This final chapter of Explore Evolution makes grandiose, and ultimately untrue, claims about how the process of science works and how the scientific community deals with dissenting views. The errors in this chapter begin with the title. While claiming to discuss dissent within science, it actually centers on a debate between science and nonscience. In muddying the straightforward distinction between the science of evolution and the pseudoscience of creationism, Explore Evolution misleads students not only about evolution, but about how scientific inquiry proceeds. In service of this last effort to confuse students, the authors repeat their misrepresentations of Malcolm Gordon's views, and obfuscate the true nature of an ongoing discussion about the shape of the universal tree of life. In attempting to defend themselves against charges of misrepresenting and misquoting scientists (a section not necessary in most science textbooks), the authors draw an inaccurate analogy between science and courtroom testimony, and them misstate how courtrooms actually work, not to mention accepted standards of scientific discourse.
p. 142: "an evolutionary biologist … disagree[s] with Universal Common Descent."
The example offered in fact argues that there is a single tree of life, which may have multiple roots. As discussed in other chapter critiques, Explore Evolution misrepresents ongoing research into the shape of the early tree of life in order to advance a scientifically baseless creationist claim.
p. 142: "Michael Behe, a … biochemist who is a … critic of the power of the mutation/selection argument"
Behe has resurrected long-discredited creationist arguments and uses his academic credentials to give them a gloss of scientific respectability. Behe is one of the few anti-evolution activists to accept common descent of all life, including humans, but states that a definition of science which would admit his anti-evolution views would also treat astrology as science.
p. 142: "'the creationists' vs. 'the evolutionists,' a familiar and predictable storyline"
Treating creationism as a form of "dissent in science" is inaccurate. Creationism rejects basic scientific principles in pursuit of a religious agenda. Since it is not a scientific enterprise, it does not belong in science class. Just because something is "familiar and predictable" doesn't mean it is wrong, and trivializing this important distinction misinforms students on a basic level.
p. 143: "dissenters are accused of 'misquotation' or 'misrepresentation.' But is this really true?"
Even within this chapter, scientist Malcolm Gordon's words are taken out of context and twisted to misrepresent his views on evolution. This book is filled with such errors, and the defense offered is scant and irrelevant to the charges. Even in court, a witnesses words may not be used without an opportunity for cross-examination and clarification, precisely because the context of a statement does indeed matter.
p. 143: "Practicing science should be about … using all the evidence … whatever its source"
Scientific evidence must possess certain qualities. Other scientists must be able to make the same measurements, and compare their own experiences of the data with other authors. Some valid forms of knowledge do not fit these criteria, including religious beliefs, hunches, intuition, and aesthetic feelings.
p. 143: "By now, we hope you can see that real science as it's actually practiced can be a very lively subject."
Science as it is practiced is indeed a very lively subject, filled with active debates. Explore Evolution manages to avoid or misrepresent the debates actually going on within evolutionary biology while dredging up long-discredited pseudo-scientific attacks.
Nature of Science: Dismissing the distinction between scientific understanding of evolution and the religious commitment to creationism as "a familiar and predictable storyline" ignores the important scientific and practical reasons why that distinction matters. Students deserve better than to have the basic definition of science muddled in order to advance the religious agenda of the authors of Explore Evolution. Just because the distinction is familiar and predictable doesn't make it wrong. It does not serve students to muddy the waters regarding how scientists evaluate evidence. Explore Evolution cracks the door to unscientific evidence being raised in science class, misleading students and harming their broader science education as well as their understanding of evolution.
Standards of scientific discourse: Explore Evolution attempts to create an analogy between scientific debate and a courtroom cross-examination. This misrepresents the way scientific debates are settled, as well as misstating the way courtrooms operate. For instance, courts limit the sorts of evidence a jury considers, and requires that witnesses be cross-examined so that biases and misinterpretations can be resolved. Hearsay is inadmissible, but Explore Evolution relies more on quotations from scientists than on the actual data they've obtained. That those quotations are often stripped of important context and misquoted or misrepresented is only one of many errors in the treatment of scientific discourse. In dismissing these accusations, the book again does students a disservice.
