Public acceptance of evolution

At the Astronomy program, we had a one-page handout that provided some historical context for the topic. Today, many find it hard to understand why it should have taken more than 150 years for the heliocentric theories of Copernicus, the careful observations of Galileo, and the ingenious calculations of Kepler to gain widespread acceptance. But beliefs die hard, and beliefs that are central to man's self-image and his perceived role in the universe are especially resistant to challenge. To provide some modern perspective, the handout reminded readers that Darwin's theory of evolution was published 150 years ago and has been reinforced by a steady stream of scientific evidence ever since then. Nevertheless, a majority of people in the United States still do not accept the validity of evolution, and major elements of the world's great religions continue to resist incorporating evolutionary science into their belief systems.

This assertion apparently surprised and dismayed a number of people in the audience, but it is supported by a number of studies and polls that have been made regarding the public acceptance of evolution in the U.S. and elsewhere. The most widely publicized study (from 2005) compared results in 34 different countries. As the graph shows, the U.S. ranked 33rd, ahead of only Turkey, in public acceptance of evolution. Over the last 20 years, those in the U.S. expressing belief in evolution declined from 45% to 40%, while those rejecting it outright declined from 48% to 39%, with the rest not sure. So 60% of Americans either reject or are skeptical of evolution.

The same study also cites a survey that used different response choices, but came up with essentially the same result: "A dichotomous true-false question format tends to exaggerate the strength of both positions. In 1993 and 2003, national samples of American adults were asked about the same statement but were offered the choice of saying that the statement was "definitely true, probably true, probably false, definitely false," or that they did not know or were uncertain. About a third of American adults firmly rejected evolution, and only 14% of adults thought that evolution is "definitely true." Treating the "probably" and "not sure" categories as varying degrees of uncertainty, ~55% of American adults have held a tentative view about evolution for the last decade."

Other polls look even worse. According to an excellent article in the Economist, "In the United States a Gallup poll conducted last year found that only 14% of people agreed with the proposition that “humans developed over millions of years”, up from 9% in 1982."

Explanations usually focus on the much stronger strain of religious fundamentalism in America, especially when compared to Western Europe, and on the significant, but often unacknowledged, cultural gulf that exists between the two coasts, on the one hand, and the vast middle stretches of the country, on the other. It may be dismaying, but it should not be surprising.