Explore Evolution The Arguments for and Against Neo-Darwinism

Paul Nelson

Reply to NCSE on Universal Genetic Code

The NCSE asserts that Explore Evolution‘s discussion of the universal genetic code, its variants, and puzzles ab The NCSE asserts that Explore Evolution‘s discussion of the universal genetic code, its variants, and puzzles about the origin of the variant codes, “is based on misunderstanding and/or misrepresentation of the available knowledge and of the scientific record.” The NCSE’s own discussion of this area, however, is very deeply confused. The NCSE does not grasp basic facts about the variant code puzzle, and this leads to several serious errors in their discussion. 1. Making a hash of a fascinating puzzle — the NCSE discussion We begin with the NCSE’s most serious error. They write: First, contrary to the key assertion [of EE], scientists have been aware of Read More ›

The Creationism Gambit

Science requires dissent and open inquiry for its very existence. This is true for high school students and teachers no less than for research scientists. For extra-scientific reasons, however, some members of the science establishment have long sought to protect the teaching of evolutionary theory from evidential challenges and dissent. Probably the most effective strategy for quenching such dissent is to label it as “creationism.” Since the teaching of creationism in public school science classrooms has been ruled unconstitutional, one can effectively foreclose awkward but perfectly reasonable questions about evolution simply by saying, “Well, that’s the sort of question a creationist would ask — and creationism is out of bounds in this classroom.” Let’s call this the creationism gambit. The creationism Read More ›

Evolution and Testability

One question counts above all else in natural science: How can this idea—theory, hypothesis, claim—be tested? Testability gains its primacy in science from our deep understanding that empirical knowledge does not rest on authority, tradition, or majority rule, but rather on the testimony of nature itself. We can picture the structure of scientific knowledge and inquiry as a three-way relation, a logical and evidential triangle, where the three vertices are (1) the scientific community, (2) scientific theories, and (3) the physical world, or nature itself. Each of these is a necessary element of the scientific enterprise. Take away scientists, and no science will be done. Take away theories, and science loses its structure. Take away nature itself, however, and science Read More ›

Introduction: The Catechism Versus the Data

On September 24, 2008, biologist and science writer John Timmer published an online review of the supplementary biology textbook Explore Evolution (EE). Timmer had previously written about EE without having read it, so Discovery Institute sent him a copy. Alas—having EE in his hands improved neither the quality of Timmer’s writing about the book, nor indeed his coverage of the relevant science. In fact, Timmer so baldly misrepresents both the content of Explore Evolution, but especially the associated scientific evidence and controversies, that his review perfectly illustrates the need for a book like EE. Our reply will reverse the order of Timmer’s review. He starts by using nearly 1200 words to speculate about the motives of EE‘s authors. Since Timmer Read More ›

Molecular Phylogeny and Phylogenetic Trees

The National Center for Science Education critique of Explore Evolution argues that molecular data confirm the theory of common ancestry. This might be the case, if it were possible to show how molecular data could also disconfirm the theory of common ancestry. But here, as elsewhere in their rebuttal, the NCSE presupposes common ancestry as a first principle. Molecular data should fit to a monophyletic tree. In this respect, of course, the NCSE rebuttal reflects widespread reasoning, and actual practice, within evolutionary biology and systematics. Start with the geometry (or topology) of a tree, and locate the data on that geometry. As Sober and Steel (2002, 395) note, This proposition [of common ancestry] is central because it is presupposed so widely in Read More ›

Malcolm Gordon and the Origin of Tetrapods

John Timmer accuses Explore Evolution of what he calls the “find a Ph.D.” approach: “if you look hard enough, you can find someone with a PhD who will say anything.” In this instance, Timmer disparages the minority viewpoint of UCLA biologist Malcolm Gordon (a tenured professor, actually), who has argued that the tetrapods may have evolved polyphyletically (i.e., more than once). It’s the textbook catechism again: why bother with citing some lone dissenter like Gordon? Timmer counts noses, and the sum determines what is worthy of attention. Claim that the scientists cited in EE pale in numbers to those who support the catechismal view, and voilá, case closed. There is no controversy and we can all go home. This is science by census. But Read More ›

The “Fact” of Evolution

What is the “fact” of evolution? John Timmer in his critique of Explore Evolution (EE), argues that “aspects of the theory [of evolution] can be safely treated as fact,” and in support of this point, cites a paper by the Canadian geneticist T. Ryan Gregory, entitled “Evolution as Fact, Theory and Path.” Here is how Gregory (2008, 49) defines the “fact” of evolution: The notion that species may change through time and that living organisms are related to one another through common descent…species have changed over time and are connected by descent from common ancestors. Change through time, descent of organisms from common ancestors—hey, that sounds familiar: Evolution #1: “Change over time” First, evolution can mean that the life forms we see Read More ›

The Definitions of “Evolution”

The National Center for Science Education (NCSE) alleges that Explore Evolution (EE) uses “erroneous” and “irrelevant” definitions of the term “evolution” and employs “a false distinction between microevolution and macroevolution.” These errors are said to flow from a “modern creationist strategy” of misrepresenting the definitions of science and evolution. Evolution, according to the NCSE, is a “single concept.” Really? Beginning with Darwin himself, evolutionary biologists have distinguished the theory that evolution (i.e., descent with modification) occurred from hypotheses about how evolution occurred. Indeed, it would be impossible to understand post-Darwinian controversies about, for instance, the relative importance of natural selection, if “evolution” were a single, or unitary concept, or if logically and evidentially distinct notions referred to as “evolution”—such as change over Read More ›

Monophyly vs. Polyphyly and Christian Schwabe

One theme of Explore Evolution (EE) addresses differing views among evolutionary biologists about Darwin’s Tree of Life, i.e., the theory of the universal common ancestry of all organisms on Earth: more precisely, the monophyly of terrestrial life, rooted in the Last Universal Common Ancestor, or LUCA. While the majority position within evolutionary biology endorses monophyly, a growing minority of workers argue for multiple independent origins, or polyphyly (see below). It’s an important controversy, well worth the attention of textbooks. But John Timmer accuses EE of a “bait-and-switch” move in describing this controversy. By “lumping…together in a single footnote” several scientists with very different views about the overall pattern of life’s history, he argues, EE tries for “borrowed credibility,” misleading its readers about the true outlines of Read More ›

The Arguments for and Against Neo-Darwinism