Statement on Evolution in Textbooks
by Authors of Biology Texts
March 26, 1999; updated September 8, 2003

Evolution and Science

The coverage of evolution in biology textbooks we have written reflects the broad consensus in the scientific community. As noted in a booklet issued by the National Academy of Sciences, "Evolution pervades all biological phenomena. To ignore that it occurred or to classify it as a form of dogma is to deprive the student of the most fundamental organizational concept in the biological sciences" (Science and Creationism, National Academy Press, 1985, p. 22).

Our textbooks are written from this point of view. Evolution occupies a prominent position, and is covered explicitly. Many sections use evolutionary concepts to explain the diversity of living and fossil organisms, the adaptations of organisms to their environments, and similarities of structure and function shared by related organisms. In this way, we present students with the understanding of biology shared by the overwhelming majority of working scientists in the United States and throughout the world.

What Do States Require of Biology Textbooks?

Although state requirements vary, the majority require that biology curricula must include extensive coverage of evolution. The few states where standards or curriculum guidelines do not mention evolution by name nonetheless require the coverage of evolutionary topics. If we omitted proper coverage of evolutionary facts and theories, we would not be in compliance with these and other curricula that require complete, accurate, up-to-date, and conceptually-based educational materials.

Our Message to Textbook Adopters

As scientists and teachers, we find it unacceptable that school districts considering our books for adoption would be encouraged to choose one book over another based on the perception that teachers should avoid the topic of evolution. We encourage school districts deciding among our books to use genuine scientific and educational criteria.

We also deplore the efforts made in some states and districts to require that evolution be disclaimed. Such disclaimers single out evolution from all other scientific ideas as somehow less reliable or less accepted by scientists, or as "only a theory." Evolution is a normal part of science, and should be treated the same way as all other scientific ideas. It does a disservice to students to mislead them about the important position that evolution holds in biological and other sciences.

Those who have joined in this statement do so as individuals. We do not speak on behalf of our publishers, but for ourselves, as biologists, authors, and educators.

LIST OF SIGNATORIES

PDF VERSION OF STATEMENT WITH SIGNATORIES

Note: This policy statement on the teaching of natural sciences, which was adopted by the State Board of Education in 1989, supersedes the State Board’s 1972 Antidogmatism Policy.

The domain of the natural sciences is the natural world. Science is limited by its tools—observable facts and testable hypotheses.

Discussions of any scientific fact, hypothesis, or theory related to the origins of the universe, the earth, and life (the how) are appropriate to the science curriculum. Discussions of divine creation, ultimate purposes, or ultimate causes (the why) are appropriate to the history–social science and English–language arts curricula.

Nothing in science or in any other field of knowledge shall be taught dogmatically. Dogma is a system of beliefs that is not subject to scientific test and refutation. Compelling belief is inconsistent with the goal of education; the goal is to encourage understanding.

To be fully informed citizens, students do not have to accept everything that is taught in the natural science curriculum, but they do have to understand the major strands of scientific thought, including its methods, facts, hypotheses, theories, and laws.

A scientific fact is an understanding based on confirmable observations and is subject to test and rejection. A scientific hypothesis is an attempt to frame a question as a testable proposition. A scientific theory is a logical construct based on facts and hypotheses that organizes and explains a range of natural phenomena. Scientific theories are constantly subject to testing, modification, and refutation as new evidence and new ideas emerge. Because scientific theories have predictive capabilities, they essentially guide further investigations.

From time to time natural science teachers are asked to teach content that does not meet the criteria of scientific fact, hypothesis, and theory as these terms are used in natural science and as defined in this policy. As a matter of principle, science teachers are professionally bound to limit their teaching to science and should resist pressure to do otherwise. Administrators should support teachers in this regard.

Philosophical and religious beliefs are based, at least in part, on faith and are not subject to scientific test and refutation. Such beliefs should be discussed in the social science and language arts curricula. The Board’s position has been stated in the History–Social Science Framework (adopted by the Board).1 If a student should raise a question in a natural science class that the teacher determines is outside the domain of science, the teacher should treat the question with respect. The teacher should explain why the question is outside the domain of natural science and encourage the student to discuss the question further with his or her family and clergy.

Neither the California nor the United States Constitution requires that time be given in the curriculum to religious views in order to accommodate those who object to certain material presented or activities conducted in science classes. It may be unconstitutional to grant time for that reason.

Nothing in the California Education Code allows students (or their parents or guardians) to excuse their class attendance on the basis of disagreements with the curriculum, except as specified for (1) any class in which human reproductive organs and their functions and process are described, illustrated, or discussed; and (2) an education project involving the harmful or destructive use of animals. (See California Education Code Section 51550 and Chapter 2.3 of Part 19 commencing with Section 32255.) However, the United States Constitution guarantees the free exercise of religion, and local governing boards and school districts are encouraged to develop statements, such as this one on policy, that recognize and respect that freedom in the teaching of science. Ultimately, students should be made aware of the difference between understanding, which is the goal of education, and subscribing to ideas.

