creator exists outside of the physical bounds of self-consistent science. However, the science that has been rationally built within the realm of known space as described by physical law is internally consistent and conformant, and I see nothing anywhere in the overall body of science that requires or even suggests the existence of supernatural interference in the self-consistent workings of this universe.
By way of qualification, what have just said should not to be interpreted that we know all the science there is to know, or that new discoveries won't be made that cause radical alterations in this understanding. In the past, relativity - on the largest scales of physics, followed by quantum mechanics - on the most infinitesimal scales of physics both led to major revolutions in science, but did not require supernatural explanations to bring the pieces together again in a self-consistent understanding. We are probably on the threshold of another major revolution on our understanding of the physical world, in that astronomers and cosmologists (at an even larger scale than addressed by relativity) are finding a number of inconsistencies that suggest that our present understanding of gravitation on the scale of galaxies and larger, and time and space on dimensions comparable to the size of the visible universe (i.e., 10-20 billion light years), do not adequately explain observations by the latest generations of ground and space-based telescopes. However, on the scale of life on a minor planet revolving around a medium bright main-sequence star, it is highly unlikely that what we don't know about physics will have any impact on the understandings I will discuss below.
I don't intend to discuss Collins fundamentally vacuous statements further, but Behe (loc. cit.) has stated a position based on logical positions assuming that some supernatural designer has interfered to create complexity that could not have evolved within the self-consistent laws deriving from physical foundations. Behe's claims are susceptible to critical analysis, discussion and comparison with alternative explanations for the same features of life. Hopefully the following extract will briefly state his position without doing any injustices:
...the complex design of the cell has provoked me to stake out a distinctly minority view among scientists on the question of what caused evolution. I believe that Darwin's mechanism for evolution doesn't explain much of what is seen under a microscope. Cells are simply too complex to have evolved randomly; intelligence was required to produce them.
I want to be explicit about what I am, and am not, questioning. The word "evolution" carries many associations. Usually it means common descent -- the idea that all organisms living and dead are related by common ancestry. I have no quarrel with the idea of common descent, and continue to think it explains similarities among species. By itself, however, common descent doesn't explain the vast differences among species.
That's where Darwin's mechanism comes in. "Evolution" also sometimes implies that random mutation and natural selection powered the changes in life. The idea is that just by chance an animal was born that was slightly faster or stronger than its siblings. Its descendants inherited the change and eventually won the contest of survival over the descendants of other members of the species. Over time, repetition of the process resulted in great changes -- and, indeed, wholly different animals.
That's the theory. A practical difficulty, however, is that one can't test the theory from fossils. To really test the theory, one has to observe contemporary change in the wild, in the laboratory or at least reconstruct a detailed pathway that might have led to a certain adaptation.
Darwin's theory encounters its greatest difficulties when it comes to explaining the development of the cell. Many cellular systems are what I term "irreducibly complex." That means the system needs several components before it can work properly. An everyday example of irreducible complexity is a mousetrap, built of several pieces (platform, hammer, spring and so on). Such a system probably cannot be put together in a Darwinian manner, gradually improving its function. You can't catch a mouse with just the platform and then catch a few more by adding the spring. All the pieces have to be in place before you catch any mice.
An example of an irreducibly complex cellular system is the bacterial flagellum: a rotary propeller, powered by a flow of acid, that bacteria use to swim. The flagellum requires a number of parts before it works -- a rotor, stator and motor. Furthermore, genetic studies have shown that about 40 different kinds of proteins are needed to produce a working flagellum.
The intracellular transport system is also quite complex. Plant and animal cells are divided into many discrete compartments; supplies, including enzymes and proteins, have to be shipped between these compartments. Some supplies are packaged into molecular trucks, and each truck has a key that will fit only the lock of its particular cellular destination. Other proteins act as loading docks, opening the truck and letting the contents into the destination compartment.
Many other examples could be cited. The bottom line is that the cell -- the very basis of life -- is staggeringly complex. But doesn't science already have answers, or partial answers, for how these systems originated? No. As James Shapiro, a biochemist at the University of Chicago, wrote, "There are no detailed Darwinian accounts for the evolution of any fundamental biochemical or cellular system, only a variety of wishful speculations."
