The ability of our skeletons to move with both flexibility and stability can be traced back to ancient jawed fish. Scientists studied modern cartilaginous fish, such as sharks and skates, and compared them to their jawless counterparts, like lampreys. They discovered that synovial joints — lubricated, cavitated structures found in most vertebrates — first appeared [...]from SciTechDaily https://ift.tt/VZxuUN8
