What role did muckrakers play in the progressive era?

Muckrakers exposed big industries such as meat packaging (Sinclair), Standard Oil Company (Tarbell). This opened the eyes of Americans not only to the conditions of the factories, but the harsh labor (long work days and dangerous conditions). The impact of exposure led Americans seeking the need for reform. Muckrakers brought to attention information that some may have wanted to keep under wrap. They were called muckrakers since they brought issues they found about society to light and created controversy.

Democracy and darwinism would be my answer.