unseenwildlife on Instagram: "Sharks are extraordinary cartilaginous fish that have patrolled the world’s oceans for over 400 million years, predating even the earliest dinosaurs. Unlike most fish, their skeletons are made of lightweight, flexible cartilage rather than bone, which, combined with their oily livers, allows them to remain buoyant and highly maneuverable. They possess an array of highly specialized senses, including the ability to detect the tiny electromagnetic fields produced by t