The growth vector in trace fossils: Examples from the Lower Cambrian of Norway

Abstract

The Dividal Group of northern Norway includes both Vendian and Lower Cambrian sequences. Trace fossil assemblages in the Lower Cambrian part of the group generally indicate endobenthic communities dominated by deposit‐feeding animals. At one level, however, an unusual succession of trace fossils occurs that includes Diplocraterion parallelum and a conical, branching shaft herewith named Altichnus foeyni. Both forms show features recording the growth of the tracemaking animals. Suspension feeders are probably indicated. D. parallelum is exclusively protrusive, which is suggested to be a primitive behavioral feature. The trace fossil also shows random orientation; well‐developed parallel orientation of D. parallelum does not seem to have been recorded before the Triassic. This assemblage represents the earliest documented example of the Glossifungites ichnofacies.

Key words:

• trace fossil
• ontogeny
• Glossifungites ichnofacies
• Cambrian
• Norway