Stephen E. Jones

Projects: "Problems of Evolution" (Outline): 8. Cell & Molecular (1)

[Home] [Site map] [Updates] [Projects] [Contents; 1. Introduction; 2. Philosophy (1), (2), (3), (4) & (5); 3. Religion (1) & (2); 4. History (1), (2) & (3); 5. Science; 6. Environment (1), (2) & (3); 7. Origin of life (1), (2) & (3); 8. Cell & Molecular (2) & (3); 9. Mechanisms (1), (2) & (3); 10. Fossil Record; 11. `Fact' of Evolution; 12. Plants; 13. Animals; 14. Man (1) & (2); 15. Social; 16. Conclusion; Notes; Bibliography A-C, D-F, G-I, J-M, N-S, T-Z] [Book "Problems of Evolution"]



"PROBLEMS OF EVOLUTION": 8. CELL & MOLECULAR (1)
1.	Cell
	1.	Origin of life is origin of cell
		1.	Cell is the basic unit of life
		2.	Cell is the basic unit of reproduction
		3.	The origin of life is the origin of the first single-celled organism
		4.	The simplest living cell is highly complex
	2.	Cell's technology is beyond the ability of science to duplicate
	3.	Cell is a Von Neumann machine
		1.	It is far more a problem than Hoyle's whirlwind in a junkyard assembling a Boeing 747
	4.	Information content of a cell
	5.	The minimal cell
		1.	Minimum size of cell
		2.	Minimum number of genes
		3.	Minimum number of proteins
		4.	Minimum number of gene products (proteins, RNAs)
	6.	The first cell was irreducibly complex
	7.	Assembly of first cell was fantastically improbable

