Geobiology and paleobiogeochemistry researches the biological processes in deep time from the origin of life to mysterious ecosystems in Earth's earliest oceans, and events that may have spawned the evolution of complex multicellular life. To find clues about ancient ecosystems, the group studies molecular fossils of biological lipids (biomarkers) that can be preserved in sedimentary rocks for billions of years. Currently the group and students investigate the question why large, multicellular and active creatures appeared on Earth some 600 million years ago, and whether ancient oceans harbored a lost world of complex life that left no traces … possibly apart from a few obsolete molecules.