Backgrounder and summary of publisher’s proposed revision to biology textbooks

Discovery Institute
October 30, 2003
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Publishers Start Correcting Errors, but Lots of Problems Remain

This document summarizes:
1. Top 10 Corrections Made by Publishers
2. Areas Where Textbooks Contradict Each Other
3. Top Remaining Factual Errors

1. Top 10 Corrections Made by Publishers
  • Haeckel’s Embryos Removed! Two of the three textbooks that included bogus embryo diagrams (“Haeckel’s embryos”) that overstate the similarities between animal embryos have now dropped these drawings and replaced them with photos. [Biology (Raver, LeBel); and Biology (Raven and Johnson, McGraw Hill)] The publisher of the third textbook [Biology (Starr and Taggart, Thomson)] has not yet released its changes.
  • Gill Slits Removed! One textbook has removed remaining inaccurate references to gill slits in chordate embryos. [Glencoe Biology, pp. 770, 779, 787]
  • Darwin’s theory is NOT the “essence of biology.” One textbook has corrected its overstatement that “Darwin’s theory of natural selection is the essence of biology....” and replaced it with the more objective statement that “Darwin’s theory of evolution by natural selection provides a consistent explanation for life’s diversity.” [Holt Biology, p. 9]
  • Miller-Urey Qualified. Two textbooks have now inserted acknowledgments that the Miller-Urey origin of life experiment was based on ideas about the earth’s early atmosphere no longer accepted by scientists. [Glencoe Biology; Holt Biology]
  • Fossil Record Gaps. One textbook [Glencoe Biology] has added a stronger statement about the incompleteness of the fossil record (p. 400).
  • Evolutionary Intermediates. One textbook has qualified an earlier claim made about evolutionary intermediates. The original textbook claimed that “since Darwin's time, many of these intermediates have been found.” The revised text now reads: “Since Darwin’s time, some of these intermediates have been found, while others have not.” [Holt Biology, p. 283]
  • Darwin and Genetics. One textbook has corrected a statement that falsely implied that Charles Darwin knew about genetics. [Holt Biology, p. 9]
  • Genetic Mutations are Usually Harmful. One text has added a sentence on to make clearer the fact that genetic mutations (the source of new innovations according to neo-Darwinism) are usually harmful. The original wording downplayed this fact by stating merely that errors produced by genetic mutations “can disrupt a protein’s function.” The new wording makes clear that the errors produced “will usually disrupt a protein’s function.” [Holt Biology, p. 283]
  • RNA World Problems. One text has added a more detailed statement about the problems of the RNA world hypothesis. (“Although experiments have shown that RNA is capable of some of the functions that would be necessary in an RNA world, many functions have not yet been demonstrated, and the transition to a DNA world is currently unknown.” p. 388).
  • Peppered Moth Concession. One publisher has inserted a minor a clarification about peppered moths into the Teacher’s Edition of one of its texts, noting that “other studies have failed to completely duplicate Kettlewell’s results.” (Glencoe Biology, Teacher’s Edition).

2. Areas Where Textbooks Contradict Each Other
  • Peppered moths. Only one textbook clearly identifies some of the problems with classical peppered moth experiments [Biology (Raven and Johnson, McGraw Hill)] and in defense of this text McGraw Hill states that it is a “fact” (yes, a FACT) “that the ‘bird predation’ explanation of industrial melanism is no longer supported by strong experimental data” and it boasts that this “fact… is clearly stated” in the Raven and Johnson text. However, two other McGraw Hill textbooks [Mader’s AP biology text and Glencoe Biology] continue to present the bird predation hypothesis completely uncritically! Other textbooks do the same!
  • Gill Slits. Some textbooks have removed the inaccurate use of the term “gill slits,” but one has not. Interestingly, McGraw Hill has removed this bogus claim from its general biology textbook, but defends the exact same claim in its AP textbook authored by Raven and Johnson!
  • Cambrian Explosion. One textbook claims that the Cambrian Explosion took 10-20 million years [Biology (Raver, LeBel)], while another says it took 30-160 million years [Holt Biology]. The standard scientific dating of the Cambrian Explosion is actually 5-10 million years.

3. Top Remaining Factual Errors
  • Miller-Urey Experiment. Most accounts of the Miller-Urey origin of life experiment mislead students into thinking that revised Miller-Urey experiments have produced results helpful to understanding the origin of the first life. In fact, those experiments are now widely considered a dead-end by origin of life researchers. According to an article published in 2003 by the International Society for the Study of the Origin of Life: “It is now clear that Miller-like experiments create too many biological molecules, in mixtures that are too complex to self-organize in a way rationally likely to lead to replication. The intrinsic reactivity of organic material under the influence of energy is to create tar, not life; the enviable ability of minerals to fractionate themselves into organized forms is not displayed by organic materials in standard solvents at surface temperatures and pressures on Earth. Every additional molecule can be as easily an inhibitor for the formation of life rather than a contributor.” ( )
  • Peppered Moth Story. Several textbooks still present the classical peppered moth story as if it is good science, when it’s not.
  • Human Gill Slits. At least one textbook continues to make the bogus claim that human embryos have “gill slits.”
  • Cambrian Explosion. One textbook wrongly states that the Cambrian Explosion took 160 million years, when the standard accepted dating is 5-10 million years.
  • Homology. Some textbooks claim that all homologous structures, including vertebrate limbs, follow the same path of embryological development, which is false.
  • Embryology. Some textbooks continue to imply that animal embryos are the most similar in their earliest stages, and differences only become apparent later in the developmental process, which is untrue.
  • Flat Earth Myth. One textbook [LeBel] claims that Europeans still believed in the “flat earth” until the 1500s (after Columbus). This myth has been refuted by historians, most notably by University of California historian Jeffrey Burton Russell in his book Inventing the Flat Earth (New York: Praeger, 1997).
  • Inaccurate Attacks on Intelligent Design. Two textbooks have inserted one-sided and factually inaccurate attacks on intelligent design.

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