1. Background

The Discovery Institute (DI) seeks to promote "intelligent design", defined on one of its web sites as follows:

["Intelligent design"] refers to a scientific research program as well as a community of scientists, philosophers and other scholars who seek evidence of design in nature. Through the study and analysis of a system's components, a design theorist is able to determine whether various natural structures are the product of chance, natural law, ["intelligent design"], or some combination thereof. … In nature, design theorists cite information[-]rich systems like the genetic code, irreducibly complex systems like the bacterial flagellum, and the fine-tuning of the laws of physics as evidence of ["intelligent design"](http://www.reviewevolution.com/whatIsIntelligentDesign.php).

And it is "intelligent design" that creationist organizations such as Science Excellence for All Ohioans (SEAO) are lobbying OBE to add to the proposed state science standards, over the protests of the 45-member writing committee. (For SEAO's proposals, see http://www.seao.org; for the writing committee's objections, see "Curriculum team backs evolution", Cleveland Plain Dealer, 2002 Mar 16.)

As Lawrence Krauss of Case Western Reserve University reported at the March 11, 2002, panel discussion in Columbus, there is no published work in the peer-reviewed scientific literature supporting "intelligent design" (see "State board studying theories on start of life", Cleveland Plain Dealer, 2002 Mar 12, and Gilchrist 1997). Peer-review of a scientific publication is an assessment of the work's scientific merit by experts having knowledge of the research area equal to that of the author. Peer review is essentially a form of quality control in the modern scientific world. The fact that there is no published work in the peer-reviewed scientific literature that supports "intelligent design" contradicts the DI's claim that "intelligent design" is a scientific theory.

But clearly many of the items in the "Bibliography of Supplementary Resources for Ohio Science Education" provided by Jonathan Wells and Stephen C Meyer of the Discovery Institute to the Ohio Board of Education were published in the peer-reviewed scientific literature (the publications listed in the Bibliography - though not the Discovery Institute's summaries of them - are listed on p 15). The 44 publications listed in the Bibliography are indeed legitimate and valuable contributions to the scientific literature. The material provided to the OBE was prefaced with the following explanation:

The publications represent dissenting viewpoints that challenge one or another aspect of neo-Darwinism (the prevailing theory of evolution taught in biology textbooks), discuss problems that evolutionary theory faces, or suggest important new lines of evidence that biology must consider when explaining origins.

Because the representatives of the Discovery Institute who appeared at the March 11 meeting - Jonathan Wells and Stephen C Meyer - were widely touted as promoters of "intelligent design", it would have been reasonable for the OBE to assume that "intelligent design" could be found among the "dissenting viewpoints" included in the Bibliography. But it is not.

NCSE sent a questionnaire to the authors of every publication listed in the Bibliography, asking them whether they considered their work to provide scientific evidence for "intelligent design". (In the case of publications with multiple authors, NCSE sent a questionnaire to at least one of the authors.) None of the 26 respondents (representing 34 of the 44 publications in the Bibliography) agreed that their cited work provided any support for "intelligent design"; many were indignant at the suggestion. For example, Douglas H Erwin (author of item 8 in the Bibliography), answered:

Of course not - ["intelligent design"] is a non sequitur, nothing but a fundamentally flawed attempt to promote creationism under a different guise. Nothing in this paper or any of my other work provides the slightest scintilla of support for "intelligent design". To argue that it does requires a deliberate and pernicious misreading of the papers.

(Quotations from the authors of the publications are reproduced, with permission, from their responses to NCSE's questionnaire. The questionnaire itself is reproduced on p 26, "NCSE's Questionnaire to Authors".) Several respondents even went so far as to say that their work constituted scientific evidence against "intelligent design".

Similarly, on the basis of the explanation prefaced to the Bibliography, it would have been reasonable for the OBE to assume that the publications included in the Bibliography challenged evolution. But they do not. None of the respondents to NCSE's questionnaire considered their work to provide scientific evidence against evolution. David M Williams (coauthor of item 18), for example, simply remarked, "No, certainly not. How could it possibly?" Almost all of the respondents emphasized that their work provided scientific evidence for evolution. Kenneth Weiss (author of item 21), for example, remarked, "I state clearly that evolution is beyond dispute based on all the evidence I am aware of."

