How far can you bend your thumb? 彎拇指同鄉

On New Year's night, my family and I went to have a Japanese feast, as feasting is our professional specialty (a bit redundant here, heh heh).

We of course ate more than just this huge plate of assorted sashimi.  Today's topic is not about the food! :D It's about the thumb-ups :D

Notice the thumb on the right? It's my dad's thumb. Notice how it bends?

During this dinner, my cousin (thumb on left) compared his thumb with my dad's and found out that my cousin's thumb doesn't bend like my dad's.

So I joined the battle and found out that I am truly my dad's daughter! My thumb bends even crazier than my dad's!! :D hahaha

After a bit of research online, I have the so called "Hitchhiker's thumbs".  it seems this is considered a recessive trait and not everyone can bend the thumb this far backwards :D

Maybe I can start a "Hitchhiker's thumbs association" (彎拇指同鄉會) :D Thumb Bender Unite!!

Here are my meaningful research materials:

http://udel.edu/~mcdonald/myththumb.html
http://en.wikipedia.org/wiki/Thumb#Variation