Editor’s note: As an alternative to what you are getting pretty much everywhere else in the media at the moment, Evolution News is proud to offer inspiration, pointing to purpose and meaning in life. The profoundest mystery and thus the deepest inspiration is life itself. Discovery Institute Press has just published a greatly expanded edition of the 1984 classic of intelligent design science literature, The Mystery of Life’s Origin. Below is the original Foreword to the book by San Francisco State University biologist Dean Kenyon.
The Mystery of Life’s Origin presents an extraordinary new analysis of an age-old question: How did life start on Earth? The authors deal forthrightly and brilliantly with the major problems confronting scientists today in their search for life’s origins. They understand the impasse in current laboratory and theoretical research and suggest a way around it. Their arguments are cogent, original, and compelling. This book is sure to stimulate much animated discussion among scientists and laymen. It is very likely that research on life’s origins will move in somewhat different directions once the professionals have read this important work.
An Important Work
The modern experimental study of the origin of the first life on Earth is now entering its fourth decade, if we date the inception of this field of research to Stanley Miller’s pioneering work in the early 1950s. Since Miller’s identification of several (racemic) protein-forming amino acids in his electric discharge apparatus, numerous follow-up studies have been conducted. Conforming in varying degrees to the requirements of the so-called “simulation paradigm,” these experiments have yielded detectable amounts of most of the major kinds of biochemical substance as well as a variety of organic microscopic structures suggested to be similar to the historical precursors of the first living cells.
This program of research can be regarded as a natural extension of Darwin’s evolutionary views of the last century. The goal of the work is to find plausible uniformitarian mechanisms for the gradual spontaneous generation of living matter from relatively simple molecules thought to have been abundant on the surface of the primitive Earth.
In Search of a Naturalistic Explanation
The experimental results to date have apparently convinced many scientists that a naturalistic explanation for the origin of life will be found, but there are significant reasons for doubt. In the years since the publication of Biochemical Predestination I have been increasingly struck by a peculiar feature of many of the published experiments in the field. I am not referring to those studies conducted more or less along the lines of Miller’s original work, although there are firm grounds for criticizing those studies as well. I am referring to those experiments designed to elucidate possible pathways of prebiotic synthesis of certain organic substances of biologic interest, such as purines and pyrimidines, or polypeptides.
In most cases the experimental conditions in such studies have been so artificially simplified as to have virtually no bearing on any actual processes that might have taken place on the primitive Earth. For example, if one wishes to find a possible prebiotic mechanism of condensation of free amino acids to polypeptides, it is not likely that sugars or aldehydes would be added to the reaction mixture. And yet, how likely is it that amino acids (or any other presumed precursor substance) occurred anywhere on the primitive Earth free from contamination substances, either in solution or the solid state? The difficulty is that if sugars or aldehydes were also present polypeptides would not form. Instead an interfering cross-reaction would occur between amino acids and sugars to give complex, insoluble polymeric material of very dubious relevance to chemical evolution. This problem of potentially interfering cross-reactions has been largely neglected in much of the published work on the chemical origins of life. The possible implications of such an omission merit careful study.
My Growing Uneasiness
Other aspects of origin-of-life research have contributed to my growing uneasiness about the theory of chemical evolution. One of these is the enormous gap between the most complex “protocell” model systems produced in the laboratory and the simplest living cells. Anyone familiar with the ultrastructural and biochemical complexity of the genus Mycoplasma, for example, should have serious doubts about the relevance of any of the various laboratory “protocols” to the actual historical origin of cells. In my view, the possibility of closing this gap by laboratory simulation of chemical events likely to have occurred on the primitive Earth is extremely remote.
Another intractable problem concerns the spontaneous origin of the optical isomer preferences found universally in living matter (e.g., L- rather than D-amino acids in proteins, D- rather than L-sugars in nucleic acids). After all the prodigious effort that has gone into attempts to solve this great question over the years, we are really no nearer to a solution today than we were thirty years ago.
Finally, in this brief summary of the reasons for my growing doubts that life on Earth could have begun spontaneously by purely chemical and physical means, there is the problem of the origin of genetic, i.e., biologically relevant, information in biopolymers. No experimental system yet devised has provided the slightest clue as to how biologically meaningful sequences of subunits might have originated in prebiotic polynucleotides or polypeptides. Evidence for some degree of spontaneous sequence ordering has been published, but there is no indication whatsoever that the non-randomness is biologically significant. Until such evidence is forthcoming one certainly cannot claim that the possibility of a naturalistic origin of life has been demonstrated.
In view of these and other vexing problems in origin-of-life research, there has been a need for some years now for a detailed, systematic analysis of all major aspects of the field. It is time to re-examine the foundations of this research in such a way that all the salient lines of criticism are simultaneously kept in view. The Mystery of Life’s Origin admirably fills this need. The authors have addressed nearly all the problems enumerated above and several other important ones as well. They believe, and I now concur, that there is a fundamental flaw in all current theories of the chemical origins of life. Although the tone of the book is critical, the authors have written it in the positive hope that their analysis will help us find a better theory of origins. Such an approach is, of course, entirely consistent with the manner in which scientific advances have occurred in the past.
One of the uniquely valuable features of the book is its discussion (Chap. 6) of the relative geochemical plausibilities of the various types of simulation experiments reported in the literature. To my knowledge this is the first systematic attempt to devise formal criteria for acceptable degrees of interference by the investigator in such experiments. Another especially helpful feature is the detailed discussion of the implications of thermodynamics (Chaps. 7, 8, and 9) for the origin-of-life problem. This important topic is either omitted entirely or is treated superficially in most other books on the chemical origins of life. The authors might have included a more detailed discussion of the problem of optical isomer preferences, but this deficiency detracts in only a minor way from the overall strength of their argument.
What Scientists Fear
If the authors’ criticisms are valid, one might ask, why have they not been recognized or stressed by workers in the field? I suspect that part of the answer is that many scientists would hesitate to accept the authors’ conclusion that it is fundamentally implausible that unassisted matter and energy organized themselves into living systems. Perhaps these scientists fear that acceptance of this conclusion would open the door to the possibility (or the necessity) of a supernatural origin of life. Faced with this prospect many investigators would prefer to continue in their search for a naturalistic explanation of the origin of life along the lines marked out over the last few decades, in spite of the many serious difficulties of which we are now aware. Perhaps the fallacy of scientism is more wide- spread than we like to think.
One’s presuppositions about the origin of life, and especially the assumption that this problem will ultimately yield to a persistent application of current methodology, can certainly influence which lines of evidence and argument one chooses to stress, and which are played down or avoided altogether. What the authors have done is to place before us essentially all the pertinent lines of criticism in one continuous statement and to invite us to face them squarely.
All scientists interested in the origin-of-life problem would do well to study this book carefully and to evaluate their own work in the light of its arguments.
Read the rest of The Mystery of Life’s Origin: The Continuing Controversy, from Discovery Institute Press.
Photo: Dean H. Kenyon, in “On the Origin of Life: An Interview with Dr. Dean Kenyon,” via Access Research Network (screenshot).