01/14/2026
The Palmaris Longus, and it’s one of the coolest examples of human evolution!
Here is everything you need to know about this "missing" muscle:
A Living Fossil: It’s a vestigial muscle we inherited from ancestors who used their arms for climbing and swinging.
The "Evolved" 15%: About 1 in 7 people are born without it in one or both arms.
No Weakness Here: If you don't have it, don't worry! Studies show there is zero loss in grip or pinch strength.
The Spare Part: Because it’s not essential, surgeons often use it as a "donor tendon" to repair other more important ligaments in the body.
Asymmetrical Odds: It’s totally normal to have it in your right arm but not your left (or vice versa).
The Test: Touch your thumb to your pinky and flex your wrist. See a tendon pop up? You’ve got it!
No tendon? You’re officially "highly evolved."
Check your wrist and tell us—are you Team Palmaris or Team Evolved? 👇