2.	Molecular
	1.	Genetic code(s)
	2.	DNA
	3.	Proteins
	4.	Enzymes
	5.	Molecular machinery

3.	Problem of sex
4.	Eukaryotes


"PROBLEMS OF EVOLUTION": 8. CELL & MOLECULAR (1)
1.	Cell
	1.	Origin of life is origin of cell
"Although a biologist, I must confess that I do not understand how life came about. Of course, it depends on the definition of life. To me, autoreplication of a macromolecule does not yet represent life. Even a viral particle is not a life organism, it only can participate in life processes when it succeeds in becoming part of a living host cell. Therefore, I consider that life only starts at the level of a functional cell. The most primitive cells may require at least several hundred different specific biological macromolecules. How such already quite complex structures may have come together, remains a mystery to me. The possibility of the existence of a Creator, of God, represents to me a satisfactory solution to this problem." (Arber, Werner [Professor of Microbiology at the University of Basel, Switzerland, shared Nobel Prize for Physiology/Medicine in 1978.], "The Existence of a Creator Represents a Satisfactory Solution," in Margenau H. & Varghese R.A., eds., "Cosmos, Bios, Theos: Scientists Reflect on Science, God, and the Origins of the Universe Life, and *Homo Sapiens*," [1992], Open Court: La Salle IL, 1993, Second Printing, pp.142-143) [top]
1. Cell is the basic unit of life
"The cell is the basic unit of biology. Every organism either consists of cells or is itself a single cell." (Becker W.M., Kleinsmith L.J. & Hardin J., "The World of the Cell," [1986], Benjamin/Cummings: San Francisco CA, Fourth edition, 2000, p.2)
"All living creatures are made of cells-small membrane-bounded compartments with a concentrated aqueous solution of chemicals. The simplest forms of life are solitary cells that propagate by dividing in two. Higher organisms, such ourselves, are like cellular cities in which groups of cells perform specialized functions and are linked by intricate systems of communication." (Alberts B., et al., "Molecular Biology of the Cell," [1983], Garland: New York NY, Third Edition, 1994, p.3) [top]
2. Cell is the basic unit of reproduction
"By 1855, Rudolf Virchow, a German physiologist, was able to conclude that cells arose in only one manner-by the division of other, preexisting cells. Virchow encapsulated this conclusion in the now-famous Latin phrase omnis cellula e cellula, which in translation becomes the third tenet of the modern cell theory: 3. All cells arise only from preexisting cells. Thus, the cell is not only the basic unit of structure for all organisms but also the basic unit of reproduction. In other words, all of life has a cellular basis. " (Becker W.M., Kleinsmith L.J. & Hardin J., "The World of the Cell," [1986], Benjamin/Cummings: San Francisco CA, Fourth edition, 2000, p.4)
"The cell theory, one of the fundamental unifying concepts of biology, states that all living things are composed of basic units called cells and of substances produced by cells." (Solomon E.P., Berg L.R., Martin D.W. & Villee C.A., "Biology," [1985], Harcourt Brace: Orlando FL, Third Edition, 1993, pp.3-4) [top]
3. The origin of life is the origin of the first single-celled organism
"The question of how life began is more specifically about the genesis of prokaryotes. Sometime between about 4.0 billion years ago, when Earth's crust began to solidify, and 3.5 billion years ago, when the planet was inhabited by bacteria advanced enough to build stromatolites, the first organisms came into being." (Campbell N.A., Reece J.B. & Mitchell L.G., "Biology," [1987], Benjamin/Cummings: Menlo Park CA, Fifth Edition, 1999, p.492) [top]
4. The simplest living cell is highly complex
"Above the level of the virus, if that be granted status as an organism, the simplest living unit is almost incredibly complex. It has become commonplace to speak of evolution from ameba to man, as if the ameba were a natural and simple beginning of the process. On the contrary, if, as must almost necessarily be true short of miracles, life arose as a living molecule or protogene, the progression from this stage to that of the ameba is at least as great as from ameba to man. All the essential problems of living organism are already solved in the one-celled (or, as many now prefer to say, noncellular) protozoan and these are only elaborated in man or the other multicellular animals." (Simpson G.G., "The Meaning of Evolution: A Study of the History of Life and of its Significance for Man," [1949], Yale University Press: New Haven CT, 1960, reprint, pp.15-16)
"I will grant that the path of chemical evolution seems sensible and in the right direction. There are a few obvious puddles to be avoided and some of the flagstones are a bit uneven, perhaps. but there is the promise of an easy walk up to the foothills of the mountain that we can see straight ahead of us. It is a promise that is unfulfilled. The trouble with this path is that it leads us toward, but it does not lead us to expect, a sudden near- vertical cliff-face. Suddenly in our thinking we are faced with the seemingly unequivocal need for a fully working machine of incredible complexity: a machine that has to be complex, it seems. not just to work well but to work at all." (Cairns-Smith A.G., "Seven Clues to the Origin of Life: A Scientific Detective Story," Cambridge University Press: Cambridge, 1993 reprint, p.37) [top]
2. Cell's technology is beyond the ability of science to duplicate The cell's technology is beyond the ability of modern science to duplicate. A molecular biology textbook considers whether "In these days of astounding advances in science and technology" whether "the artificial synthesis of a living cell is impossible" and answers it with a question, asking "on what sort of microloom would a biologist weave the membranes of the endoplasmic reticulum, or with what delicate needles could a biologist fashion the intricacies of the cell nucleus?" (Price F.W., 1979, p.466). [top] 3. Cell is a Von Neumann machine As Denton, a molecular biologist, points out, the cell is a fully automatic self-replicating system, a "von Neumann machine" (Denton, 1985, p.269). As the mathematician Von Neumann pointed out in 1951, the construction of any sort of self-replicating automaton would necessarily require the solution of three fundamental problems: 1) storing information; 2) duplicating information; and 3) an automatic factory that could be programmed from the information stored to construct all the other components of the machine as well as duplicating itself (Denton, 1985, pp.269; 337; Langton, 1995, p.352; (Gould, 1985, p.405). Von Neumann envisaged such an automaton consisting of two components: an information bank and a mechanical assembly unit capable called the "constructor" (Denton, 1998, p.144). The information bank provided all the information and instructions necessary to direct the constructor to not only assemble a copy of itself but also make a copy of the information bank and insert it into the newly assembled constructor, so that the automaton makes a complete copy of itself (Denton, 1998, p.144; Scott, 1986, p.197). There would also need to be a fuel supply to provide energy which von Neumann's model did not seriously consider (Denton, 1998, p.147). However, the practical difficulties of converting the dream of a self-replicating automaton into reality have proved too daunting (Denton, 1985, p.337; Cairns-Smith, 1985, p.14). As yet no machine can replicate itself (Denton, 1998, p.147). Not only that but after half a century, this dream is nowhere near realization, there not even existing a detailed blueprint of a machine that could carry out self-replication (Denton, 1998, p.147; Gould, 1985, p.413). The challenges are enormous, for example, a self-replicating machine requires that the data storage system be accessible and comprehensible to the constructor device (Denton, 1998, p.147). The constructor be must be able to be assembled from readily available materials and requires a means of energy generation, storage and distribution, but none of these problems has been solved (Denton, 1998, p.147). Yet the living cell follows the principles von Neumann had outlined (Drexler, 1990, pp.53,55; Wilder-Smith, 1987, p.96). Every second for billions of years, all living systems have replicated themselves (Denton, 1998, p.147). This solution to all three problems is found in even the simplest of living things (Denton, 1985, p.337; Denton, 1998, p.147; Cairns-Smith, 1985, p.14). Cairns-Smith, notes that "the humble bacterium ... can reproduce" and so "must be an automatic factory containing something analogous to control tapes and automatic manufacturing equipment" and "there has also to be another kind of machinery that ... reprints them ... analogous to a Xerox machine or a tape copier" with all these things "instructed by appropriate bits of the Library tape (Cairns-Smith, 1985, p.14). Cairns-Smith also notes that the simple bacterium E. coli has a "message tape" whose "paper equivalent would be about 10 kilometres long," and with the minimum for a Von Neumann machine seems to be a paper tape equivalent about 2 kilometres long, since "no free-living organisms have been discovered with message tapes below '2 kilometres'" (Cairns-Smith, 1985, p.14). In being able to replicate itself, the living machine is unique in our experience (Blum, 1962, p.178G). The origin of life is therefore not the origin of a self-replicating molecule, but the origin of a self- replicating Von Neumann machine (Wilder-Smith, 1987, p.96). Dawkins acknowledges that natural selection cannot work unless there already in is existence a "complex ... DNA/protein replicating machine" (Dawkins, 1986, p.141). An existing machine that can replicate itself is difficult enough to imagine, but that such a machine could originate itself is baffling problem that no one has been able to formulate a solution in their imagination (Blum, 1962, p.178G). Which means that evolution's `blind watchmaker', in order to build the first Von Neumann machine, would have had to (amongst all the other things) write from scratch the equivalent of a computerised paper tape about 2 kilometres long! But the problem is that natural selection is based self-replicating machines being already in existence, so