Shortly after NCSE began to send its questionnaire to the authors of the publications listed in the DI's Bibliography, the following disclaimer to its Bibliography appeared on the DI web site:

The publications are not presented either as support for the theory of intelligent design, or as indicating that the authors cited doubt evolution. Discovery Institute has made every effort to ensure that the annotated summaries accurately reflect the central arguments of the publications (from http://www.discovery.org/viewDB/index.php3?command=view&id=1127&program=CRSC%20Responses, emphasis in original).

Should not the Discovery Institute have issued such a disclaimer in the first place?

Moreover, in light of Stephen C Meyer's declaration ("Teach the controversy on origins", Cincinnati Enquirer, 2002 Mar 30) that the Bibliography contains publications "that raise significant challenges to key tenets of Darwinian evolution" - a declaration that significantly postdates the disclaimer - the sincerity of the disclaimer may be doubted.

2. What is the real significance of the publications in the Bibliography?

Within the Bibliography, the publications are divided into 3 categories: Questions of Pattern, Questions of Process, and Questions about the Central Issue: the Origin and Nature of Biological Complexity. In each of these categories, there are two issues to address: what the significance of the publications really is, and what the Discovery Institute would have people believe it is. The two are rarely the same.

a. Questions of pattern

Phylogenetics is the field of biology that attempts to determine the evolutionary relationships among organisms (phylogenies). Molecular phylogenetics is based on data from genes and other macromolecules (taken from mitochondria, ribosomes, or nuclear DNA). When molecular phylogenetics was first introduced, it was widely believed to be more reliable than morphological phylogenetics, which is based on anatomical characteristics, but more recent research suggests that molecular phylogenetics is subject to difficulties of its own. What the publications cited in the Bibliography reflect is the current lively controversy in the scientific community about phylogenetic methodology and how to reconcile conflicts when the results of different methods disagree.

The Discovery Institute's selection of publications in the Questions of Pattern section is idiosyncratic. Over 1600 papers on molecular phylogeny have been published in the last 10 years; why did the Discovery Institute select these particular 22? There is no unifying subject of the publications: they deal variously with mammals, insects, bacteria, and metazoans in general. And several of the publications are out of date; for example, Douglas H Erwin (author of item 8) remarks:

Citing [this] paper from 1994 is decidedly poor scholarship, however, given how fast this field has moved. The rapid advances in comparative developmental biology have rendered much of this pretty outdated. We now have a very well substantiated metazoan phylogeny, at least in general outline, allowing some of the tests suggested at the end of the cited passage. Moreover, comparative developmental studies have only served to emphasize the fundamental unity of bilaterian animals.

There are also papers from 1993 and 1991, which are practically ancient by the standards of the fast-moving field of molecular phylogeny.

The only point of similarity among the publications in the Questions of Pattern section appears to be that there are passages in them that, if taken out of context or otherwise misrepresented, seem to express doubt about phylogeny in general. But for the DI to insinuate that scientific debates about how to determine which organisms are related to which are debates about whether organisms are related is misleading. As Peter J Lockhart (coauthor of item 13) carefully explains, in responding to the Discovery Institute's summary of his work:

I don't think it is a good representation of our work - our work does not present "a classic challenge to evolutionary analysis". In our paper we point out that technically it is a hard problem to reconstruct the phylogeny of corbiculate bees regardless of whether you use morphological or molecular data (the reason for this concerns the pattern of radiation - four different lineages diverged in a short period of time a long time ago - given this pattern it is not surprising that different data types might suggest different phylogenies). In our article we do not say that interpretation of the molecular data is right and that interpretation of the morphological data is wrong (or vice versa). Instead we make some suggestions which we believe will help resolve why the different data types suggest different conclusions - we suggest that the bee morphologists relook at the interpretation of some of their data and we also encourage the molecular biologists to determine some additional data which would help test their hypotheses - we suggest that if these things are done then there should be a resolution to the controversy over which phylogeny is correct. We do not doubt that there is a phylogeny - in contrast, the statement by the Discovery Institute suggests that the bee controversy is evidence for absence of phylogeny. No scientist involved in the corbiculate bee debate has ever suggested this to my knowledge.

