How did chordata evolve?

Answer 1

Chordata, the phylum that includes vertebrates, evolved from primitive deuterostomes around 500 million years ago. Key evolutionary advancements included the development of a notochord, dorsal nerve cord, pharyngeal slits, and a post-anal tail, which provided structural support and facilitated movement. These features likely offered advantages in aquatic environments, leading to the diversification of early chordates into various lineages, including the ancestors of fish, amphibians, reptiles, birds, and mammals. Over time, evolutionary pressures and adaptations contributed to the vast diversity seen in chordates today.