Chapter 34.4, Problem 1CC

Summary Introduction

To determine: The origin and derived traits of the tetrapods.

Concept introduction:

Tetrapods originated about 400 million years ago in the Devonian period. They evolved from the Sarcopterygii the “lobe finned fishes”. The early tetra pods have limb present in place of the pelvic and the pectoral, but still used to have the aquatic mode of life. They have various derived characters, like the separated head from the body in the presence of the neck and the presence of the pelvic girdle bone in them.