to invoke natural selection to explain the origin of self-replicating machines is putting the cart before the horse (Blum, 1962, pp.178I-178J; Dawkins, 1986, p.141). In view of this, Cairns-Smith, who is an origin of life theorist, asks, "Is it any wonder that Von Neumann himself ... found the origin of life to be utterly perplexing?" (Cairns-Smith, 1985, p.14; Blum, 1962, p.178G). Denton observes: "So efficient is the mechanism of information storage and so elegant the mechanism of duplication ... that it is hard to escape the feeling that the DNA molecule may be the one and only perfect solution to the twin problems of information storage and duplication for self-replicating automata" (Denton, 1985, pp.337- 338). Denton concludes that, "It is ... the fact that everywhere we look, to whatever depth we look, we find an elegance and ingenuity of an absolutely transcending quality, which so mitigates against the idea of chance" (Denton, 1985, p.342). Denton asks, "Is it really credible that random processes could have constructed a reality, the smallest element of which ... is complex beyond our own creative capacities ... which excels in every sense anything produced by the intelligence of man" and compared with which "even our most advanced artefacts appear clumsy," as that of "neolithic man would in the presence of twentieth-century technology" (Denton, 1985, p.342). Yet we are expected to believe the evolutionist claim that this was all brought about by "a chapter of accidents" (Sagan & Druyan, 1992, pp.63-64; Shaw, 1921, p.xxxii)!
"Beginning nearly half a century ago, long before there was any discipline called AL [Artificial Life], computer pioneer John von Neumann sought to investigate the question of life's origin by trying to design a self-reproducing automaton. This machine was to operate in a very simplified environment to see just what was involved in reproduction. ... Von Neumann in the late '40s and early '50s attempted to design such a system (called a cellular automaton) that could construct any automaton from the proper set of encoded instructions, so that it would make a copy of itself as a special case. But he died in 1957 before he could complete his design, and it was finished by his associate Arthur Burks (von Neumann, 1966). Because of its complexity -- some 300x500 chips for the memory control unit, about the same for the constructing unit, and an instruction "tape" of some 150,000 chips) -- the machine von Neumann designed was not built. Since von Neumann's time, selfreproducing automata have been greatly simplified. E. F. Codd (1968) reduced the number of states needed for each chip from 29 to 8. But Codd's automaton was also a "universal constructor" -able to reproduce any cellular automaton including itself. As a result, it was still about as complicated as a computer. ... Christopher Langton (1984) made the real break-through to simplicity by modifying one of the component parts of Codd's automaton and from it producing a really simple automaton (shown below) that will reproduce itself in 151 time-steps. It reproduces by extending its arm (bottom right) by six units, turning left, extending it six more units, turning left, extending six more, turning left a third time, extending six more, colliding with the arm near its beginning, breaking the connection between mother and daughter, and then making a new arm for each of the two automata. Langton's automaton, by design, will not construct other kinds of cellular automata as von Neumann's and Codd's would. His device consisted of some 10x15 chips, including an instruction tape of 33 chips, plus some 190 transition rules. Just a few years later, John Byl (1989a, b) simplified Langton's automaton further (see below) with an even smaller automaton that reproduced in just 25 time-steps. Byl's automaton consisted of an array of 12 chips -- of which 4 or 5 could be counted as the instruction tape -- and 43 transition rules. Most recently, Mark Ludwig (1993, pp. 107-108) has apparently carried this simplification to its limit with a miniscule automaton that reproduces in just 5 time-steps. This automaton consists of 4 chips, only one of which is the instruction "tape," and some 22 transition rules. It is interesting to note that the information contained in each of these selfreproducing automata may be divided into three parts: (1) the transition rules, (2) the geometry of the chips, and (3) the instruction tape. (1) The transition rules, which tell us how state succeeds state in each chip, somewhat resemble the physics or chemistry of the environment in the biological analogue. (2) The geometry of the automaton would correspond to the structure of a biological cell. (3) The instructions resemble the DNA. Thus these automata have a division of information which corresponds to that found in life as we know it on earth. In both cases self- reproduction depends not only on an instruction set, but also upon the structure of the reproducer and the nature of the physical realm in which it operates. For the von Neumann and Codd automata, since they are universal constructors, the size of the machine and its instructions are enormous! One could not seriously entertain a naturalistic origin of life if the original selfreproducing system had to have anything like this complexity. The smaller automata look much more promising, however. Perhaps a selfreproducing biochemical system at this level of complexity could have arisen by a chance assembly of parts. In a previous paper (Newman, 1988) I suggested that the random formation of something as complex as the Langton automaton (even with very generous assumptions) was out of the question in our whole universe in the 20 billion years since the big bang, as the probability of formation with all this space and time available is only 1 chance in 10^129. In response to Byl's proposed automaton, I found it necessary (Newman, 1990a) to retract some of the generosity given to Langton, but by doing so found that even Byl's automaton had only 1 chance in 10^69 of forming anywhere in our universe since the big bang. Ludwig's automaton looks so simple as to be a sure thing in a universe as vast and old as ours is. Indeed, by the assumptions used in doing my probability calculation for Byl's automaton, we would have a Ludwig automaton formed every 7 x 10^-15 seconds in our universe. However, an enormously favorable assumption is contained in this calculation - that all the carbon in the universe is tied up in 92-atom molecules which exchange material to try out new combinations as quickly as an atom can move the length of a molecule at room temperature. If, however, we calculate the expected fraction of carbon that would actually be found in 92-atom polymers throughout our universe, the expected time between formation of Ludwig automatons in our universe jumps to about 10^86 years! Thus it would still not be wise to put one's money on the random formation of selfreproduction even at this simple level. Besides the problem of formation time, the physics (transition rules) of these smaller automata was specially contrived to make the particular automaton work, and it is probably not good for anything else. Since the automata of Langton, Byl and Ludwig were not designed to be universal constructors, selfreproduction typically collapses for any mutation in the instructions. To avoid this, the constructing mechanism in any practical candidate for the first selfreproducer will have to be much more flexible so that it can continue to construct copies of itself while it changes. The physics of such automata could be made more general by going back toward the larger number of states used in von Neumann's automaton. ... Of course this would significantly increase the number of transition rules and the consequent complexity of his automaton. This, obviously, makes self-reproduction even less likely to have happened by chance. But it would also help alleviate the problem that these simpler automata don't have a big enough vocabulary in their genetic information systems to be able to do anything but a very specialized form of selfreproduction, and they have no way to expand this vocabulary which was designed in at the beginning. This problem seems to me a serious one for the evolution of growing levels of complexity in general." (Newman R.C., "Artificial Life and Cellular Automata," Access Research Network, March 15, 2000. http://www.arn.org/docs/newman/rn_artificiallife.htm)
"Self- replicating robots are no longer the stuff of science fiction. Scientists at the Cornell University in New York have created small robots that can build copies of themselves. Each robot consists of several 10-centimetre cubes, which have identical machinery, electromagnets to attach and detach to each other and a computer program for replication. The robots can bend and pick up and stack the cubes. "Although the machines we have created are still simple compared with biological self-reproduction, they demonstrate that mechanical self- reproduction is possible and not unique to biology," Hod Lipson said in a report in the science journal Nature .... He and his team believe the design principle could be used to make long term, self- repairing robots that could mend themselves and be used in hazardous situations and on space flights. The experimental robots, which do not do anything else except make copies of themselves, are powered through contacts on the surface of the table and transfer data through their faces. They self- replicate by using additional modules placed in special "feeding locations." The machines duplicate themselves by bending over and putting their top cube on the table. Then they bend again, pick up another cube, put it on top of the first and repeat the entire process. As the new robot begins to take shape it helps to build itself. "The four-module robot was able to construct a replica in 2.5 minutes by lifting and assembling cubes from the feeding locations," said Mr Lipson. .... " (US scientists create self-replicating robot," ABC/Reuters, May 12, 2005)
