13 science-backed signs you're smarter than average

How do you know if someone's smart?

Without administering an impromptu IQ test, there are certain clues you can use to gauge a person's relative intelligence.

We combed through decades of scientific research and highlighted 13 surprising signs of braininess.

Keep in mind, however, that "intelligence" is often measured through tests that have been widely criticized for putting certain social groups at a disadvantage and for minimizing the importance of creativity. Psychologists are constantly finding newer, more effective ways to measure cognitive ability - meaning the signs are ever-evolving.

Additional reporting by Chelsea Harvey.