No, sharks are not dinosaurs. While both sharks and dinosaurs have existed for millions of years, they belong to completely different groups of animals.
Sharks are part of the class Chondrichthyes, which includes all cartilaginous fish such as rays and skates. They have been around for over 400 million years, making them one of the oldest surviving species on the planet.
On the other hand, dinosaurs are part of the clade Dinosauria and are reptiles that existed during the Mesozoic Era, approximately 230 to 66 million years ago. Dinosaurs are characterized by certain skeletal features, including an upright posture and unique hip structures.
Although both sharks and dinosaurs coexisted millions of years ago, the two groups evolved separately and belong to distinct evolutionary lineages. Sharks survived several mass extinction events, including the one that wiped out the dinosaurs, which is why they continue to thrive today while dinosaurs do not.
In summary, while sharks and dinosaurs are often linked in discussions about prehistoric life, they are fundamentally different organisms with unique histories.