Notes
1. History–Social Science Framework for California Public Schools (Updated edition with content standards). Sacramento: California Department of Education, 2001.

return to top

EMPIRE STATE ASSOCIATION OF TWO YEAR COLLEGE BIOLOGISTS (1998) *

Whereas: A popular movement to compromise the teaching of Evolution exists, and

Whereas: any compromise in the teaching of evolution weakens the teaching of biology in general, and

Whereas: efforts on the part of textbook publishers to accommodate special interest groups, such as the popular anti-evolution movement, contributes to the weakening of biology instruction, and

Whereas: this practice is most pronounced at the pre-college level, be it

Resolved: that the E.S.A.T.Y.C.B. opposes anything less than the full textbook presentation of evolution as it is currently accepted by the biological community, and be it further

Resolved: that the E.S.A.T.Y.C.B. opposes the introduction of non-biological ideas as alternatives to evolution, and be it further:

Resolved: that the E.S.A.T.Y.C.B. recommends that its members become aware of the publishers' policies concerning exclusion of sound scientific information to accommodate special interest groups and that these policies be considered when selecting a text.

return to top

IDAHO SCIENCE TEACHERS ASSOCIATION

The Teaching of Evolution

Evolution, in the broadest sense, can be defined as the idea that the universe has a history: that change through time has taken place. If we look today at the galaxies, stars, the planet Earth, and the life on planet Earth, we see that things today are different from what they were in the past: galaxies, stars, planets, and life forms have evolved. Biological evolution refers to the scientific theory that living things share ancestors from which they have diverged; it is called “descent with modification”. There is abundant and consistent evidence from astronomy, physics, biochemistry, geochronology, geology, biology, anthropology, and other sciences that evolution has taken place.

As such, evolution is a unifying concept for science. The National Science Education Standards recognizes that conceptual schemes such as evolution "unify science disciplines and provide students with powerful ideas to help them understand the natural world" (p. 104) and recommends evolution as one such scheme. In addition, Benchmarks for Science Literacy from AAAS’s Project 2061, as well as other national calls for science reform, all name evolution as a unifying concept because of its importance across the disciplines of science. Scientific disciplines with a historical component, such as astronomy, geology, biology, and anthropology, cannot be taught with integrity if evolution is not emphasized.

There is no longer a debate among scientists about whether evolution has taken place. There is considerable debate about how evolution has taken place: What are the processes and mechanisms producing change, and what has happened specifically during the history of the universe? Scientists often disagree about their explanations. In any science, disagreements are subject to rules of evaluation. Scientific conclusions are tested by experiment and observation, and evolution, as with any aspect of theoretical science, is continually open to and subject to experimental and observational testing.

The importance of evolution is summarized as follows in the National Academy of Sciences publication Teaching about Evolution and the Nature of Science: "Few other ideas in science have had such a far-reaching impact on our thinking about ourselves and how we relate to the world" (p. 21). The National Science Education Standards note that, "[e]xplanations of how the natural world changes based on myths, personal beliefs, religious values, mystical inspiration, superstition, or authority may be personally useful and socially relevant, but they are not scientific" (p. 201). Because science limits itself to natural explanations and not religious or ultimate ones, science teachers should neither advocate any religious interpretation of nature nor assert that religious interpretations of nature are not possible.

Some policy makers continue attempts to distort the teaching of evolution through mandates that would require teachers to teach evolution as "only a theory" or that require a textbook or lesson on evolution to be preceded by a disclaimer. Regardless of the legal status of these mandates, they are bad educational policy. Such policies have the effect of intimidating teachers, which may result in the de-emphasis or omission of evolution. As a consequence, the public will only be further confused about the nature of scientific theories. Furthermore, if students learn less about evolution, science literacy itself will suffer.

The Idaho Science Teachers Association (ISTA) strongly supports the position that evolution is a major unifying concept in science and should be included in the K-12 science education curricula. Furthermore, if evolution is not taught, students will not achieve the level of scientific literacy they need. This position is consistent with that of the National Academies, the American Association for the Advancement of Science (AAAS), and many other scientific and educational organizations.

