Fossil evidence for the first chordates
However, fossil evidence in the Burgess shales (550 million years ago) included a finned or backboned swimming animal similar to the living lancelet called a Pikaia and was the predecessor to a group of fish-like animals that were jawless (apart form modified parasitic forms) and consequently could only feed on micro-organisms and small animals. These animals belong to the class
The missing link: The chordate fossil found in the Flinders Ranges.