Deep-sea hydrothermal vent systems & early life

Deep-sea hydrothermal systems appear to have been critical for the early evolution of life on Earth, yet their fundamental geobiology has barely been explored and remains poorly understood. We address this gap by studying the formation and preservation of biosignatures (e.g. rock fabrics and textures, mineral-organic associations, biogeochemical signatures) in modern and ancient hydrothermal sulfide deposits. This integrative approach yields important insights into the geobiology of the investigated hydrothermal sulfide systems. At the same time, it reveals how geo-bio interactions translate into geologically stable records. This strand of research is linked to the research field "Environmental nanomaterials & biomineralization" of the Geomicrobiology group, and important for understanding the origins of life on Earth and, perhaps, elsewhere in the universe.

Funding: DFG Emmy-Noether project (DU 1450/7-1); DFG research projects within the Priority Program (SPP) 1833 "Building a Habitable Earth" (DU 1450/3-1, DU 1450/3-2)

Biosignatures in Precambrian rocks & habitability of early Earth

The early evolution of life on Earth is closely tied to the fundamental nature of Precambrian surface environments. Understanding the co-evolution of Earth and its biosphere as a habitable world requires a profound knowledge on the earliest traces of life. However, the origin of purported biosignatures in Precambrian rocks is often ambiguous, as various sources come into question (biological vs. biotic) and the oldest rocks on Earth are increasingly subject to post-depositional alteration. We approach this problem by combining techniques from field geology, petrography and (organic) geochemistry to understand the formation and preservation of biosignatures within their geological context. This integrated view allows us to move towards a more solid record of early life on Earth and a better understanding of geo-bio interactions in deep time. Work on this project is in close collaboration with the research field "Iron Formations & Early Earth" of the Geomicrobiology group.

Funding: DFG Emmy-Noether research program (DU 1450/7-1); DFG research projects within the Priority Program (SPP) 1833 "Building a Habitable Earth" (DU 1450/3-1, DU 1450/3-2)

Early eukaryote and metazoan evolution

Eukaryotic primary producers are important constituents of the Phanerozoic biosphere. All evolutionary developments of this domain - from its first appearance (ca. 1.65 Ga) up to the Cambrian "explosion" of metazoan life - are still poorly understood. Commonly, these developments are seen as a direct consequence of the Proterozoic atmospheric oxygenation and related changes in global biogeochemical cycles. This simplified picture is likely due to an insufficient understanding of Precambrian ecosystem dynamics. We combine field and petrographic observations with biogeochemical analysis to unravel the geobiology of Mesoproterozoic to Cambrian ecosystems from various localities in Russia, Namibia and China. This approach will allow us to reconstruct the interactions between physical and biological processes in these environments and to gain deeper insights into the emergence of complex life.

Funding: DFG research project DU 1450/5-1, DFG research fellowship DU 1450/4-1