What is the oldest vertebrae?

The oldest known vertebrate is a species of jawless fish called Myllokunmingia, which dates back to around 518 million years ago during the Cambrian period. Fossils of this creature provide insights into early vertebrate evolution, showcasing characteristics such as a notochord and primitive structures resembling gills. Another notable ancient vertebrate is Haikouichthys, also from the Cambrian, which is considered one of the earliest examples of a more advanced vertebrate. These early vertebrates played a crucial role in the evolutionary history of fish and, subsequently, all vertebrates.