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.
NSTA Position Statement — The Teaching of Evolution: National Congress on Science Education — 8/05CNG9, 8/05CNG10.