Scientific Evidence Supporting Evolution Continues To Grow; Nonscientific Approaches Do Not Belong In Science Classrooms
WASHINGTON -- The National Academy of Sciences (NAS) and Institute of Medicine (IOM) today released SCIENCE, EVOLUTION, AND CREATIONISM, a book designed to give the public a comprehensive and up-to-date picture of the current scientific understanding of evolution and its importance in the science classroom. Recent advances in science and medicine, along with an abundance of observations and experiments over the past 150 years, have reinforced evolution's role as the central organizing principle of modern biology, said the committee that wrote the book.
"SCIENCE, EVOLUTION, AND CREATIONISM provides the public with coherent explanations and concrete examples of the science of evolution," said NAS President Ralph Cicerone. "The study of evolution remains one of the most active, robust, and useful fields in science."
"Understanding evolution is essential to identifying and treating disease," said Harvey Fineberg, president of IOM. "For example, the SARS virus evolved from an ancestor virus that was discovered by DNA sequencing. Learning about SARS' genetic similarities and mutations has helped scientists understand how the virus evolved. This kind of knowledge can help us anticipate and contain infections that emerge in the future."
DNA sequencing and molecular biology have provided a wealth of information about evolutionary relationships among species. As existing infectious agents evolve into new and more dangerous forms, scientists track the changes so they can detect, treat, and vaccinate to prevent the spread of disease.
Biological evolution refers to changes in the traits of populations of organisms, usually over multiple generations. One recent example highlighted in the book is the 2004 fossil discovery in Canada of fish with "intermediate" features -- four finlike legs -- that allowed the creature to pull itself through shallow water onto land. Scientists around the world cite this evidence as an important discovery in identifying the transition from ocean-dwelling creatures to land animals. By understanding and employing the principles of evolution, the discoverers of this fossil focused their search on layers of the Earth that are approximately 375 million years old and in a region that would have been much warmer during that period. Evolution not only best explains the biodiversity on Earth, it also helps scientists predict what they are likely to discover in the future.
Over very long periods of time, the same processes that enable evolution to occur within species also can result in the appearance of new species. The formation of a new species generally takes place when one subgroup within a species mates for an extended period largely within that subgroup, often following geographical separation from other members of the species. If such reproductive isolation continues, members of the subgroup may no longer respond to courtship from members of the original population. Eventually, genetic changes become so substantial that members of different subgroups can no longer produce viable offspring. In this way, new species can continually "bud off" of existing species.
Despite the overwhelming evidence supporting evolution, opponents have repeatedly tried to introduce nonscientific views into public school science classes through the teaching of various forms of creationism or intelligent design. In 2005, a federal judge in Dover, Pennsylvania, concluded that the teaching of intelligent design is unconstitutional because it is based on religious conviction, not science (Kitzmiller et al. v. Dover Area School District). NAS and IOM strongly maintain that only scientifically based explanations and evidence for the diversity of life should be included in public school science courses. "Teaching creationist ideas in science class confuses students about what constitutes science and what does not," the committee stated.
