Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. The social effects of evolutionary thought have been considerable. As the scientific explanation of life''s diversity has developed, it has often displaced alternative, sometimes very widely held, explanations. Because the theory of evolution includes an explanation of humanity''s origins, it has had a profound impact on human societies. Some have vigorously opposed acceptance of the scientific explanation due to its perceived religious implications. This has led to a vigorous conflict between creation and evolution in public education, primarily in the United States.