Which is the difference between the Paleozoic and Mesozoic eras?

Which is the difference between the Paleozoic and Mesozoic eras? O Animals lived in the water during the Mesozoic and on land in the Paleozoic. O The first birds emerged in the Paleozoic era while mammals first emerged in the Mesozoic. Many species of dinosaurs lived in the Mesozoic, but all died off in the Paleozoic. O Animal complexity increased during the Paleozoic while the first flowering plants appeared in the Mesozoic era