Kenneth Weiss's article "We hold these truths to be self-evident" (item 21) is the odd article out in the section on Questions of Pattern. Weiss was not discussing phylogeny; the DI apparently included it just in order to quote him as saying, "It is healthy to be skeptical even of truths we hold to be self-evident, and to ask: suppose it isn't true - what would follow? Do we need a theory of evolutionary biology?" Weiss told NCSE, "This is misrepresenting the fuller context. For example, the last question that is quoted was followed by my asking what would be the minimal essential elements of such a theory that biologists would insist on." And although the DI parenthetically added, "Please note that in his footnotes, Weiss is highly skeptical of creationism, and endorses what he calls 'the fact' of evolution", Weiss responded, "The Discovery Institute does not give an honest sense of the clarity that I put in that disclaimer: 'Given the spate of recent anti-evolutionary books, I feel compelled to make the statement here that nothing in this column in any way questions the fact of evolution, nor in any way supports creationist accounts (one cannot call them "explanations") for the diversity of life.'"

b. Questions of process

The bulk of the publications in the Questions of Process section of the Bibliography belong to the newly emerging field of evolutionary developmental biology ("evo-devo"), which has provided one of the most powerful models for explaining evolutionary novelty. As Corey S Goodman and Bridget C Coughlin (2000) write,

Once seen as distinct, yet complementary[,] disciplines, developmental biology and evolutionary studies have recently merged into an exciting and fruitful relationship. The official union occurred in 1999 when evolutionary developmental biology, or "evo-devo", was granted its own division in the Society for Integrative and Comparative Biology (SICB). It was natural for evolutionary biologists and developmental biologists to find common ground. Evolutionary biologists seek to understand how organisms evolve and change their shape and form. The roots of these changes are found in the developmental mechanisms that control body shape and form. Developmental biologists try to understand how alterations in gene expression and function lead to changes in body shape and pattern. So although SICB only recently validated evo-devo as an independent research area, evo-devo really started over a decade ago when biologists began using an individual organism's developmental gene expression patterns to explain how groups of organisms evolved.

The emergence of evo-devo is anything but a challenge to evolution.

As with the publications in the Question of Pattern section, the publications in the Questions of Process section seem to have been selected only because they provide passages that, if taken out of context or otherwise misrepresented, seem to express doubt about the neo-Darwinian synthesis or macroevolution in general. What must be understood is that although these debates about the details of evo-devo and the mechanisms of macroevolution are legitimate, they in no way affect the presentation of evolution at the high school level, which is simply not presented in enough detail for these highly technical debates to be relevant.

And as with the publications in the Questions of Pattern section, the authors themselves reject the Discovery Institute's misinterpretation of their work. Thus, for example, Günther P Wagner (coauthor of item 31 and author of item 32), wrote:

In no way does my work represent an attack on the theory of descent with modification, that is, the plain fact of evolution, or even the fundamental insights of the neo-Darwinian theory of evolution. It is intended as an attempt to extend the explanatory reach of Darwinian evolutionary thinking by eliminating some technical limitations that result from the mathematical language currently used to model evolutionary processes. All that work agrees with and is based on the fact that evolution proceeds by the spontaneous generation of genetic variation and the fixation of these variations by selection and/or drift. The points of my papers are narrow technical ones and in no way weaken the fundamental insights of Darwinian evolutionary thinking. They do, however, challenge some of the more speculative extensions of this theory, like the idea that everything is possible with more or less equal probability. But this does not affect the fundamentals of the neo-Dar-winian theory of evolution.

Scott F Gilbert (coauthor of items 25 and 27) wrote:

My research on turtles and my research into evolutionary developmental biology is fully within Darwinian parameters. My gripe has been that neo-Darwinism has supposed that population genetics was the only genetics needed to explain Darwinian evolution. I claim that developmental genetics is also needed. So my research has been to include developmental genetics into the Darwinian mix.

And Douglas L Erwin (author of item 24) told NCSE:

While the article considers the relationship between micro- and macro- evolution, the Discovery Institute is inaccurate in saying that I am challenging the standard view of evolution. The treatment of macroevolution in that paper is an extension, but by no means a challenge. Further, although more work may be needed to fully understand macroevolutionary events, there is no evidence that requires, or even suggests, a role for so-called "intelligent design".