"Self-reproduction is central to biological life for long-term sustainability and evolutionary adaptation. Although these traits would also be desirable in many engineered systems, the principles of self- reproduction have not been exploited in machine design. Here we create simple machines that act as autonomous modular robots and are capable of physical self-reproduction using a set of cubes." (Zykov V. , Mytilinaios E., Adams B. & Lipson H., Robotics: Self-reproducing machines , Nature 435, 163-164 , 12 May 2005)
"Engineers in the US have created a machine out of intelligent cubes that can make copies of itself. They say it is a small step towards developing robots that can repair and replicate themselves in space or hazardous environments where it is difficult for humans to venture. Assistant Professor Hod Lipson [said] "Self- reproduction is central to biological life for long-term sustainability and evolutionary adaptation," ... The machine Lipson's team developed is made up of a set of modular cubes, called molecubes, which each contain the machinery and a computer program necessary for self-replication. The 10-centimetre cubes use electromagnets on their faces to selectively connect and disconnect from each other and they draw power through contacts on the surface of the table they sit on. Each cube is divided in half along its diagonal and this enables a robot made of a number of the cubes to bend and move its own, and other, cubes around. ... The robot bends around, moving its own cubes and new cubes 'fed' to it by the researchers. Because it is not possible for the original robot to reach across another robot of the same height, the new robot must assist in completing its own construction. ... "The design concept could be useful for long-term, self- sustaining robotic systems in emerging areas such as space exploration and operation in hazardous environments, where conventional approaches to maintenance are impractical."... Richard Willgoss ... says mechanical replication provides building blocks towards doing a lot of other things that biological systems do, albeit at a much larger scale. "If biology does it so well, why can't we do it too." Willgoss, who is working on a modular robotic arm, says intelligent modules can communicate with each other, as cells in the immune system do. He says such developments could lead to robotic systems that provide "tool kits" capable of, for example, making a vehicle one day and a bridge the next. The idea is that if a module breaks down the robot can repair it, or perhaps a whole entire new robot can be built. "If we can make robots that have distributed intelligence, we can perhaps give them a global request and they'll do the rest for us. It's very fanciful but you have to start somewhere," says Willgoss. ...While these self-replicating robots are 10 centimetres across, some scientists have discussed the idea of self-replicating robots the size of molecules. This has led to the nightmare scenario of self-replicating nano-robots, or nanobots, reducing the Earth to a mass of seething "grey goo". So do the new developments make this more likely? "The intelligence behind making that assembly could easily be taken down to the nano scale but the practicality of making the unit is a different matter," he says. "We've gone to the micro scale where we're making tiny little cogs in wheels on a substrate with integrated circuits but nanotech involves the atomic scale and that requires very specialised equipment to do that." (Salleh A., Intelligent robot copies itself, ABC, 12 May 2005)
"It has been the dream - and nightmare - of science fiction writeam of engineers has conjured up a robot that can reproduce itself. ..."Here we create siachines that act as autonomous modular robots and are capable to physical self-reproduction using a set of cubes." Modular cubes called "molecubes", each of which contains the machinery and computer program necessary for replication, are at the heart of the robot's ability to self-replicate. Electromagnets on each of the cubes' faces allow them to attach and detach themselves to another cube according to the computer's instructions. This allows a damaged robot to jettison defective cubes and replace them by working ones or for it to construct a separate robot from scratch by building a stack of individual cubes. When the newly-formed robot reaches a certain height it helps to finish off its own replication by adding the last molecubes to its own body. Professor Lipson said that although the robot they have designed would only work in a laboratory, it would - in theory - be possible to adapt the design to enable self- replication to take place in space or other hazardous environments. "Self- reproduction is an extreme case of self-repair from an engineering point of view," Professor Lipson said. ... The researchers were able to demonstrate a robot made from four modules that could build a replica of itself in two and a half minutes by lifting and assembling the cubes from a "feeding point" on the ground." (Connor S., Stuff of sci-fi nightmares? An army of robots that reproduce, The Independent, 12 May 2005)
"Mimicking reproduction in living organisms, researchers have built a simple self-replicating robot out of automated blocks. Machines that can copy themselves have been built before, but the earlier experiments were limited to two dimensions or confined to a track. Hod Lipson and his collaborators ... have designed modular cubes, called molecubes, that can assume a range of three-dimensional shapes. "People think of robots as durable metallic machines, and the only way to make them last longer is to make them more sturdy," Lipson said. Lipson and his colleagues are exploring a different paradigm, in which robots become more robust through self-repair. "Animals survive longer than robots because they can repair themselves," Lipson explained ... The new robots are simpler and less autonomous than biological organisms. But the scientists argue that self- replication is not a yes-or-no proposition, but rather a spectrum based on complexity and independence. ... The robots are composed of four-inch-wide cubes that attach and release each other with electromagnets. The cubes are cut in half along a diagonal plane, allowing the robot to swivel 90 degrees. Each module carries a microprocessor with the step-by-step instructions for replication. Sensors tell the robot when a new cube has been attached at one end, and power is supplied through floor plates. To help the robot make a copy of itself, the scientists placed new cubes at "feeding" stations. One of the challenges was designing modules that would not topple during motion. The initial robot relies on help from its unfinished "clone" in the construction process. In experiments, a four-cube-high robot copied itself in two and a half minutes. More complex shapes are possible in principle, but Lipson said that there are practical difficulties in making robots with more cubes. Currently, the robots have no practical use, but the research team said that it would be fairly easy to add other modules with grippers or a camera. Self-replicating robots could be valuable for space exploration and in hazardous environments, where they could take care of themselves without human help. One robot could even build out of its own components a new type of robot for a specific task, Lipson said." (Schirber M., New Robots Clone Themselves, Livescience, 11 May 2005)
"US researchers have devised a simple robot that can make copies of itself from spare parts. Writing in Nature, the robot's creators say their experiment shows the ability to reproduce is not unique to biology. Their long-term plan is to design robots made from hundreds or thousands of identical basic modules. These could repair themselves if parts fail, reconfigure themselves to better perform the task they have been set, or even to make extra helpers. So far, the robots, if they can be called that, consist of just three or four mobile cubes. Each unit comes with a small computer code carrying a blueprint for the layout of the robot, electrical contacts to let it communicate with its neighbours, and magnets to let them stick together. ... That offspring version can then make further copies. It is only a toy demonstration of the idea, but lead researcher Hod Lipson ... has bold plans for these intelligent modular machines." (Pease R., US robot builds copies of itself, BBC, 11 May, 2005. [See my comments] [top]
1. It is far more a problem than Hoyle's whirlwind in a junkyard assembling a Boeing 747 It is in fact far, far more of a problem than Fred Hoyle's analogy of a whirlwind blowing through a junkyard producing a fully assembled Boeing 747:
"The popular idea that life could have arisen spontaneously on Earth dates back to experiments that caught the public imagination earlier this century. If you stir up simple nonorganic molecules like water, ammonia, methane, carbon dioxide and hydrogen cyanide with almost any form of intense energy, ultraviolet light for instance, some of the molecules reassemble themselves into amino acids, a result demonstrated about thirty years ago by Stanley Miller and Harold Urey. The amino acids, the individual building blocks of proteins can therefore be produced by natural means. But this is far from proving that life could have evolved in this way. No one has shown that the correct arrangements of amino acids, like the orderings in enzymes, can be produced by this method. No evidence for this huge jump in complexity has ever been found, nor in my opinion will it be. Nevertheless, many scientists have made this leap-from the formation of individual amino acids to the random formation of whole chains of amino acids like enzymes-in spite of the obviously huge odds against such an event having ever taken place on the Earth, and this quite unjustified conclusion has stuck. In a popular lecture I once unflatteringly described the thinking of these scientists as a "junkyard mentality". As this reference became widely and not quite accurately quoted I will repeat it here. A junkyard contains all the bits and pieces of a Boeing 747, dismembered and in disarray. A whirlwind happens to blow through the yard. What is the chance that after its passage a fully assembled 747, ready to fly, will be found standing there? So small as to be negligible, even if a tornado were to blow through enough junkyards to fill the whole Universe." (Hoyle F., "The Intelligent Universe," Michael Joseph: London, 1983, pp.18-19)
