Teaching about evolution in the framework of the nature of science is an important function. Because some people see evolution as conflicting with widely held beliefs, the teaching of evolution offers educators a superb opportunity to illuminate the nature of science and to differentiate science from other forms of human endeavor- or and understanding. However, it is important from the outset to understand how the meanings of certain key words in science differ from the way that those words are used in everyday life.
Think for example, of how people usually use the word "theory." Someone might
Science has many other powerful theories besides evolution. Cell theory says that all living things are composed of cells. The heliocentric theory says that the earth revolves around the sun rather than vice versa. Such concepts are
Sometimes scientists themselves use the word "theory" loosely and apply it to
Glossary of Terms Used in Teaching About the Nature of Science
Fact: In science, an observation that has been repeatedly confirmed.
Law: A descriptive generalization about how some aspect of the natural world
Hypothesis: A testable statement about the natural world that can be used to
Theory: In science, a well-substantiated explanation of some aspect
As with all scientific knowledge, a theory can be refined or even replaced by an
The geocentric theory that the sun revolves around the earth was replaced by the heliocentric theory of the earth's rotation on its axis and revolution around the sun. However, ideas are not referred to as "theories" in science unless they are supported by bodies of evidence that make their subsequent abandonment very unlikely. When a theory is supported by as much evidence as evolution, it is held with a very high degree of confidence.
In science, the word "hypothesis" conveys the tentativeness inherent in the common use of the word "theory.' A hypothesis is a testable statement about the natural world. Through experiment and observation, hypotheses can be supported or rejected. At the earliest level of understanding, hypotheses can be used to construct more complex inferences and explanations.
Like "theory," the word "fact" has a different meaning in science than it does in common usage. A scientific fact is an observation that has been confirmed over
Finally, "laws" in science are typically descriptions of how the physical world
Those who oppose the teaching of evolution often say that evolution should be taught as a "theory, not as a fact." This statement confuses the common use of these words with the scientific use. In science, theories do not turn into facts through the accumulation of evidence. Rather, theories are the end points of
Unit One Background
Last updated: February 24, 2015