Question

Vertebrates developed about 550 million years ago. the oldest vertebrate fossils are those of _____ with no jaws.

Answer 1

oldest vertabrate fossils were fish with no jaws

Answer 2

Vertebrates developed about 550 million years ago. The oldest vertebrate fossils are those of FISH with no jaws. These early jawless fish did not have paired fins and their bodies were covered with heavy, bony scaled, but their skeletons were made of cartilage. For the next 50 million years, they were the only vertebrates.