How rare is that?
👅 Can roll their tongue
70% of people
About 70 of every 100 people are in this group. Not purely genetic, whatever your biology teacher said.
Each figure stands for one percent of the group. The share is a rounded estimate from public surveys and published studies; the group it refers to is "people", which is not always the whole world.
Tick it on the Ladder → and combine it with everything else about you