A few scientists have suggested non-Darwinian theories to account for the cell, but I don't find them persuasive. Instead, I think that the complex systems were designed -- purposely arranged by an intelligent agent.
Reducing Behe's argument to a single sentence: 'Cellular structure and metabolism as we know them are too complex to have evolved through through the self-consistent processes of genetic variation and natural selection; therefore an "intelligent" designer was required to "produce" them.' Readers interested in more detail on Behe's thinking should at least see http://www.arn.org/docs/behe/mb_philosophicalobjectionsresponse.htm and other documents available through the Michael J. Behe Resource Page on the anti-evolutionist Access Research Network site - http://www.arn.org/index.html.
I'll present my plan for the rest of the document (which will be posted in parts) here to conclude this introduction.
Part 1, reviews some of the epistemological foundations of science, what criteria one can use to distinguish between good science and non science, and considers how Behe's proposal fits within the. Behe's philosophical objections response cited above greatly oversimplifies and parodies scientific methodology.
Part 2, briefly reviews some of the core concepts in the theory of evolution based on variation and natural selection and my own background to discuss evolution and epistemology.
Part 3, provides a definition for what constitutes life, reviews some of the thermodynamic principles underlying the phenomenon of life, and consider the kinds of circumstances under which entities conforming to these properties could have plausibly arisen.
Part 4, briefly reviews the kinds of selection pressures and genetic systems likely to have existed early in life's existence and how cell structures as we know them today could plausibly have evolved without requiring the hand of an "intelligent" designer.
Part 5, ties this in to the limited evidence from the geological and fossil record regarding early life.
Most of the evidence supporting this hypothetical reconstruction already existed in the 1960's and 1970's. As an aspiring biology student a core question was always "what is life" and "how do things with the property of life differ from dead and non-living things"; and, of course, "how did life come to be". My answers, as presented in the following sections were developed in 1966 and were presented as a term paper in a Washington University (St Louis) genetics and evolution course, and in the introductory lectures for an invertebrate zoology course I was teaching at Southern Illinois University, Edwardsville. Some of the answers I developed in 1966 were finally published and publicised by Lynn Margulies (then or somewhat later the wife of Carl Sagan) in her ground breaking book on the endosymbiosis hypothesis. The endosymbiosis hypothesis claims that chloroplasts evolved through the symbiosis of blue green algea and a nucleated cell and that mitochondria (source of oxygen using metabolism) evolved through the symbiosis of nucleated cells and bacteria that had previously evolved the capacity for oxidative metabolism, Origin of Eukaryote Cells. (I am not claiming priority here - I was in no position academically to publish in the area and there would have been no way she could have been familiar with my ideas.) However, as I will show below, the evidence to support the hypothesis was beginning to accumulate, and the time was ripe in 1966 to put it together.
My personal history is an important basis for understanding how I developed answers for these questions. Because there are still original aspects in these answers, I think this history forms an essential part of the story to help readers assess the quality of the thinking and evidence used in constructing the answers.
As I mentioned in "On Books, Larvae, Marine Life and the Evolution of Diversity" (link above), I grew up in marine habitats after WW II (i.e., my family lived on a boat which we kept in Southern California marinas and spent many weekends and summer holidays in the essentially pristine bays of Santa Catalina Island immersed in tide pools for many hours of the day). My father had studied geology and I literally learned to read (but not until the third grade!) using his textbooks and other books from the library, driven by my interest in palaeontology and biology. Dinosaurs were a prime interest, but given my father's interests in economic geology and stratigraphy, I was well aware of the diversity of marine invertebrate fossils used to demarcate various oil-bearing formations. I also had used a good quality compound microscope even before I started junior high school. (A neighbour who was a photographer observed my interests and gave me good quality achromatic 10 X and 40 X objective lenses he had left over from a project that turned a cheap and nasty toy store microscope set into a near research quality instrument). This opened my eyes to the world of the very small. However, even when fuelled by a marvellous high school biology course, biology remained only a time-consuming hobby as I had every intention to be an engineer and build space ships.
