The thumb is a symbol of character; can it bend backwards or forwards?
The majority of people's thumbs are straight, meaning they don't curve past the first knuckle.
Curved thumbs, on the other hand, can bend backwards past the first knuckle; this is called hitchhiker's thumb.
Does the form of your thumb tell us anything about who you are? If so, take this thumb personality test.
Your thumb's curve can reveal personality quirks similar to those associated with your foot arches, leg crossing patterns, or finger gaps.
If your thumb bends backwards past the first knuckle when you make a thumbs-up signal, that's your thumb shape.
The majority of people's thumbs are straight, meaning they don't curve past the first knuckle.