The analogy would be of the whirlwind producing Boeing's 747 factory, but that it would have to also include all the factories that produce all the components from their raw materials that the Boeing 747 factory assembles together, because that is what the simplest free-living cell does. [top] 4. Information content of a cell
"Again, this is characteristic of all animal and plant cells. Each nucleus ... contains a digitally coded database larger, in information content, than all 30 volumes of the Encyclopaedia Britannica put together. And this figure is for each cell, not all the cells of a body put together. ... When you eat a steak, you are shredding the equivalent of more than 100 billion copies of the Encyclopaedia Britannica." (Dawkins R., "The Blind Watchmaker," [1986], Penguin: London, 1991, reprint, pp.17-18. Emphasis in original) [top]
5. The minimal cell 1. Minimum size of cell
"The American biochemist Harold Morowitz [Morowitz, 1966, pp.446-459] has speculated as to what might be the absolute minimum requirement for a completely self-replicating cell, deriving essential organic precursors, amino acids, sugars, etc. from its environment but autonomous in every other way in terms of current biochemistry. Such a cell would necessarily be bound by a cell membrane and the simplest feasible is probably the typical bilayered lipid membrane utilized by all existing cells. The synthesis of the fats of the cell membrane would require perhaps a minimum of five proteins. Energy would be required and some eight proteins might be needed for a very simplified form of energy metabolism. A minimum of ten proteins would be required for synthesis of the nucleotide building blocks of the DNA, and for DNA synthesis. Such a cell would also require a protein synthetic apparatus for the synthesis of its proteins. If this was along the lines of the usual ribosomal system, it would require a minimum of about eighty proteins. Such a minimal cell containing, say, three ribosomes, 4 mRNA molecules, a full complement of enzymes, a DNA molecule 100,000 nucleotides long and a cell membrane would be about 1000 (1 = 10-8 cm) in diameter. According to Morowitz: `This is the smallest hypothetical cell that we can envisage within the context of current biochemical thinking. It is almost certainly a lower limit, since we have allowed no control functions, no vitamin metabolism and extremely limited intermediary metabolism. Such a cell would be very vulnerable to environmental fluctuation. The smallest known bacterial cells, Morowitz continues, have: ... an average diameter of less than 3000. Since the minimum hypothetical cell has a diameter of over 1000 there is a limited gap in which to seek smaller cells. The minimal cell described above would contain sufficient DNA to code for about one hundred average sized proteins, which is close to the observed coding potential of the smallest known bacterial cells. It may be, therefore, that the tiniest of all known bacterial cells are very close to satisfying the minimum criteria for a fully autonomous cell system capable of independent replication. The complexity of the simplest known type of cell is so great that it is impossible to accept that such an object could have been thrown together suddenly by some kind of freakish, vastly improbable, event. Such an occurrence would be indistinguishable from a miracle." (Denton, 1985, pp.263-264)
"As far as the mycoplasma is concerned, we can safely assume that it is very close to the lower limit of size for an autonomously self-replicating cell. The biochemist Harold Morowitz has speculated as to what might be the absolute minimum requirement for a completely self-replicating cell deriving all essential organic precursors-amino acids, sugars, etc.-from its environment but autonomous in every other way in terms of our current under standing of biochemistry. [Morowitz, 1966, pp.446-459] Such a cell would necessarily be bound by a cell membrane and the simplest feasible would probably be the typical bilayered lipid membrane utilized by all existing cells on earth today. The synthesis of the fats of the cell membrane would require perhaps a minimum of five proteins. Energy would be required, and this might require a further eight proteins for a very simple form of energy metabolism. Altogether, probably a minimum of another hundred proteins would be required for DNA replication and protein synthesis. The size of such a cell, containing perhaps four mRNA molecules, a full complement of enzymes, a DNA molecule about 100,000 nucleotides long and bounded by a cell membrane, would be about one-tenth of a micron in diameter. Morowitz comments: `This is the smallest hypothetical cell that we can envisage within the context of current biochemical thinking. It is almost certainly a lower limit, since we have allowed no control functions, no vitamin metabolism and extremely limited intermediary metabolism.' [Ibid., p.456]" (Denton, 1998, p.309) [top]
2. Minimum number of genes
Studies have shown that the minimal number of genes necessary to specify a free-living organism that can survive by converting nutrients into energy, grow and reproduce, is about 300 (Adam & Sample, 2004). One of the simplest living organisms is a bacterium, Mycoplasma genitalium that has only about 470 genes (Begley, 1999, p.50; Adam & Sample, 2004). To find out which genes are the bare minimum essential for survival, scientists have systematically knocked out each gene of Mycoplasma genitalium to see if it can survive without it (Adam & Sample, 2004). About 215 genes have been found to be superfluous to Mycoplasma genitalium's survival in this way, leaving less than 300 genes required for life (Adam & Sample, 2004). But that does not mean that Mycoplasma genitalium can live without all these 215 genes, since the knockout experiments used Mycoplasma genitalium's with their full complement of 470 genes (Begley, 1999, p.50).
"Life Beyond the Minimal Set? It appears unlikely that the minimal gene set derived from the comparison of M. genitalium and H. influenzae can be significantly reduced without dramatically affecting functional systems that are essential for any extant cell, such as the translation or the replication machinery. As a matter of speculation, one can imagine, however, how the minimal set could be simplified to model a primitive cell, in which such essential systems might have been significantly simpler than they are in modern cells. ... It has to be kept in mind that not only reduction but also certain additions to the minimal gene [set] are likely to be required to produce a realistic model of a primitive cell. The most important of such additions may be a simple system for photo- or chemoautotrophy. It may become possible to glean the essential features of such systems from complete genome sequence of autotrophic organisms. Eventually, the backwards extrapolation from the minimal gene set may lead close to the origin of life itself." (Mushegian A.R. & Koonin E.V., "A minimal gene set for cellular life derived by comparison of complete bacterial genomes," Proceedings of the National Academy of Sciences, USA, Vol. 93, No. 19, September 17, 1996, pp.10268-10273. My emphasis. http://www.cs.huji.ac.il/csls2000/studies/compubio/Aviv10268.pdf)
"Haemophilus influenza contains about 1,700 genes; Mycoplasma genitalium contains only 470 genes, the smallest number yet discovered for any species. Arcady Mushegian and Eugene Koonin of the National Center for Biotechnology Information reasoned that any genes such diverse species hold in common are likely essential for basic cell function. That number adds up to 240. To cover certain enzyme functions critical for cell survival, they add 22 genes, for a total of 262, then they trim out 6 genes that appear redundant or specific to each bacteria's adaptation for feeding on its specific host. Their final figure, then, for the minimum genome to support cell function and reproduction is 256. (Mushegian A.R. & Koonin E.V., "A Minimal Gene Set for Cellular Life Derived by Comparison of Complete Bacterial Genomes," Proc. Natl. Acad. Sci. USA, Vol. 93, No. 19, September 17, 1996, pp.10268-10273). Referring to their calculation as preliminary, Mushegian and Koonin realize they may have overlooked some critical function(s) not covered by the 256 genes. Clearly, the bacteria do have to find and attach to suitable hosts, and some level of genetic redundancy appears essential for species' survival. When complete genome analysis for more species, including humans, becomes available in a few months, a more accurate estimate of life's minimal chemical complexity will also be available. But in the meantime, Mushegian and Koonin's work provides a ballpark figure for determining the magnitude of the `spontaneous generation' problem. Anyone proposing a naturalistic interpretation for life's origin must be able to explain how 256+ genes, plus all the other chemical components and structures for survival and reproduction put themselves together via mindless, purposeless, nonorganic processes." (Ross H.N., "Simplest Bacterium Not So Simple," Facts & Faith, Reasons To Believe: Pasadena CA, Vol. 10, No. 4, Fourth Quarter 1996, p.5. http://www.reasons.org/resources/faf/96q4faf/simple.shtml).
"Mycoplasma genitalium has the smallest genome of any organism that can be grown in pure culture. It has a minimal metabolism and little genomic redundancy. Consequently, its genome is expected to be a close approximation to the minimal set of genes needed to sustain bacterial life. Using global transposon mutagenesis, we isolated and characterized gene disruption mutants for 100 different nonessential protein- coding genes. None of the 43 RNA-coding genes were disrupted. Herein, we identify 382 of the 482 M. genitalium protein-coding genes as essential, plus five sets of disrupted genes that encode proteins with potentially redundant essential functions, such as phosphate transport. Genes encoding proteins of unknown function constitute 28% of the essential protein-coding genes set. Disruption of some genes accelerated M. genitalium growth." (Glass J.I., et al., "Essential genes of a minimal bacterium," Proceedings of the National Academy of Sciences, USA, Vol. 103, No. 2, January 10, 2006, pp.425-430)
