Why is it that when you fold your fingers down, they are all the same length, but when you put them straight up they are all different lengths?

Mine don’t. But can you touch your elbows behind your back?

@math_nerd : Uhm, it depends on where my other elbow is. Let me take a picture of my own fingers.

I just tried this. When you look at your fingers pressed onto your palm, they do land at the same place, but if you roll your hand forward (so that it looks like your fist is going to punch you in the face) you will see that your knuckles are not at the same height (level to the ground). It’s the actual length of the bones and the placement of the bones relative to each other that make this illusion occur.

Mine are not the same length either way.My thumb sits high on my hand too so my fist looks odd.

It has to do with the placement of joints in your hand. Just yesterday, my hubby was demonstrating to my 6 year old the strange and funky things hands can and can’t do because of the amazing way they work. If you completely relax your hand and then grab around the wrist and squeeze you can see your fingers involuntarily contract. If you make a fist and then put it on a table with your palm down but with only your ring finger extended out you can not lift that finger.

Our fingers curl into a linear conclusion because that is the most effective grasping formation. If it didn’t do this, our grip wouldn’t be as good.