Polyphyly and Malcolm Gordon: Explore Evolution claims the scientific community has two fundamentally different views of common descent, the single tree of life (monophyletic) and the orchard of life (polyphyletic). This claim distorts the meaning of a polyphyletic group. Explore Evolution then implies that because there are evolutionists, such as Malcolm Gordon, who question the monophyletic origins of life and of tetrapods, they must also "disagree with universal common descent," and must therefore support the creationist orchard view of life. This is false.
Explore Evolution claims the scientific community has two fundamentally different views of common descent, the single tree of life (monophyletic) and the orchard of life (polyphyletic). This claim distorts the meaning of a polyphyletic group. Explore Evolution then implies that because there are evolutionists, such as Malcolm Gordon, who question the monophyletic origins of life and of tetrapods, they must also "disagree with universal common descent" and therefore support the orchard view of life.
From Explore Evolution:
Scientists who think that history of life is best represented by a single branching tree have what is called a monophyletic view ("mono" means one or single). Scientists who have a polyphyletic view ("poly" means many) think the history of life looks more like an orchard of separate trees.
As part of this tree discussion, we have to make an important distinction between the terms common descent and Universal Common Descent. You may think that these terms mean the same thing. They don’t. As we've just seen, it's possible to think that some organisms share a common ancestor without thinking that all organisms are descended from a single common ancestor.EE, p10
The Neocreationist orchard: "Figure:4 A polyphyletic (orchard) view: branching within major groups, but no connections between them." EE, p. 10.
Explore Evolution is silent upon whether this orchard of life is composed of 3 trees or a 3 million trees, nor does Explore Evolution offer students any means by which they could make that distinction.
As discussed earlier in the critique of the Explore Evolution's Introduction, this view of polyphyletic trees is fully embraced by creationists. Indeed, there is a small group of Creation-scientists, baraminologists, who hope to find out how many trees, "created kinds" are in their orchard of life.
Taxonomy for baraminologists (biologists/paleontologists/zoologists who study the original created kinds) is one of detecting continuity and discontinuity. While the secular tree of life is essentially monophyletic (having one root), creationists view the tree of life as being polyphyletic (having multiple roots — each root being a created kind, or "baramin"). Thus, we have continuity between created kinds and offspring, and discontinuity between separate created kinds.
This creationist view of polyphyletic group contrasts with its usage in evolutionary biology. According the textbook Evolution (2007) by Barton and colleagues.
It is frequently useful to refer to groups by how they relate to each other on a phylogenetic tree (Figs. 5.3 and 5.4). The simplest grouping is that of a monophyletic group, or clade, which consists of an ancestor and all of its descendants…. In other situations, species are treated as a group because of some shared biological features, even though they do not share a common ancestor to the exclusion of other species. Such a collection of species is a polyphyletic group (derived from many (poly) ancestors; Fig. 5.3) Examples include gliding mammals (made up of species related to both fox and squirrels), gram-negative bacteria (see Fig. 6.2) and algae (see p. 198).Barton et al., (2007) Evolution, p. 111
Phylogenetic Trees: In each panel, the phylogenetic group is depicted by a green shaded circle. A) Monophyletic group. A species (C and D) share a common ancestor (E) not shared by any other species. (B) Paraphyletic group. All species in the group share a common ancestor (F), but some species (D) have been excluded from the group. (C) Polyphyletic group. A grouping of lineages each more closely related to other species not in the group than they are two each other.
From Barton et al., (2007) Evolution, p. 111.
To suggest that at least some mainstream evolutionary biologists accept the orchard view, Explore Evolution "quotes" Malcom Gordon, a paleontologist at UCLA who studies fish evolution.
Statement A
"The phenomenom of a monophyletic [single] origin of the universal tree of life probably did not occur. … At the macro-scale life appears to have had many origins."… Statement A was made by Malcolm Gordon, an evolutionary biologist at UCLA … Would you have guessed that an evolutionary biologist would disagree with Universal Common Descent?EE, p. 142
Would you have guessed that Malcolm Gordon is being misrepresented by Explore Evolution?
The universal tree of life probably had many roots.M. Gordon et al., (1999) "The Concept of Monophyly: A Speculative Essay," Biology and Philosophy, p. 331
An example of such a tree is shown below.