"Oddly, this extensive comparison of genome sequences from widely divergent modern organisms has identified only about 60 genes that appear to be universal, and therefore probably date back to LUCA [Last Universal Common Ancestor]. That's nowhere near enough to sustain an organism, says Eugene Koonin, an evolutionary genomics researcher at the National Center for Biotechnology Information in Bethesda, Maryland. The majority of these genes are involved in translation, the process of converting the sequence of bases in DNA into the sequence of amino acids in protein. `On these genes alone, LUCA would go nowhere,' Koonin says. `There is nothing for a cell membrane, or for energy metabolism, or any synthetic capabilities. There should have been several times more genes.'" (Whitfield J., "Origins of life: Born in a watery commune," Nature, Vol. 427, No. 6976, 19 February 2004) [top]
See also Minimum number of genes necessary for life news articles (1999-2004) 3. Minimum number of proteins
"Dr. Harold J. Morowitz of Yale University has done extensive research for the National Aviation and Space Agency to discover the theoretical limits for the simplest free-living thing which could duplicate itself, or, technically, the minimal biological entity capable of autonomous self-replication. He took into consideration the minimum operating equipment needed and the space it would require. Also, attention was given to electrical properties and to the hazards of thermal motion. From these important studies, the conclusion is that the smallest such theoretical entity would require 239 or more individual protein molecules. This is not very much simpler than the smallest actually known autonomous living organism, which is the minuscule, bacteria-like Mycoplasma hominis H39. It has around 600 different kinds of proteins. From present scientific knowledge, there is no reason to believe that anything smaller ever existed. We will, however, use the lesser total of 239 protein molecules from Morowitz' theoretical minimal cell, which comprise 124 different kinds. It was noted earlier that there obviously can be no natural selection if there is no way to duplicate all of the necessary parts. In order to account for the left-handed phenomenon, chance alone, unaided by natural selection, would have to arrange at least one complete set of 239 proteins with all-left handed amino acids of the universal 20 kinds. There is reason to believe that all 20 of these were in use from the time of life's origin. ... Going back to the 1052 protein molecules that ever existed according to Dr. Eden, we may divide these into contiguous sets of 239 for such a minimal cell. There are 1049 such sets, rounded. By dividing this figure into 108350, and further dividing by a million to allow for overlapping sets, we arrive at the astounding conclusion that there is, on the average, one chance in 108395 that of all the proteins that ever existed on earth there would be a set of 239 together which were all left-handed, the minimum number required for the smallest theoretical cell." (Coppedge J.F., "Evolution: Possible or Impossible?," [1973], Zondervan, Grand Rapids MI, 1980, Seventh Printing, pp.71-73, 76) [top]
4. Minimum number of gene products (proteins, RNAs) The minimal, fully independent cell (that does not require its host or an experimenter to protect it and supply it with nutrients), would require ~1,500+ genes!:
"One way to explore the minimum complexity of independent life is to survey the microbial database for the smallest genome. .... The data indicate that the microbes possessing the smallest known genomes and capable of living independently in the environment are extremophilic archaea and eubacteria. ... These organisms also happen to represent what many scientists consider to be the oldest life on Earth. This crude estimate seems to suggest that, to exist independently, life requires a minimum genome size of about 1,500 to 1,900 gene products. (A gene product refers to proteins and functional RNAs, such as ribosomal and transfer RNA.) The late evolutionary biologist Colin Patterson acknowledges the 1,700 genes of Methanococcus are "perhaps close to the minimum necessary for independent life." [Patterson C., "Evolution," Comstock: Ithaca NY, Second edition, 1999, p.23] ... Given the relatively small sample of organisms currently available for assessing life's minimum complexity, investigators may well find the minimum requirement for independent life extends below 1,500 gene products. A newly discovered hyperthermophilic microbe helps establish a lower boundary. This organism, Nanoarchaeum equitans, lives as a parasite attached to the surface of its independently existing hyperthermophile host. Because it is a parasite, N. equitans exploits and depends upon its host cell's metabolism to exist. (In general, parasitic microbes have reduced genome sizes because of their reliance on host cell biochemistry.) Researchers have yet to estimate the N. equitans' genome size, but based on its amount of DNA, its genome size likely falls within the range of about 450 to 500 gene products. Even though incapable of independent existence, N. equitans yields insight into independent life's minimal complexity. Because this parasite thrives with a genome size of about 450 to 500 gene products, the minimum complexity for independent life must reside somewhere between about 500 and 1,500 gene products. So far, as scientists have continued their sequencing efforts, all microbial genomes that fall below 1,500 belong to parasites. Organisms capable of permanent independent existence require more gene products. A minimum genome size (for independent life) of 1,500 to 1,900 gene products comports with what the geochemical and fossil evidence reveals about the complexity of Earth's first life. Earliest life forms displayed metabolic complexity that included: o photosynthetic and chemoautotrophic processes o protein synthesis o the capacity to produce amino acids, nucleotides, fatty acids, and sugars o the machinery to reproduce Some 1,500 different gene products would seem the bare minimum to sustain this level of metabolic activity. For instance, the Methanococcus jannaschii genome (the first to be sequenced for the archaea domain) possesses about 1,738 gene products. This organism contains the enzymatic machinery for energy metabolism and for the biosynthesis and processing of sugars, nucleotides, amino acids, and fatty acids. In addition, the M. jannaschii genome can encode for repair systems, DNA replication, and the cell division apparatus. The genes for protein synthesis and secretion and the genes that specify the construction and activity of the cell membrane and envelope also belong as part of this organism's genome. The discovery of parasitic microbes with reduced genome sizes, like Mycoplasma genitalium, Mycoplasma pneumoniae, and Barrelia burgdorferi (with 470, 677, and 863 gene products, respectively), indicates that life exists, though not independently, with genome sizes made up of smaller than 1,500 genes. These microbes are not good model organisms for Earth's first life forms because they cannot exist independently. But they do have some relevance to life's beginning. These parasitic microbes help determine the barest minimal requirements for life, given that building block molecules (sugars, nucleotides, amino acids, and fatty acids as well as other nutrients) are readily available. Scientists from NIH have used the M. genitalium and H. influenzae genomes to estimate the minimum gene set needed for independent life. These researchers compared the two for genes with common function and reasoned that these constitute the minimum gene products necessary for life. This approach indicated that a set of 256 genes represents the lower limit on genome size needed for life to operate. Using a similar approach, an international team produced a slightly lower minimum estimate of 246. This group developed a universal set of proteins by comparing representatives from life's three domains-eukarya, archaea, and bacteria. In addition to theoretical estimates, researchers have also attempted to make experimental measurements of the minimum number of genes necessary for life. These approaches involve the mutation of randomly selected genes to identify those that are indispensable. One experiment performed on the bacterium Bacillus subtilis estimated the minimal gene set numbers between 254 and 450. A similar study with M. genitalium determined the minimum number of genes to fall between 265 and 350. Random mutations of the H. influenzae genome indicate that 478 genes are required for life in its bare minimal form. The genome of the extreme parasite Buchnera provides another means to determine the size of the minimal gene set. This parasite exists permanently inside aphid cells and has a remarkably tiny genome size. Scientists believe its gene set consists solely of those products essential for life. In contrast, M. genitalium's genome includes genes essential for life and genes that mediate host-parasite interactions. Presumably the genes disabled by mutation eliminated those involved in its host-parasite interactions. The genome size of the Buchnera species varies, with the smallest estimated to contain 396 gene products. Theoretical and experimental studies designed to discover the bare , minimum number of gene products necessary for life all show significant agreement. Life seems to require between 250 and 350 different proteins to carry out its most basic operations. That this bare form of life cannot survive long without a source of sugars, nucleotides, amino acids, and fatty acids is worth noting." (Rana F.R. & Ross H.N., "Origins of Life: Biblical And Evolutionary Models Face Off," Navpress: Colorado Springs CO, 2004 pp.161-163)
"In July 1995 the entire DNA sequence of the bacterium Haemophilus influenzae, 1.8 million base- pairs, was elucidated, followed three months later by the sequence of a second parasitic bacterium. In April 1996 the complete sequence (12 million base-pairs) of yeast was announced, and in August 1996 the first complete sequence of a free-living bacterium, Methanococcus, which has 1.7 million base- pairs and about 1700 genes, perhaps close to the minimum necessary for independent life." (Patterson C., "Evolution," [1978], Cornell University Press: Ithaca NY, Second edition, 1999, p.23) [top]
6. The first cell was irreducibly complex

