Anonymous Answered question November 12, 2020
Because of all the vertebrate have a nerve chord which is main character of chordate but all the chordate have not vertebral column which is main character of vertebrates.
Emily Changed status to publish January 31, 2018
chordata is divided to euchordata[vertebrata] and hemichordata[eg :balagnoglossus]. euchordata is divided to agnatha[jawless] and gnathostomata[have jaw] gnatho stomata is divided to picses and tetrapoda[reptilia aves mammalia and amphibia].So we can say that a hemichordate is chordata but not vertebrata. but vertebrata like picses mammalia..all are chordata
Emily Changed status to publish March 8, 2018