Chapter 25 - Theoretical and Experimental Ichnology of Mobile Foraging

Abstract

Trace fossils provide critical indications of the early evolution of sensory systems, and of the evolution of behavioral responses to environmental heterogeneity. Foraging theory provides a useful conceptual framework for understanding the behaviors represented by foraging traces. This chapter has developed a model for foraging trace formation that incorporates environmental heterogeneity, as well as contact and distance chemoreception. This model produces a wide range of trace morphologies from the same basic behavior. Changes in the occurrence of trace fossil types over time, in particular during the Precambrian–Cambrian transition, may be largely a consequence of the development of spatial heterogeneity on the ocean floor rather than the development of new and more complex behaviors. Ecologists have extensively studied the patterns and controls of organism movement in terrestrial environments and, to a much lesser extent, in marine environments. The chapter also examines the implications of modern theoretical and experimental studies of animal movement to ichnology. It also presents a discussion of the implications of these concepts for the early evolution of traces.