Although Eörs Szathmáry's article (item 44) was not included in the section on Questions of Process, his comments are relevant here. Answering the DI's claim that the publications in the Bibliography "represent dissenting viewpoints that challenge one or another aspect of neo-Darwinism (the prevailing theory of evolution taught in biology textbooks)", Szathmáry replied, "This depends very much on how you define neo-Darwinism. First, like science in general, it is developing. Second, there are cutting-edge and pedestrian conceptualizations of neo-Darwinism. My coauthor on two books, John Maynard Smith, would be regarded by many as an arch- neo-Darwinist. Yet, for those, The Major Transitions in Evolution [by Maynard Smith and Szathmáry] came as a bit of a shock... But that's only because of an outdated idea of how a neo-Darwinist should approach evolution..."

c. Questions about the central issue: The origin and nature of biological complexity

According to the Discovery Institute, the publications in the Questions about the Central Issue section "concerns the origin of what makes organisms distinctively what they are: the source of the specified complexity of biological information." It is wholly unclear what the DI intends here; "specified complexity" and "biological information" are not terms with a definite meaning within the scientific community. (This is not to deny that these terms occasionally appear in the biological literature. But they have no consistent, well-established, definite meaning there.) They are, however, prominent terms in the philosophical and theological writings of Discovery Institute Senior Fellow William A Dembski, author of Intelligent Design: The Bridge Between Science and Theology (1999), which may explain their appearance in the Bibliography.

The publications are a hodgepodge of work from various disciplines (biomimetics, artificial life and artificial intelligence, the origin of life, investigations into the minimal genome) with little in common - except, of course, that they contain passages that, if taken out of context or otherwise misrepresented, seem to express doubt about evolution. Again, the authors themselves reject the Discovery Institute's misinterpretation of their work.

Philip Ball told NCSE that his paper on biomimetics (item 33) is in fact evidence for "the effectiveness of evolution in fine-tuning the properties and features of natural systems." Rodney Brooks (author of item 34) complained that "they have selectively quoted just parts of what I wrote in order to distort completely what I said in the article." Leslie E Orgel (author of item 43) wrote,

The paper is intended to support a conventional Darwinian form of evolution based on reproduction, selection, and mutation of polymeric molecules and to argue against a different form of evolution based on self-organizing cycles of chemical reaction. Supporters of both sides of the argument take evolution for granted, as do all competent biologists, but they disagree about important details. … it would be appropriate to point out that all scientists carrying out experimental work on the origins of life believe that one form or another of Darwinism can adequately explain the origin of life on the earth without any recourse to "intelligent design".

3. Is the Bibliography reliable?

As the preceding discussion indicates, the Discovery Institute's view of the significance of the publications in its Bibliography was uniformly rejected by the authors themselves. But was the DI able to summarize the arguments of the publications in its Bibliography correctly? No. More than half of the respondents to NCSE's questionnaire considered the summaries in the Bibliography to be inaccurate and tendentious. Here is a sampling of their responses.

Eugene V Koonin (coauthor of item 12): "…the conclusion that this is 'a hypothesis quite unexpected on neo-Darwinian (common ancestry) assumptions' is (i) not taken from our paper and (ii) not at all compatible with the data or ideas presented in the paper."

David P Mindell (coauthor of item 14): "The words enclosed in quotation marks are accurate. However, the quotes are entirely misinterpreted and taken out of context. This is just as the scientific community, and at least some of the public, has come to expect from the Discovery Institute."

Paul Morris (coauthor of item 15):

The quotations are accurate; their assembly is a little misleading (the context of the first quote is a discussion of similar amino acids assembled by different synthesis pathways, where the evidence for homology lies in the synthesis pathways rather than in the amino acids, while the second quote is in the context of discussion of protein sequence similarity). The implications, particularly that molecular data are unable to reconstruct the history of life, are complete distortions of what we said.

David M Williams (coauthor of item 18): "The short answer to your question, 'Do you consider this accurate?', is no."

Michael K Richardson (coauthor of item 19):

Partly accurate and partly ambiguous. The creationists have taken a very complicated argument and extracted from it the bits and pieces that fit their world view. In particular, I have some problems with the following statement: "There is no single stage of embryogenesis in vertebrates where all forms are similar". In fact, there are strong resemblances between vertebrate embryos at various times in development, but it is not possible to ascribe them to a single stage.

