Researchers from MIT and Brigham and Women's Hospital in Boston say a porcupine's quills have the ability to puncture skin easily and could lead to more efficient and less painful shots, while their trickiness to remove could lead to better medical adhesives.

A porcupine has about thirty thousand quills on its back, and the tip of each quill has a backward-facing barb enabling it to penetrate tissue with ease.

Once in the tissue, the barbs keep it in place. The study was published in the Proceedings of the National Academy of Sciences.