The bottom line is that what is IC is Darwin's definition: a "complex organ [or structure] ... which could not possibly have been formed by numerous, successive, slight modifications":

"If it could be demonstrated that any complex organ existed which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down." (Darwin C.R., "The Origin of Species by Means of Natural Selection," [1872], Everyman's Library, J.M. Dent & Sons: London, 6th Edition, 1928, reprint, p.170)

Dawkins accepts this Darwin's definition of IC:

"Darwin wrote (in The Origin of Species): `If it could be demonstrated that any complex organ existed which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down.' [Darwin C.R., "The Origin of Species by Means of Natural Selection," (1872), Everyman's Library, J.M. Dent & Sons: London, 6th Edition, 1928, reprint, p.170] One hundred and twenty five years on, we know a lot more about animals and plants than Darwin did, and still not a single case is known to me of a complex organ that could not have been formed by numerous successive slight modifications. I do not believe that such a case will ever be found. If it is - it'll have to be a really complex organ, and, as we'll see in later chapters, you have to be sophisticated about what you mean by 'slight' - I shall cease to believe in Darwinism." (Dawkins R., "The Blind Watchmaker," [1986], Penguin: London, 1991, reprint, p.91. Emphasis in original)

even though he tries to weasel out of it by adding in the qualifiers "really" before "complex organ" and "sophisticated" before "slight". But if the first living organism with a minimum of ~256+ genes and ~239+ proteins is not "a really complex organ" then what is? And no matter how "sophisticated [the meaning of] ... 'slight'" (without nullifying it altogether) it must mean getting from zero (0) genes and proteins to 256+ genes and ~239+ proteins by "numerous successive ... [small] modifications."