College quickly convinced me that engineering was nothing but arithmetic that I do badly because of a slight dyslexia, but that physics was about ideas and was the king of sciences. After three years of physics (first two with B's and A's at a small Christian college except for maths), my lack of mathematical aptitude and drop in grades when I transferred to UCLA convinced me that I would never have the capacity to be on the leading edge of research. In my junior year I also took general zoology and (because I also bred tropical fish and shared a flat with a graduate student in psychology) I took a graduate seminar course in ethology/animal behaviour. I easily earned A grades in both while I was flunking the computationally intensive analytical mechanics and electrical measurements and theory lab courses (before the days of hand calculators - when all calculations had to be done longhand!), and it dawned on me that one could study biology as a profession as well as physics. To pay the costs of my education (my parents paid for my first two years at the small Christian college, but after that I had to pay essentially all my education costs myself, which is why I transferred to UCLA. I also worked part time and full time summers, as a research technician in a hospital neurophysiology research lab.
Half way through my senior year I changed majors to zoology and started over part time at San Diego State University. My first course there was Comparative Anatomy of the Vertebrates that was organised using a Darwinian comparative paradigm (at the time this was all implicit - no thought was actually given to explaining why the material was presented the way it was). I found the framework so useful that I finished the course with something like three or four points short of a perfect exam score. (Note, I eventually researched and published the epistemological basis for this paradigm in Hall (1983), and will forward an electronic version of the paper to anyone who requests it). Given my interests in the microscopic aspects of life, and the fact that my advisor was a herpetologist, by the time I was ready to graduate I already had a well developed masters degree project to study chromosome evolution in lizards. I started this as a part time student at San Diego State but had a full time job as an ecology research technician for the UCLA Laboratory of Nuclear Medicine and Radiation Biology at the Nevada Test Site, which was something like a 300 mile commute.
In any event, after 7 1/2 years of part time studies and work as a research assistant in a variety of disciplines from biophysics to primatology, I finally earned my BS in Zoology, and managed to convince UCLA to provide me with suitable lab facilities at the Nevada Test Site, so I was able to collect enough data to establish a sound basis for a thesis proposal, that might allow me entry into a graduate school where I would be able to spend full time on my studies. In some regards the Nevada Test Site job was extremely productive. Approximately half the work was studying population dynamics and biology of lizards that had been exposed to low levels of radiation over a long period (from a controlled source in a tower that was shielded when we were in the field), and one of the other technicians was a classmate from San Diego State, who was a fanatic collector who financed several field trips into the heartland of iguanid lizard diversity in western Mexico.
From 1960 to 1965 I managed to maintain unrestricted faculty access to what may have been the greatest biology research library the world has ever known. During this period the UCLA Biomedical Library could well have had the most comprehensive collection of biological materials in the world due to the fact that the university was very strong in both biology and medicine and was able to organise all the medical and biological journals in the single cataloguing and shelving system. Because it was directly attached to the UCLA Medical Center Hospital it was also open 24 hours a day, including weekends! When I started work in the neurophysiology research lab, I gained academic borrowing privileges to the UCLA Biomedical Library by serving as a go-between between the professor leading the lab and the library and could check out anything that interested me, including bound journals. When I moved to San Diego, based on my prior experience at UCLA, I was able to maintain full academic privileges to the the Biomedical Library by continuing my association with the neurophysiology research lab, and when that closed when leader died of cancer, I was able to operate the same ploy in the name of my course advisor at San Diego State. While working from San Diego or the Nevada Test Site, I had enough friends in the LA area so I could easily find a place to camp overnight to spend the whole weekend in the library.