Douglas L Erwin (author of item 24):

While the article considers the relationship between micro- and macro-evolution, the statement above is inaccurate in saying that I am challenging the standard view of evolution. The treatment of macro-evolution in that paper is an extension, but by no means a challenge.

David W Deamer (author of item 35):

No! The misleading (and loaded) words, of course, are "greater realism". Those were supplied gratis by the Discovery Institute folks. The correct words would be "increased understanding". The main cultural gap separating thoughtful scientists from creationists and "intelligent design" adherents is that the life blood of science is to ask questions about the world around us, while the creationists seek a feeling of certainty that they have all the answers. Those answers, of course, are encapsulated in an unquestioning belief in religious doctrine (the creationists) or that the universe must have a greater purpose of some sort ("intelligent design"). Therefore whenever a scientist writes about questions to which we don't yet have answers, the creationists pounce on this "confession" as proof of weakness, implying that they have all the answers.

Again, more than half of the Discovery Institute's summaries were rejected as inaccurate and tendentious by the authors themselves. So if the DI were being graded on its ability to summarize these publications, it would score less than 50% - a failing grade in any school. Should the state of Ohio be guided in the development of its science standards by people who are apparently incapable of reliably and objectively summarizing the scientific literature?

4. What is the pedagogical value of the Bibliography?

The preceding sections have already amply demonstrated that the Discovery Institute's interpretation of the publications in the Bibliography is tendentious and that its understanding of the publications is unreliable. But what about the pedagogical value of the Bibliography?

According to the Bibliography, "These 44 scientific publications represent important lines of evidence and puzzles that any theory of evolution must confront, and that science teachers and students should be allowed to discuss when studying evolution."

But what is the basis of expertise and analysis on which the DI makes these judgments? Does the staff of the DI, to which the authorship of the Bibliography is credited, include any important scientific contributors to the topics discussed? No - significantly, the Bibliography contains no publications by anyone associated with the DI. Does the Bibliography cite the experience of any working K-12 science teachers? No. Does it rely on the research of any specialists in developing science curricula? No. Is any indication given in the Bibliography that the DI has actually examined the instructional materials in use in Ohio and ascertained their deficiencies? No. Are there any concrete suggestions in it for science teachers how to incorporate these publications in their lessons? No. There is merely the blanket, anonymous, unsubstantiated claim that these publications "represent important lines of evidence and puzzles that any theory of evolution must confront, and that science teachers and students should be allowed to discuss when studying evolution."

(The Discovery Institute may wish to claim in response that its Senior Fellow Jonathan Wells's book Icons of Evolution [2000] constitutes a contribution to the literature on science education. But the reviews of Icons of Evolution in the scientific journals have been uniformly scathing. For example, Jerry A Coyne's review in Nature - which, as the Bibliography proclaims, is "one of the top two science journals in the world" - concludes with the ironic comment that "Icons is exactly as even-handed and intellectually honest as one would expect from someone whose 'prayers convinced me that I should devote my life to destroying Darwinism'" [Coyne 2001; the passage Coyne quotes is from Wells's essay "Darwinism: Why I went for a second PhD", to be found on a Unification Church web site at http://www.tparents.org/Library/Unification/Talks/Wells/DARWIN.htm].)

NCSE's questionnaire also asked whether the authors considered their work appropriate for use in high-school biology classes. Some simply did not know; but several explained that their publications would be inappropriate for use in high-school biology classes, for a variety of reasons.

First, despite the Discovery Institute's boast that "Over half of the papers listed below were published within the past 2-3 years, with the remainder published throughout the 1990s", several respondents noted that their work was already outdated. For example, David M Williams (coauthor of item 18) wrote:

Our review was written nearly 10 years ago and things have moved on since then. Many of the possible solutions to data incongruence we suggested then have now been acted upon and molecules and morphology agree in many more cases. In fact, many more examples using molecules and morphology together highlight and clarify topics relating directly to many evolutionary issues.

Second, many respondents remarked that their publications were intended for a specialist audience; for example, Keith Stewart Thomson (author of item 30) replied, "No, it is totally inappropriate, as it can only be judged in terms of a knowledge of the particular detailed subject matter. It is part of a sophisticated professional discussion within a part of the subject of evolution, not a general exposition for general readers".

