No, sharks are not tetrapods. Tetrapods are a group of animals that have four limbs, including amphibians, reptiles, birds, and mammals. Sharks, on the other hand, belong to a class of fish known as Chondrichthyes, which have a skeleton made of cartilage instead of bone and are characterized by their fins and gills.
Sharks evolved much earlier than tetrapods; they have been around for over 400 million years, long before the first tetrapods appeared around 360 million years ago. While both tetrapods and sharks fall under the larger category of vertebrates, the key distinction lies in their limb structure. Sharks have pectoral and pelvic fins adapted for swimming, not the four limbs associated with tetrapods.