Many of our physical traits are remnants of our ancestors, features that once played a crucial role in survival but have since become obsolete. While humans no longer need to scavenge for food or swing through trees, our bodies still carry traces of an evolutionary past.
Goosebumps: A Relic from the Past
Have you ever wondered why we get goosebumps? This reaction, inherited from our mammalian ancestors, originally helped animals retain body heat. When cold, tiny muscles attached to body hair contract, causing the hairs to stand upright and create insulation, much like a bird puffing up its feathers in winter. While no longer necessary for warmth, this response remains a visible reminder of our evolutionary history.
A Tendon That Links Us to Primates
One of the clearest signs of human evolution is hidden in your wrist. The palmaris longus, a muscle once essential for tree-dwelling primates, is gradually disappearing in humans. This muscle and its associated tendon helped arboreal species, like lemurs and monkeys, grip branches as they moved through treetops. However, since humans and ground-dwelling apes no longer rely on this function, evolution has slowly phased it out.
Are You Part of This Evolutionary Change?
Around 10-15% of people today no longer have this tendon, proving that human evolution is still at work. Want to check for yourself?
1. Place your forearm flat on a table with your palm facing up.
2. Touch your pinky finger to your thumb.
3. Slightly lift your hand off the surface.
If you see a raised band in the center of your wrist, you still have the palmaris longus tendon, a direct link to your primate ancestors. If not, congratulations! You’re part of a subtle but ongoing evolutionary shift.
The presence (or absence) of this tendon is a fascinating reminder that human evolution isn’t just history, it’s still happening today.
