Most U.S. high school biology teachers "fail to forthrightly explain evolutionary biology," finds an educator survey. And at least 13% "strongly support" teaching creationism.
Evolution, the inheritance of changed characteristics across generations, is the fundamental unifying concept underlying biology, as a National Research Council science education standards released in 1996 noted. That report said, "... 'biological evolution' cannot be eliminated from the life science standards."
But only 28% of the 926 teachers surveyed, "unabashedly introduce evidence that evolution has occurred and craft lesson plans so that evolution is a theme that unifies disparate topics in biology," according to the Science report by Michael Berkman and Eric Plutzer of Penn State. Most biology teachers belong to the "cautious 60%," who are "neither strong advocates for evolutionary biology nor explicit endorsers of nonscientific alternatives," the study says. As mentioned, 13% of respondents advocated biblical creationism or "intelligent design" creationism in biology class.
Our data show that these teachers understandably want to avoid controversy. Often they have not taken a course in evolution and they lack confidence in their ability to defend it. Their strategies for avoiding controversy are varied, but three were especially common and each has the effect of undermining science. Some teach evolutionary biology as though it only applies to molecular biology—completely ignoring macroevolution of species. At best, this approach sacrifices a rich understanding of the diversity of species. At worst it lends credence to the creationist claim that there is no evidence for one species giving rise to others.
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