All of the structurally identifiable latest Ediacaran and earliest Cambrian infaunal trace fossils represent shelters of animals feeding above the sediment surface. It is the case with the most complete and oldest radiometrically dated Precambrian–Cambrian transition strata along the Khorbusuonka River in northern Siberia, in the basal Cambrian succession at Meishucun in southern China, richest...

Osedax is a recently discovered group of siboglinid annelids that consume bones on the seafloor and whose evolutionary origins have been linked with Cretaceous marine reptiles or to the post-Cretaceous rise of whales. Here we present whale bones from early Oligocene bathyal sediments exposed in Washington State, which show traces similar to those made by Osedax today. The geologic age of these ...

Diffusion rates of numerous trace elements in bone at 20 °C were determined using laser-ablation inductively coupled plasma mass spectrometry analysis of experimentally induced diffusion profiles. Diffusivities are about 1 order of magnitude slower than current semiquantitative geochemical views and about 1.5 orders of magnitude faster than indirect radiotracer estimates. Intrabone volume diffu...

Zoophycos is one of the most complex and enigmatic trace fossils recorded in marine strata from Cambrian to Quaternary worldwide, which is invaluable for the study of Phanerozoic development of organism-environment interactions. Here we address and demonstrate the macroevolution of Phanerozoic Zoophycos by assembling 448 points in constructing the Phanerozoic Zoophycos database based on 291 pap...

An invertebrate ichnoassemblage from the Moenkopi Group (Spathian Ankareh Formation) at Diamond Creek in north-central Utah consists of Gordia marina Emmons, Helminthopsis hieroglyphica Wetzel and Bromley and irregular networks similar to Unisulcus. This is the first record of Gordia and Helminthopsis from the Moenkopi Group. This low diversity ichnoassemblage, consisting of simple grazing trac...