Trace Fossils in Evolutionary Paleoecology

Ichnologic data provide insights into evolutionary paleoecology, including the nature of Ediacaran ecosystems, diversification events such as the Cambrian explosion and the Ordovician radiation, and the colonization of various habitats including brackish-water and continental environments. In many cases, trace fossil evidence demonstrates much greater evidence of ecologic change than that revealed by body fossils alone. Trace fossil distribution through geologic time reveals a process of colonization, resulting from the exploitation of empty or under-utilized ecospace. Secular trends include increase in the diversity of biogenic structures, increase in the intensity of bioturbation, addition of new invaders, environmental expansion, and faunal turnovers.