ISTA also recognizes that evolution has not been emphasized in science curricula in many locations in a manner commensurate to its importance because of official policies, intimidation of science teachers, the general public's misunderstanding of evolutionary theory, and a century of controversy. In addition, some teachers are being pressured to introduce creationism, "creation science," intelligent design and other nonscientific views, which are intended to weaken or eliminate the teaching of evolution. Within this context, ISTA recommends that:

• all teacher certification institutions require courses in the nature of science and evolution.
• evolution be taught as an essential unifying concept in science that should be included in the K-12 curricula. Teachers of science should be supported in the teaching of evolution and the strong body of scientific evidence supporting it, and not be pressured to present nonscientific views.
• science curricula, Idaho state science standards, and teachers should emphasize evolution in a manner commensurate with its importance as a unifying concept in science and its overall explanatory power.
• science teachers should not advocate any religious interpretations of nature and should be nonjudgmental about the personal beliefs of students.
• policy makers and administrators should not mandate policies requiring the teaching of "creation science" or related concepts, such as so-called "intelligent design," "abrupt appearance," and "arguments against evolution." Administrators also should support teachers against pressure to promote nonscientific views or to diminish or eliminate the study of evolution.
• Administrators and school boards should provide support to teachers as they review, adopt, and implement curricula that emphasize evolution. This should include professional development to assist teachers in teaching evolution in a comprehensive and professional manner.
• Parental and community involvement in establishing the goals of science education and the curriculum development process should be encouraged and nurtured in our democratic society. However, the professional responsibility of science teachers and curriculum specialists to provide students with quality science education should not be compromised by censorship, pseudoscience, inconsistencies, faulty scholarship, or unconstitutional mandates.

• The diversity of life on earth is the outcome of evolution: an unpredictable and natural process of temporal descent with genetic modification that is affected by natural selection, chance, historical contingencies and changing environments.
  
  
• Biological evolution refers to changes in populations, not individuals. Changes must be successfully passed on to the next generation. This means evolution results in heritable changes in a population spread over many generations. In fact, evolution can be defined as any change in the frequency of alleles within a gene pool from one generation to the next.
  
  
• Evolutionary theory is significant in biology, among other reasons, for its unifying properties and predictive features, the clear empirical testability of its integral models and the richness of new scientific research it fosters.
  
  
• The fossil record, which includes abundant transitional forms in diverse taxonomic groups, establishes extensive and comprehensive evidence for organic evolution.
  
  
• Natural selection, the primary mechanism for evolutionary changes, can be demonstrated with numerous, convincing examples, both extant and extinct.
  
  
• Natural selection--a differential, greater survival and reproduction of some genetic variants within a population under an existing environmental state--has no specific direction or goal, including survival of a species.
  
  
• Adaptations do not always provide an obvious selective advantage. Furthermore, there is no indication that adaptations--molecular to organismal--must be perfect: adaptations providing a selective advantage must simply be good enough for survival and increased reproductive fitness.
  
  
• The model of punctuated equilibrium provides another account of the tempo of speciation in the fossil record of many lineages: it does not refute or overturn evolutionary theory, but instead adds to its scientific richness.
  
  
• Evolution does not violate the second law of thermodynamics: producing order from disorder is possible with the addition of energy, such as from the sun.
  
  
• Although comprehending deep time is difficult, the earth is about 4.5 billion years old. Homo sapiens has occupied only a minuscule moment of that immense duration of time.
  
  
• When compared with earlier periods, the Cambrian explosion evident in the fossil record reflects at least three phenomena: the evolution of animals with readily-fossilized hard body parts; Cambrian environment (sedimentary rock) more conducive to preserving fossils; and the evolution from pre-Cambrian forms of an increased diversity of body patterns in animals.
  
  
• Radiometric and other dating techniques, when used properly, are highly accurate means of establishing dates in the history of the planet and in the history of life.
  
  
• Recent findings from the advancing field of molecular genetics, combined with the large body of evidence from other disciplines, collectively provide indisputable demonstration of the theory of evolution.
  
  
• In science, a theory is not a guess or an approximation but an extensive explanation developed from well-documented, reproducible sets of experimentally-derived data from repeated observations of natural processes.
  
  
• The models and the subsequent outcomes of a scientific theory are not decided in advance, but can be, and often are, modified and improved as new empirical evidence is uncovered. Thus, science is a constantly self-correcting endeavor to understand nature and natural phenomena.
  
  
• Science is not teleological: the accepted processes do not start with a conclusion, then refuse to change it, or acknowledge as valid only those data that support an unyielding conclusion. Science does not base theories on an untestable collection of dogmatic proposals. Instead, the processes of science are characterized by asking questions, proposing hypotheses, and designing empirical models and conceptual frameworks for research about natural events.
  
  
• Providing a rational, coherent and scientific account of the taxonomic history and diversity of organisms requires inclusion of the mechanisms and principles of evolution.
  
  
• Similarly, effective teaching of cellular and, molecular biology requires inclusion of evolution.
  