However, when I completed by BS, my transcript (already involving three different tertiary educations with A's and F's) was so complex and confusing, that the only offer I had for graduate work was from a fellow herpetologist who was chairman of the biology department for at the still to be opened Edwardsville campus of Southern Illinois University (for the first year we used the campus of a bankrupt private college in Alton, Illinois). He was desperate for teaching assistance and had seen enough of my work to think I had something to offer, so he offered me a place in his non-existent masters degree program and a teaching position as an "assistant lecturer", where for two years from 1965-1967 I taught the comparative anatomy labs and my second year taught the entire invertebrate zoology courses (based primarily on my background knowledge of the diversity of marine organisms). Given that I was teaching a lab course in invertebrate zoology and we had a new campus (now open) to equip I was able write my own ticket for teaching materials. Given that most of my background was with living marine organisms, I was able to equip the lab with a couple of cooled 50 gallon marine aquaria with robust filtration systems; and through a biological supply house, I was able to order a small number (3-4) Styrofoam boxes of live material from the California coastline (e.g., molluscs, anemones (on rocks), polychaete worms, seaweeds with everything living on them and the like). Given my knowledge of the very small, I mounted operating microscopes (stereo dissecting microscopes) mounted in swivel heads on a long arm allowing the microscopes to be pointed in any direction - including horizontally through the side of an aquarium. The tanks were good enough, that most of the live material was maintained in good health for the duration of the course even though we were in the midst of the Midwest corn belt. This allowed us (mostly me) to find and observe the daily lives of virtually all marine phyla and a substantial fraction of classes within phyla (many of which are microscopic or near microscopic and quite unknown to 99% of terrestrial biologists). Also, once I started work on lizard chromosomes I had "ownership" of top of the line phase contrast optical microscopes offering close to the maximum magnification that can be achieved with light waves. Although purchased for the study of chromosomes, given that I normally had some kind of aquarium close to hand, I was of course able to continue my early interest in protozoa, and protozoan genetic systems.
To test and prove my academic credibility in the best university environment the greater St Louis environment offered, I also enrolled in Washington University (St Louis) as a fee-paying part time student to take the year-long genetics and evolution course taught by Hampton Carson, one of the world's leading Drosophila (fruit fly) geneticists of the day. With his support, I started Carson's course half way through in the second term, and finished the first term in the next year. Given that I had a genuine academic teaching appointment at Southern Illinois University, I was again able to gain academic vs student privileges to the Washington University research library, the best Missouri or southern Illinois had to offer.
My hypothetical reconstruction of the early evolution of life on the Earth presented below was developed at that time in that environment - when I still had close to zero academic credibility, teaching without a degree in what would have been one of the lowest ranked universities at the time. However, I had available an depth of experience in the diversity of life that would not have been matched by many other people anywhere and the tools, interest and incentive to try to comprehend how that diversity came to be.
To credibly organise lectures and labs for, and teach from scratch a major course I had not even taken, I made an early decision to use the evolutionarily-based comparative methodology that had worked so spectacularly well for me in comparative vertebrate anatomy to organise what I knew and could find out about the range of invertebrate diversity. This includes everything from amoebas and many kinds of parasitic organisms to corals, worms, squids, octopuses, lobsters, bees and beetles - comprising over 90% of all animal species - even if insects are excluded). I had to do this while performing credibly in the courses I was taking both at SIU,E and at Washington University and assisting in the comparative anatomy and vertebrate biology courses taught by the department chairman, and working on my thesis (the full summer was spent in the field chasing lizards to be used in my research program).
I will close off this segment with the bibliography I intend to use. Most of the citations date from my teaching career, and a few were actually available to me when I originally put the ideas together. Except for the Fox book on thermal proteinoids which I have owned but couldn't find and another on loan, all of the books cited are a small part of my own personal library. The bibliography does not include journal citations. I believe I still have many reprints from the 60's and 70's relating to the subjects presented here, but they are stored away in boxes in my carport, and there is no way I have time to dig out and organise them. Most have survived the winnowing of five overseas and several transcontinental moves plus water damage from a leaking garage roof when I couldn't afford the shelving to house them properly. The titles are more-or-less organised in sections corresponding to the intended sections of the essay. I hope to finish the essay by the end of the weekend (or next at the latest) because I am in the middle of a book project in an evolutionary framework relating to my current professional area of organisational knowledge management, and this essay is very much a side issue (although it may well form the basis for a later book if I can afford the time to do it right).
[Note: I will use illustrations in some of the future installments, but I will have to alter my login name to do so because I have filled up my attachment space with those used in the previous postings. I will endeavour to cross link the posts so they can be read in sequence.]
1. Fumerton, R., (2000), Foundationalist Theories of Epistemic Justification in - Zalta, E.N. ed. Stanford Encyclopedia of Philosoply - http://setis.library.usyd.edu.au/stanford/entries/justep-foundational/
2. Hall, W.P. 1983. Modes of speciation and evolution in the sceloporine iguanid lizards. I. Epistemology of the comparative approach and introduction to the problem. (in) A.G.J. Rhodin and K. Miyata, eds. Advances in Herpetology and Evolutionary Biology - Essays in Honor of Ernest E Williams. Museum of Comparative Zoology, Cambridge Mass. pp.643-679
3. Kuhn, T.S. 1970. The Structure of Scientific Revolutions, 2nd. Ed. Enlarged. International Encyclopedia of Unified Science 2(2). University of Chicago Press, Chicago.
