Evolution syndrome is the tendency of some people to insist compulsively that human evolution from animals must somehow be true, and to spend nearly all of their time pushing that belief on others. It is reflected on the internet by people who devote over 90% of their edits and postings to pushing their belief in evolution and insisting on censoring or demonizing alternative views of the issue. They are particularly against teaching any alternative theories to children in school, sometimes claiming that this will harm children's critical thinking. A childish insistence on last wordism is a common characteristic of evolution syndrome.

Sufferers of evolution syndrome tend to be college students or graduates who wanted to excel in math or physics, but lacked the ability or work ethic to do so. They are frustrated "wannabees" with respect to academic recognition. But they find that liberals will praise their intelligence if they promote evolution. This is analogous to a struggling ball player deceitfully turning to steroids to enhance his performance, and thereby make it to the "Big Leagues."