Third, several respondents explained that their work is as yet too speculative to be included in high-school biology classes. Leslie E Orgel (author of item 43), for example, remarked, "I work at the frontiers of present-day knowledge. I doubt that the time is ripe for a detailed and correct interpretation of my work at the high-school level." And Günther P Wagner (coauthor of item 31 and author of item 32) explains, "This is cutting-edge research, and we cannot yet know whether it will stand up under the scrutiny of our colleagues. There is too much work to be done to determine whether our ideas and results turn out to be correct and useful for further research." Orgel's and Wagner's attitude instructively contrasts with that of the promoters of "intelligent design", who wish for their views to be taught at the high-school level before they have been accepted by the scientific community.

NCSE also asked Brian J Alters, an internationally recognized expert on science education who holds appointments at Harvard University and McGill University, where he is the Director of the Evolution Education Research Centre, to comment on the pedagogical value of the Bibliography. Alters (who is also RNCSE's Associate Editor for Education) responded:

The Discovery Institute's "Bibliography of Supplementary Resources for Ohio Science Education"

[These items were included in the bibliography submitted to the Ohio State Board of Education by the Discovery Institute in support of its contention that there is scientific research in support of "intelligent design theory". NCSE asked the publications' authors to respond to the DI's contention. Respondents to NCSE's questionnaire are in boldface; authors who responded after NCSE's Analysis of the Bibliography was sent to the Ohio State Board of Education are indicated with an asterisk.]

1. Cao Y, Janke A, Waddell PJ, Westerman M, Takenaka O, Murata S, Okada N, Pääbo S, Hasegawa M. Conflict among individual mitochondrial proteins in resolving the phylogeny of eutherian orders. Journal of Molecular Evolution 1998; 47: 307-32.

2. Conway Morris S. Evolution: Bringing molecules into the fold. Cell 2000; 100: 1-11.

3. Doolittle WF. Tempo, mode, the progenote, and the universal root. In: Fitch W, Ayala F, ed. Tempo and Mode in Evolution. Washington (DC): National Academy Press, 1995. p 3-24.

4. Doolittle WF. At the core of the Archaea. Proceedings of the National Academy of Sciences USA 1996; 93: 8797-9.

5. Doolittle WF. Uprooting the tree of life. Scientific American 2000 Feb; 90-5.

6. Doolittle WF. Phylogenetic classification and the universal tree. Science 1999; 284: 2124-8.

7. Doolittle WF. The nature of the universal ancestor and the evolution of the proteome. Current Opinion in Structural Biology 2000; 10: 355-8.

8. Erwin DH. Early introduction of major morphological innovations. Acta Palaeontologica Polonica 1994; 38: 281-94.

9. Gura T. Bones, molecules...or both? Nature 2000; 406: 230-3.

10. Lee MSY. Molecular clock calibrations and metazoan divergence dates. Journal of Molecular Evolution 1999; 49: 385-91.

11. Lee MSY. Molecular phylogenies become functional. Trends in Ecology and Evolution 1999; 14: 177-8.

12. Leipe DD, Aravind L, Koonin EV. Did DNA replication evolve twice independently? Nucleic Acids Research 1999; 27: 3389-401.

13. Lockhart PJ, Cameron SA. Trees for bees. Trends in Ecology and Evolution 2001; 16: 84-8.

14. Mindell DP, Sorenson MD, Dimcheff DE. Multiple independent origins of mitochondrial gene order in birds. Proceedings of the National Academy of Sciences USA 1998; 95: 10693-7.

15. Morris P, CoBabe E. Cuvier meets Watson and Crick: The utility of molecules as classical homologies. Biological Journal of the Linnean Society 1991; 44: 307-24.

16. Mushegian AR, Garey JR, Martin J, Liu LX. Large-scale taxonomic profiling of eukaryotic model organisms: A comparison of orthologous proteins encoded by the human, fly, nematode, and yeast genomes. Genome Research 1998; 8: 590-8.

17. Naylor GJP, Brown WM.* Amphioxus mitochondrial DNA, chordate phylogeny, and the limits of inference based on comparisons of sequences. Systematic Biology 1998; 47: 61-76.

18. Patterson C, Williams DM, Humphries CJ. Congruence between molecular and morphological phylogenies. Annual Review of Ecology and Systematics 1993; 24: 153-88.