4. Kuhn, T.S. 2000. The Road Since Structure: Philosophical Essays, 1970-1993, with an Autobiographical Interview. J. Conant and J. Haugeland [eds.]. The University of Chicago Press, Chicago.
5. Polanyi Michael (1958): Personal Knowledge: Towards a Post-Critical Philosophy. University of Chicago Press.
6. _____. (1966): The Tacit Dimension. Doubleday & Co.
7. Popper, K.R. (1934, 1959). The Logic of Scientific Discovery, Sixth Impression (Revised) [First English Ed., Hutchinson, 1959. First published as Logik Der Forschung in Vienna: Springer, 1934]. London, Hutchinson & Co., Ltd., 480 pp.
8. ____. (1963, 1972a). Conjectures and Refutations: The Growth of Scientific Knowledge, 4th Ed. (Revised) [1st Ed., 1963]. London, Routledge and Kegan Paul, 431 pp.
9. ____. (1972b). Objective Knowledge: An Evolutionary Approach. London, Oxford Univ. Press, 380 pp.
10. Suppe, F. 1977. [Editor] The Structure of Scientific Theories. 2nd Ed., University of Illinois Press.
11. Thornton, S. (2000). Karl Popper. in The Stanford Encyclopedia of Philosophy (Winter 2001 Edition), Edward N. Zalta (ed.), . - http://plato.stanford.edu/archives/win2001/entries/popper/
12. Eldridge, N. and and Gould, S.J. 1972. "Punctuated equilibria: an alternative to phyletic gradualism," in Models in Paleobiology. T.J.M. Schopf (ed.). San Francisco: Freeman, Cooper. pp. 82-115.
13. Gould, S.J. 2002. The Structure of Evolutionary Theory. Belknap Press of Harvard University Press. Cambridge, Mass.
14. Hall, W.P. (1973). Comparative population cytogenetics, speciation and evolution of the iguanid lizard genus Sceloporus. PhD Thesis, Harvard University
14. Mayr, E. 2001. What Evolution Is. Basic Books [Phoenix Paperbacks - UK ed published 2002].
16. O'Neil, D. (2002). Synthetic Theory of Evolution: An Introduction to Modern Evolutionary Concepts and Theories. - http://anthro.palomar.edu/synthetic/ [http://web.archive.org/web/*/http://anthro.palomar.edu/synthetic/].
17. Sites, J.W., et. al. (1992). A review of phylogenetic hypotheses for lizards of the genus Sceloporus (Phrynosomatidae): Implications for ecological and evolutionary studies. Bull. Am. Mus. Nat. Hist., No. 213, 110 pp.
18. Blum, H.F. 1955. Time's Arrow and Evolution. Princeton University Press. [Harper Torchbooks Edition, 1962]
19. Chaisson, E.J. 2001. Cosmic Evolution: The Rise of Complexity in Nature. Harvard University Press, Cambridge, Mass.
20. Fay, J.A. 1965. Molecular Thermodynamics. Addison-Wesley, Reading, Mass.
21. Gates, D.M. 1962. Energy Exchange in the Biosphere. Harper & Row Biological Monographs. Harper & Row, Publishers, New York
22. Katchalsky, A & Curran P.F. 1965. Nonequilibrium Thermodynamics in Biophysics. Harvard Books in Biophysics, 1. Harvard University Press, Cambridge, Mass.
23. Kauzmann, W.K. 1967. Thermodynamics and Statistics: With Application to Gasses. Physical Chemistry Monograph Series. Thermal Properties of Matter, Vo. 2. W.A. Benjamin, Inc., New York
24. Levy, S. 1992. Artificial Life: The Quest for a New Creation. Jonathan Cape [Penguin Books Edition]
25. Maturana, H.R. and Varela, F.J.1980. Autopoiesis and Cognition: The Realization of the Living. Boston Studies in the Philosophy of Science, Vol 42. D. Reidel Publishing Company.
26. Morowitz, H.J. 1968. Energy Flow in Biology: Biological Organization as a Problem in Thermal Physics. Academic Press, New York.
