The word vertebrate derives from the Latin word vertebratus (Pliny), meaning joint of the spine. A similarly derived … See more

All vertebrates are built along the basic chordate body plan: a rigid axial endoskeleton (vertebral column and/or notochord) running along the length of the animal, dorsal to the gut tube, with a hollow dorsal nerv… See more

In addition to the morphological characteristics used to define vertebrates (i.e. the presence of a notochord, the development of a vertebral column from the notochord, a dorsal nerve cord, pharyngeal gills, a pos… See more

Originally, the "Notochordata hypothesis" suggested that the Cephalochordata is the sister taxon to Craniata (Vertebrata). This group, called the Notochordata, was placed as sister group to the Tunicata (Urochordata… See more

There are several ways of classifying animals. Evolutionary systematics relies on anatomy, physiology and evolutionary history, which is determined through similarities in anatomy and, if possible, the genetics of organisms. … See more

The number of described vertebrate species are split between tetrapods and fish. The following table lists the number of described extant species for each vertebrate class as estimated in the IUCN Red List of Threatene… See more