Appearance of Chordate Characters in Protochordates
In this article we will discuss about the gradual appearance of chordate characters in protochordates . The chordates exhibit different gradations of structural organisation from simple to complex. The protochordates including the three subphyla—Hemichordata, Urochordata and Cephalochordata—are the primitive members of the Phylum Chordata. All of them lack vertebral column and skull. They form an intermediate group between the non-chordates [...]