19. Richardson MK, Hanken J, Gooneratne MJ, Pieau C, Raynaud A, Selwood L, Wright, GM. There is no highly conserved stage in the vertebrates: implications for current theories of evolution and development. Anatomy and Embryology 1997; 196: 91-106.

20. van Holde KE. Respiratory proteins of invertebrates: Structure, function and evolution. Zoology: Analysis of Complex Systems 1998: 100: 287-97.

21. Weiss K. We hold these truths to be self-evident. Evolutionary Anthropology 2001; 10: 199-203.

22. Woese C.* The universal ancestor. Proceedings of the National Academy of Sciences USA 1998: 95: 6854-9.

23. Carroll RL. Towards a new evolutionary synthesis. Trends in Ecology and Evolution 2000; 15: 27-32.

24. Erwin D. Macroevolution is more than repeated rounds of microevolution. Evolution & Development 2000; 2: 78-84.

25. Gilbert SF, Loredo GA, Brukman A, Burke AC. Morphogenesis of the turtle shell: the development of a novel structure in tetrapod evolution. Evolution & Development 2001; 3: 47-58.

26. Rieppel O. Turtles as hopeful monsters. BioEssays 2001; 23: 987-91.

27. Gilbert SF, Opitz JM, Raff RA. Resynthesizing evolutionary and developmental biology. Developmental Biology 1996; 173: 357-72.

28. Miklos GLG. Emergence of organizational complexities during metazoan evolution: Perspectives from molecular biology, palaeontology and neo-Darwinism. Memoirs of the Association of Australasian Palaeontologists. 1993; 15: 7-41.

29. Shubin NH, Marshall CR. Fossils, genes, and the origin of novelty. Paleobiology 2000; 26 (4; supplement): 324-40.

30. Thomson KS. Macroevolution: The morphological problem. American Zoologist 1992; 32: 106-12.

31. Stadler BMR, Stadler PF, Wagner GP, Fontana W. The topology of the possible: Formal spaces underlying patterns of evolutionary change. Journal of Theoretical Biology 2001; 213: 241-74.

32. Wagner GP. What is the promise of developmental evolution? Part II: A causal explanation of evolutionary innovations may be impossible. Journal of Experimental Zoology 2001; 291: 305-9.

33. Ball P. Life's lessons in design. Nature 2001; 409: 413-6.

34. Brooks R. The relationship between matter and life. Nature 2001; 409: 409-11.

35. Deamer DW. The first living systems: A bioenergetic perspective. Microbiology and Molecular Biology Reviews 1997; 61: 239-61.

36. Katz MJ. Templets and the explanation of complex patterns. Cambridge (UK): Cambridge University Press, 1986.

37. Fraser CM, Gocayne JD, White O, Adams MD, Clayton RA, Fleischmann RD, Bult CJ, Kerlavage AR, Sutton GG, Kelley JM, Fritchman JL, Weidman JF, Small KV, Sandusky M, Fuhrmann JL, Nguyen DT, Utterback T, Saudek DM, Phillips CA, Merrick JM, Tomb J, Dougherty BA, Bott KF, Hu PC, Lucier TS, Peterson SN, Smith HO, Venter JC. The minimal gene complement of Mycoplasma genitalium. Science 1995; 270: 397-403.

38. Hutchison III CA, Peterson SN, Gill SR, Cline RT, White O, Fraser CM, Smith HO, Venter JC. Global transposon mutagenesis and a minimal mycoplasma genome. Science 1999; 286: 2165-9.

39. Koonin EV. How many genes can make a cell: The minimal-gene-set concept. Annual Review of Genomics and Human Genetics 2000: 1: 99-116.

40. Maniloff J. The minimal cell genome: "On being the right size". Proceedings of the National Academy of Sciences USA 1996; 93: 1004-6.

41. Mushegian AR, Koonin EV. A minimal gene set for cellular life derived by comparison of complete bacterial genomes. Proceedings of the National Academy of Sciences USA 1996; 93: 10268-73.

42. Peterson SN, Fraser CM. The complexity of simplicity. Genome Biology 2001; 2: 1-7.

43. Orgel LE. Self-organizing biochemical cycles. Proceedings of the National Academy of Sciences 2000; 97: 12503-7.

44. Szathmáry E. The evolution of replicators. Philosophical Transactions of the Royal Society of London B 2000;