27. Morowitz, H.J. 1970. Entropy for Biologists: An Introduction to Thermodynamics. Academic Press, New York.
28. Plotkin, H. 1994. Darwin Machines and the Nature of Knowledge. Harvard University Press, Cambridge, Mass.
29. Reiner, J.M. 1968. The Organism as an Adaptive Control System. Prentice-Hall, Inc., Englewood Cliffs, N.J.
30. Fox, S.W. & Dose, K. 1972. Molecular Evolution and the Origin of Life, Freeman Pub. Co., San Francisco [not found]
31. Miller, S.L. and Orgel, L.E. 1974. The Origins of Life on the Earth. Prentice-Hall, Inc. Englewood Cliffs, N.J.
32. Oparin, A.I. 1938. Origin of Life. The Macmillan Company. [Dover Publications, Inc. 1953 reprint edition]
33. Rohlfing, D.L. and A.I. Oparin. 1972. [Editors] Molecular Evolution: Prebiological and Biological [Sidney Fox 60th birthday festschrift. Plenum Press, New York.
34. Schoffeniels, E. 1971. Molecular Evolution II: Biochemical Evolution and the Origin of Life. Proceedings of the International Conference on Biochemical Evolution. North-Holland Publishing Company, Amsterdam.
35. Ward, P.D. 2000. Rare Earth: Why Complex Life is Uncommon in the Universe. Copernicus: Springer-Verlag, New York.
36. Anderson, O.R. 1987. Comparative Protozoology: Ecology, Physiology, Life History. Springer-Verlag, Berlin
37. Beale, G. & Knowles, J. 1978. Extranuclear Genetics. Edward Arnold, London.
38. Dustin, P. 1978. Microtubules. Springer-Verlag, Berlin.
39. Goldsby, R.A. 1977. Cells and Energy. 2nd Ed. Macmillan Publishing Co., Inc., New York.
40. Grun, P., 1976. Cytoplasmic Genetics and Evolution. Columbia University Press, New York.
41. Kirk, J.T.O & Tilney-Bassett, R.A.E. 1967. The Plastids: Their Chemistry, Structure, Growth and Inheritance. W.H. Freeman and Company, London.
42. Kudo, R.R. 1971. Protozoology. 5th Ed., Charles C. Thomas, Springfield, Ill.
43. Lehninger, A.L. 1975. Biochemistry [2nd Ed.] Worth Publishers, Inc., New York
44. Lewin, R.A. 1976. [editor] The Genetics of Algea. Botanical Monographs 12. University of California Press, Berkeley.
45. Lloyd, D. 1974. The Mitochondria of Microorganisms. Academic Press. London.
46. Manwell, R.D. 1968. Introduction to Protozoology. 2nd Ed. Revised. Dover Publications, Inc., New York
47. Margulies, L. 1970. Origin of Eukaryote Cells: Evidence and Research Implications for a Theory of the Origin and Evolution of Microbial, Plant, and Animal Cells on the Precambrian Earth. Yale University Press, New Haven, Ct.
48. Briggs, D.E.G., Erwin, D.H. & Collier, F.J. 1994. The Fossils of the Burgess Shale.
49. Gould, S.J. 1989. Wonderful Life: The Burgess Shale and the Nature of History. Penguin Books Edition.
50. Schopf, J.W. 1999. Cradle of Life: The Discovery of Earth's Earliest Fossils. Princeton University Press, Princeton, N.J.
51. Shrock, R.R. & Twenhofel, W.H. 1953. Principles of Invertebrate Paleontology.. McGraw-Hill Book Company, Inc., New York.
52. Tasch, P. 1973. Paleobiology of the Invertebrates: Data Retrieval from the Fossil Record. John Wiliey & Sons, New york
53. Novikoff, A.B. & Holtzman. 1976. Cells and Organelles. 2nd Ed., Holt, Rinehart and Winston. New York.
54. Reinert, J. & Ursprung, H. 1971. Origin and Continuity of Cell Organelles. Springer-Verlag, New York
55. Roodyn, D.B. and Wilkie, D. 1968. The Biogenesis of Mitochondria. Methuen & Co., Ltd. London.
56. Sager, R. 1972. Cytoplasmic Genes and Organelles. Academic Press, New York.