Intelligent people have more zinc and copper in their hair.
233
Awarding people money for doing well in IQ tests causes them to score better, $10 increased people's score by an average of more than 20 IQ points. IQ tests don’t just measure intelligence - they also measure effort.
9
There’s a bonobo named Kanzi who has learned to build a campfire and cook his own food.
8
Dolphins have names for one another.
18
In the US, people can be rejected from joining the police force if they are too intelligent.
45
Intelligent men tend to be more sexually faithful.
31
You can only remember 4 things at a time.
31