This particular one involves a list of countries and their average IQs, and it even cites a research study as its provenance.

When IQ scores are plotted on a graph, they typically follow a bell-shaped curve, often called the bell curve. The peak of ...

As IQ scores were not available for most of the presidents, Simonton used a "historiometric" approach to estimate their results: In the conventional approach to measuring IQ, Snopes.com notes ...

Is this legitimate? The chart is based on a 2006 study conducted by University of California, Davis psychologist Dean Keith Simonton, Snopes.com reports. As IQ scores were not available for most of ...