Dawkins himself has defined what "slight" means in this context, namely 1) the difference between" a complex organ/structure "and its immediate predecessor X is sufficiently small, i.e. "sufficiently close to one another in the space of all possible structures"; 2) "could plausibly have arisen, directly by a single change"; 3) "a continuous series of Xs connecting the" complex organ/structure " ... to ... no" complex organ/structure "at all"; :4) "provided only that" there has been "a sufficiently large series of Xs"; in 5) "the available time .... for there can be only one X per generation":

"1. Could the human eye have arisen directly from no eye at all, in single step? 2. Could the human eye have arisen directly from something slightly different from itself, something that we may call X? The answer to Question 1 is clearly a decisive no. The odds against a `yes' answer for questions like Question 1 are many billions of times greater than the number of atoms in the universe. It would need a gigantic and vanishingly improbable leap across genetic hyperspace. The answer to Question 2 is equally clearly yes, provided only that the difference between the modern eye and its immediate predecessor X is sufficiently small. Provided, in other words, that they are sufficiently close to one another in the space of all possible structures. If the answer to Question 2 for any particular degree of difference is no, all we have to do is repeat the question for a smaller degree of difference. Carry on doing this until we find a degree of difference sufficiently small to give us a 'yes' answer to Question 2. X is defined as something very like a human eye, sufficiently similar that the human eye could plausibly have arisen by a single alteration in X. If you have a mental picture of X and you find it implausible that the human eye could have arisen directly from it, this simply means that you have chosen the wrong X. Make your mental picture of X progressively more likeprogressively mor a human eye, until you find an X that you do find plausible as an immediate predecessor to the human eye. There has to be one for you, even if your idea of what is plausible may be more, or less, cautious than mine! Now, having found an X such that the answer to Question 2 is yes, we apply the same question to X itself. By the same reasoning we must conclude that X could plausibly have arisen, directly by a single change, from something slightly different again, which we may call X'. Obviously we can then trace X' back to something else slightly different from it, X'', and so on. By interposing a large enough series of Xs, we can derive the human eye from something not slightly different from itself but very different from itself. We can 'walk' a large distance across 'animal space', and our move will be plausible provided we take small-enough steps. We are now in a position to answer a third question. 3. Is there a continuous series of Xs connecting the modern human eye to a state with no eye at all? It seems to me clear that the answer has to be yes, provided only that we allow ourselves a sufficiently large series of Xs. You might feel that 1,000 Xs is ample, but if you need more steps to make the total transition plausible in your mind, simply allow Yourself to assume 10,000 Xs. And if 10,000 is not enough for you, allow yourself 100,000, and so on. Obviously the available time imposes an upper ceiling on this game, for there can be only one X per generation. In practice the question therefore resolves itself into: Has there been enough time for enough successive generations? We can't give a precise answer to the number of generations that would be necessary. What we do know is that geological time is awfully long. Just to give you an idea of the order of magnitude we are talking about, the number of generations that separate us from our earliest ancestors is certainly measured in the thousands of millions. Given, say, a hundred million Xs, we should be able to construct a plausible series of tiny gradations linking a human eye to just about anything!" (Dawkins R., "The Blind Watchmaker," [1986], Penguin: London, 1991, reprint, pp.77-78. Emphasis in original)

So how many single "generations" of Xs are needed to get from 0 genes and 0 proteins to the minimum living self-reproducing organism of ~256+ genes and ~239 proteins? A minimum would presumably be (assuming there was a constant supply of pure gene and left-handed protein building blocks on the prebiotic Earth, or wherever) conservatively of the order of ~4256 = ~10154 genes first, or ~20239 = 10311 proteins first; or ~4256 * ~20239 = ~10154 * 311 = ~1047925 genes and proteins independently, *generations*. Evolutionists can take their pick or suggest their own number of generations!

The time available is probably not a problem, bearing in mind it was conservatively about ~4.0 - 3.5 = ~0.5 billion ~108.7 years between the Earth cooling down from its original molten state and after the Late Heavy Bombardment to the evidence of first life on Earth. Since there is 365 * 24 * 60 * 60 = 31,536,000 = ~107.5 seconds in a year (assuming that the years and days were the same then, when they were much shorter) That is 108.7 * 107.5 = 1016.2 seconds available. So at an average rate of 1 nucleotide every 1016.2/105.6 = 1010.6 seconds = 1010.6/107.5 = 10-0.15 years = 54.75 days or 1 protein every 1016.2/105.5 = 1010.7 seconds = 1010.7/108.7 = 10-0.17 years = ~ 62 days, 239 nucleotides would take only 239*54.75 = 13085.25 days = 35.85 years; and 256 proteins only 256 * ~62 = ~15872 days = ~ 43 years. What the real problems are: 1) a `primordial soup' of pure building blocks continuously available for the entire time; 2) a mechanism other than chance, to cause the building blocks to spontaneously assemble; and 3) not spontaneously disassemble! See my CED message #13192 [top]

7. Assembly of first cell was fantastically improbable
"The possibility of a living cell coming together in one shot is immeasurably less plausible than the spontaneous assembly of a Boeing 747-if degrees of impossibility are to be envisaged. ... A Boeing 747 is built piecemeal in a very large number of steps. Raw materials me first refined or synthesized and worked into a multitude of separate parts. These are then joined, in modular fashion, to make the engines, the body and wings, the flaps, the landing gear, the electronic circuits, and all the other parts of the aircraft. These various parts are then brought together for final assembly. The steps in the construction of a living cell are different, but the principle is the same. Because of the high complexity of the final product, there must, by necessity, be a very large number of steps, often modular in nature. This consideration completely alters the probability assessment. We are being dealt thirteen spades not once but thousands of times in succession! This is utterly impossible, unless the deck is doctored. What this doctoring implies with respect to the assembly of the first cell is that most of the steps involved must have had a very high likelihood of taking place under the prevailing conditions. Make them even moderately improbable and the process must abort, however many times it is initiated, because of the very number of successive steps involved." (de Duve, 1995, pp.8-9. Emphasis in original) [top]

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