Chapter 32.3, Problem 1R

Summary Introduction

To review:

The synapomorphies, which characterize the vertebrates and chordates.

Introduction:

The phylum Chordata includes three subphyla, which are vertebrata (Craniata), Cephalochordata (lancelets), and Urochordata (tunicate). On the other hand, the vertebrata includes five classes, which are fish, amphibians, reptiles, birds, and mammals. The animals under this subphylum are morphologically quite distinct. Their common ancestry is evident only during their respective embryonic stages.