Trace Fossils From the Precambrian and Basal Cambrian

Certain worm-like configurations on rocks are recognized as shrinkage-crack infillings. Some genuine Precambrian trace fossils are briefly described. The early Cambrian contains a richer assemblage, including some distinctive and widespread form genera. The study of early trace fossils leads to conclusions not only on facies, but also on the evolution of behaviour and functional morphology in soft-bodied organisms.