  
• Specific textbook chapters on evolution should be included in biology curricula, and evolution should be a recurrent theme throughout biology textbooks and courses.
  
  
• Students can maintain their religious beliefs and learn the scientific foundations of evolution.
  
  
• Teachers should respect diverse beliefs, but contrasting science with religion, such as belief in creationism, is not a role of science. Science teachers can, and often do, hold devout religious beliefs, accept evolution as a valid scientific theory, and teach the theory's mechanisms and principles.
  
  
• Science and religion differ in significant ways that make it inappropriate to teach any of the different religious beliefs in the science classroom.
  
  

• The diversity of life on earth is the outcome of evolution: an unpredictable and natural process of temporal descent with genetic modification that is affected by natural selection, chance, historical contingencies and changing environments.
  
• Evolutionary theory is significant in biology, among other reasons, for its unifying properties and predictive features, the clear empirical testability of its integral models and the richness of new scientific research it fosters.
  
• The fossil record, which includes abundant transitional forms in diverse taxonomic groups, establishes extensive and comprehensive evidence for organic evolution.
  
• Natural selection, the primary mechanism for evolutionary changes, can be demonstrated with numerous, convincing examples, both extant and extinct.
  
• Natural selection -- a differential, greater survival and reproduction of some genetic variants within a population under an existing environmental state -- has no specific direction or goal, including survival of a species.
  
• Adaptations do not always provide an obvious selective advantage. Furthermore, there is no indication that adaptations -- molecular to organismal -- must be perfect; adaptations providing a selective advantage must simply be good enough for survival and increased reproductive fitness.
  
• The model of punctuated equilibrium provides another account of the tempo of speciation in the fossil record of many lineages: it does not refute or overturn evolutionary theory, but instead adds to its scientific richness.
  
• Evolution does not violate the second law of thermodynamics; producing order from disorder is possible with the addition of energy, such as from the sun.
  
• Although comprehending deep time is difficult, the earth is about 4.5 billion years old. Homo sapiens has occupied only a minuscule moment of that immense duration of time.
  
• When compared with earlier periods, the Cambrian explosion evident in the fossil record reflects at least three phenomena: the evolution of animals with readily fossilized, hard-body parts; a Cambrian environment (sedimentary rock) more conducive to preserving fossils; and the evolution from pre-Cambrian forms of an increased diversity of body patterns in animals.
  
• Radiometric and other dating techniques, when used properly, are highly accurate means of establishing dates in the history of the planet and in the history of life.
  
• In science, a theory is not a guess or an approximation but an extensive explanation developed from well-documented, reproducible sets of experimentally-derived data and from repeated observations of natural processes.
  
• The models and the subsequent outcomes of a scientific theory are not decided in advance, but can be, and often are, modified and improved as new empirical evidence is uncovered. Thus science is a constantly self-correcting endeavor to understand nature and natural phenomena.
  
• Science is not teleological: the accepted processes do not start with a conclusion then refuse to change it, or acknowledge as valid only those data that support an unyielding conclusion. Science does not base theories on an untestable collection of dogmatic proposals. Instead, the processes of science are characterized by asking questions, proposing hypotheses and designing empirical models and conceptual frameworks for research about natural events.
  
• Providing a rational, coherent and scientific account of the taxonomic history and diversity of organisms requires inclusion of the mechanisms and principles of evolution.
  
• Similarly, effective teaching of cellular and molecular biology requires inclusion of evolution.
  
• Specific textbook chapters on evolution should be included in biology curricula, and evolution should be a recurrent theme throughout biology textbooks and courses.
  
• Students can maintain their religious beliefs and learn the scientific foundations of evolution.
  
• Teachers should respect diverse beliefs, but contrasting science with religion, such as belief in creationism, is not a role of science. Science teachers can, and often do, hold devout religious beliefs, accept evolution as a valid scientific theory and teach the theory's mechanisms and principles.
  
• Science and religion differ in significant ways that make it inappropriate to teach any of the different religious beliefs in the science classroom.
  
  

• Develop outreach efforts that build off the momentum that will be generated by the fall, 2001 release of the WGBH television series Evolution.
  
• Emphasize evolution at annual and regional meetings by holding symposia focusing on evolution, teacher workshops, short courses, incentives for student research in evolution, etc.
  
• Provide information and crash-courses for journalists who write about evolution.
  
• Link web pages related to evolution education across scientific disciplines and among scientific and educational organizations.
  
• Partner among scientists and educators to develop teaching modules and resources that have an evolutionary theme.
  
• Provide useful informational resources to members who want to help with local efforts to support the teaching of evolution.
  
• Reach out to scientific, educational, political, governmental, religious, philanthropic, and private sector partners to accomplish the goals of support the teaching of evolution.