Vestigial Body Part…
It may sound dirty, but we promise it’s not! Vestigial body parts are those that our distant ancestors used—and thanks to evolution we no longer use—but for some reason they stuck around anyway (think wisdom teeth or the appendix).
The test to see if you have it is simple. Place both arms on a flat surface. Then raise your hands up while touching your pinky fingers to your thumbs. If you see a small band raise up, you still have the palmaris longus tendon. Pretty cool right?
This tendon is left over from when our evolutionary ancestors were walking on all fours. The tendon is missing in about 15 percent of all humans.
The palmaris longus isn’t the only thing that can still be found left behind from evolution. Humans and apes share jaw structure as well.
We have also inherited goosebumps from our ancestors.
It is believed that their initial purpose was to make our hair stand on end (back when we had a lot more of it!) to make us appear bigger when facing possible predators or other threats.