Modern tree of life: From W. Ford Doolittle (2000) "Uprooting the tree of life." Scientific American, 282(2):90-5. Note that distances are not necessarily to scale in this image. This image reflects a view held by some practicing scientists (including Dr. Doolittle, the author of the original article) that there was a period in life's early history when genes swapped so frequently that it is impossible to treat those earlier lineages as truly distinct, nor to trace those lineages back cleanly to a single ancestor. They do not dispute that life has some common ancestor, but they do seek to clarify how we talk about that ancestor.
This view of the tree of life with a reticulated network of roots replaces the concept of the last universal common ancestor (LUCA) with the concept of a community of common ancestors who are related to one another via genetic exchanges. Although the reticulated tree of life began as a controversial idea, it is now fully embraced as a plausible evolutionary scenario.
As Barton and colleagues explain in their textbook Evolution (2007):
DNA can be passed from one evolutionary lineage to another, by a process known as lateral gene transfer. … For our purposes, what is important is that lateral gene transfer creates chimeric organisms- organisms in which different parts of the genomes have different histories. … It therefore follows that there cannot be single "Tree of Life". That is, a single tree cannot accurately represent the evolution of life. It may be better to represent species evolution as a reticulated network (eg. Fig 5.23B) with interconnecting branches.Barton et al., (2007) Evolution, p. 131-132
Scientists can be skeptical about a single universal common ancestor and accept universal common ancestry.
So we end up with the "the creationists" versus the "evolutionists," a familiar and predictable storyline that, sadly, rolls over most of the fascinating (and relevant!) details about what individual scientists may actually think. Would you have guessed that an evolutionary biologist would disagree with Universal Common Descent?Explore Evolution, p. 142
It is not simply creationists versus evolutionists that is at issue. More accurately, it is creationists, including young earth-creationists, old earth creationists and intelligent design creationists versus modern science. All of these forms of creationism deny a fundamental ground rule of modern science – that science searches for natural explanations for natural phenomena.
The blatant mischaracterization of Malcolm Gordon's views on common ancestry neatly highlights an often used strategy of creationists: In the absence of scientific support, argue by misrepresenting fragments of text.
Another problem arises, when dissenting scientists quote the work of their colleagues, many of whom question certain aspects of neo-Darwinism, or parts of the case for it, while still happily calling themselves "evolutionary biologists" or :neo-Darwinists" … Often, in such cases, dissenters are accused of "misquotation" or "misrepresentation." But is this really true?Explore Evolution, p. 142-143
Apparently so. Explore Evolution misrepresents Malcolm Gordon's view of the tree of life by claiming that he "would disagree with Universal Common Descent." As discussed earlier, Malcolm Gordon's argument is not with universal common descent, but whether all life descended from a single common ancestor. Explore Evolution achieved the misrepresentation by misquotation, omitting a key sentence, shown in bold below, that explained Gordon’s view.
At the macro-scale life appears to have had many origins. The base of the universal tree of life appears not to have been a single root, but was instead a network of inextricably intertwined multiple branches deriving from many, perhaps 100 or more, genetic sources (Pennisi 1998b).M. Gordon et al., (1999) "The Concept of Monophyly: A Speculative Essay," Biology and Philosophy, p. 335
Any claim that scientists have not been presenting the full empirical evidence about evolution is blatantly false. Whenever there has been any plausible evidence that suggests problems with the received view of evolution, scientists have been excited to investigate them (Sarkar 2007, Chapter 10). In the 1960s scientists were excited about the proposal that most evolutionary changes at the molecular level were "neutral" and not selected for. In the 1980s scientists debated the possibility that evolution consists of small bursts of change followed by long periods of stasis (what Stephen Jay Gould and Niles Eldredge called "punctuated equilibrium"). In the 1990s biologists debated whether bacterial mutations were "directional," that is, more likely to occur in conditions favorable to them than in those that were not.
The overall view of evolution has so far barely been modified to respond to all these challenges and eighty years of new data. Our confidence in the correctness of the models that comprise the theory of evolution is exactly because of the "specifics" of the evidence.
Additionally, there is a strong disanalogy between scientific reasoning and legal reasoning in the Anglo-American context. Though there are plenty of scientific disputes, the scientific method is not in principle adversarial with each side arguing its case to the detriment of the other. Rather, scientific research is investigative and all honest workers have to consider all the evidence. This is exactly what creationists do not practice even when they claim to be concerned with the "specifics."
