It’s not just their teeth and jaws that people find intriguing. It’s also their funky shapes and unique skeletal makeup that capture attention. Unlike humans and most land animals, sharks have mineralized cartilage skeletons instead of bones. This allows them to move at unbelievable speeds through the water. Since cartilage weighs less than bone and is less dense, sharks can bend, swim, and maneuver in the ocean much differently than their bony fish counterparts.