Trace Fossil Geometry

The ichnofossils Treptichnus and Multina provide clues about the development of behavior in burrowing metazoans. A particular behavior type may be condensed and superimposed on the original burrowing pattern of programmed behavior. For example, a fine scale sinusoidal pattern may be superimposed on a large scale sinusoidal pattern. Side to side small scale branching may be superimposed on side to side main burrow elongate loops. Both burrow types are convergent behaviors with the same function, namely, more thorough deposit feeding in deep water sediments and/or low organic content sediments where the animal is required to thoroughly sift the sediment and must avoid reprocessing sediment that has been already fed upon.