The current intelligent design debate has been going on for well over a decade, and I think the panelists and probably many of you will agree, it’s locked in a kind of holding pattern. This is not the first time tonight that you heard about molecular machines. Most of you, I think, a healthy percentage of this audience finds that evidence compelling … Yet the scientific community itself is unpersuaded. They’re unpersuaded. And they have two major criticisms of intelligent design and these are intimately related to one another. The first one is that there is no independent evidence for the cause, namely the designer. We don’t have any direct observational access to whatever being built that bacterial motor, if that bacterial motor was in fact designed and built by an intelligence. So, that’s the first one, there’s no independent evidence of the designer and there are no novel results and findings stemming from intelligent design independent of its criticisms of evolution.P. Nelson (2004) Molecular Machines and the Death of Darwinism
Given, as the authors of Explore Evolution say, that scientists often disagree about how to interpret evidence, the absence of any credible scientific disagreement on the evidence for evolution shows how well-confirmed that theory is. Scientists do disagree about how to interpret evidence--and evolutionary theory has withstood this scrutiny.
McCausland, I. 1999. “Anomalies in the History of Relativity.” Journal of Scientific Exploration 13: 271 -290.
Sarkar, S. 2007. Doubting Darwin? Creationist Designs on Evolution . Malden, MA: Blackwell Publishing.
In discussing dissent in science, Explore Evolution continues to misrepresent the nature of science itself. Science is treated as a courtroom trial with scientists serving as "expert witnesses" and students acting as juries, selecting their preferred outcome from several debating advocates. The "Case for"/"Case against" structure of the book is held out as an example of how science works and should work, with disagreeing voices presented without a context of experimentation and hypothesis testing.
Science certainly can be adversarial, but there are rarely only two sides to scientitific disagreements, and no participant in the scientific process should act like a jury – silent and disconnected. Scientific inquiry requires active participation: forming hypotheses, gathering data to test those hypotheses, modifying the hypothesis to reflect new evidence, and discussing (not debating) the meaning of results. Debate implies two fixed sides, with one absolutely right and the other absolutely wrong. Scientific discourse relies on the willingness of all involved to adjust their views as new evidence becomes available. Explore Evolution, by misrepresenting the scientific process, the views of practicing scientists, and the knowledge gained by scientific practice, shows no such willingness.
Science is about the pursuit of reliable knowledge that offers cogent explanations and testable predictions. Explore Evolution cannot show how real science works, because to do so would expose itself as a slick exercise in manufactured controversy.
From Explore Evolution:
Practicing science should be about making a vigorous effort to make true statements about the natural world, using all the evidence we have gathered, whatever its source, wherever it leads.Explore Evolution, p. 143
Scientists rely on evidence which is disprovable and testable. Sometimes that requires setting aside evidence like intuitions, gut feelings, or religious texts.
How does Paul Nelson, an author of Explore Evolution, foresee "using all the evidence" to make "true statements about the natural world"? Through the inclusion of religious scripture, and through intuition and gut feelings:
Within the past decade, the ID community has matured around the insights of UC Berkeley professor Phillip Johnson, whose central insight is that science must be free to seek the truth, wherever it lies. … The possibility of design, therefore, cannot be excluded from science. Under the canopy of design as an empirical possibility, however, any number of particular theories may also be possible, including traditional creationism. Both scientific and scriptural evidence will have to decide the competition between these theories.P. Nelson (2002) "Life in the Big Tent: Traditional Creationism and the Intelligent Design Community," Christian Research Journal 24,4
Elsewhere, he acknowledged that intelligent design creationism relies on non-scientific standards of evidence:
We don't have … a theory right now, and that's a problem. Without a theory, it's very hard to know where to direct your research focus. Right now, we've got a bag of powerful intuitions, and a handful of notions … but, as yet, no general theory of biological design.Paul Nelson, quoted in "The Measure of Design," interview with Jed Macosko, Phillip Johnson, William Dembski, Paul A. Nelson, et al., Touchstone July/August, 2004, p. 64-65
This is the spirit animating Explore Evolution, a desire to elevate intuition and faith above science within the science classroom.