VERTEBRATA
Organisms With Segmented Backbones
[© Randall, J.E.]
Chapter Outline
- Description of Vertebrata
- Classification of Vertebrata
- Cyclostomata (Ch. 32)
- Chondrichthyes
- Batoidea
- Chimaeriformes
Links to external sites will appear in pop-up windows.
Vertebrata is a clade within the subphylum Craniata. It contains those organisms with a vertebral column or human-like spine.
The last page of the previous chapter began to introduce vertebrates with the jawless hagfishes and lampreys. Hagfishes do not have backbones that appear to be like other vertebrates so it was previously thought that they were a sister group of the vertebrates, not actual vertebrates themselves. More recent genetic analysis suggests that hagfishes have just lost some of their vertebrate traits but are actually genetically similar enough to warrant being placed in Vertebrata.
This chapter, and the following five chapters explore all the remaining vertebrates. Every organism from here on is not only a vertebrate but a vertebrate with jaws, which places them in in the clade Gnathostomata. The focus of this chapter is on the class Chondrichthyes which contains jawed vertebrates with skeletons made of cartilage instead of bone.
Resources:
|
| [ Previous Page ] | [ Next Page ] |