The greatest animal radiation on Earth was promoted by a stable marine redox landscape

October 3, 2022By Tais W DahlOutreach, Publication

The greatest rise in marine biodiversity in all of Earth’s history surprisingly was not fuelled by ocean oxygenation. Instead, oceanic redox stability appears to have favoured increased ecosystem resilience and – ultimately – a massive rise in global biodiversity levels. Oxygen rise occurred later… PhD student Alvaro del Rey measured the uranium isotope composition of … Read More

Talk 6/7-2022: Dahl colloquium at IPM, Hamburg University

July 4, 2022By Tais W DahlUncategorized

July 6th, 2022 @ 17:15. Institut für Pflanzen und Mikrobiologie (IPM) is at Ohnhorststr. 18 in Klein Flottbek, a suburb of Hamburg. Tais will give a lecture for the Institute for Plants and Microbiology (IPM) at Hamburg University entitled: “Atmospheric oxygenation and climatic cooling during the early colonization of the terrestrial environment by plants”. The presentation will … Read More

Telling actual time in the rock record

May 5, 2022By Tais W DahlUncategorized

We have discovered a new method to tell time in the Geological record, using core scanning XRF analyses, which we have now applied to Cambrian and Ordovician rocks to refine the Geological Time Scale. The study, led by my PhD student Zhengfu Zhao, is now published in Nature Communications. The new method was first discovered … Read More

Field work in Malo Jezero, Mljet Croatia

November 21, 2021By Talk

[Croatia Nov 10,2021]: Abiotic aragonite precipitates in the modern seawater-fed lake and provide an opportunity to understand how trace elements gets into the carbonate rock record.

Podcast: The Geobiological History of Earth

October 18, 2021By Tais W DahlOutreach

Danish Science journalist Lone Frank interviews Tais W. Dahl about his research. Her podcast series is called “24 Questions to the Professor” and runs in Danish. The podcast went from the formation of the Earth, through microbial evolution and into the world of animals and the colonization of land. What drove environmental evolution and Earth’s … Read More

EarthTalks at GEOCENTER Denmark

April 23, 2021By Tais W DahlUncategorized

The Section for Geobiology at GLOBE has helped organizing the spring season of EarthTalks 2021, and we welcome interested students and researchers to participate over Zoom (link below). The talks will not be recorded. Earth Talks Lecture Series – Spring 2021 Friday afternoons 14:00-15:00 DK time (sharp) 23/4 – Prof. Sigur∂ur Gislason, University of Iceland The … Read More

Did land plants alter erosion rates on Earth?

March 28, 2021By Tais W DahlUncategorized

A discussion arises from the recent review article in Chemical Geology, where Tais W. Dahl and Susanne Arens concluded that land plants did not forever increase the physical weathering rates of the continental crust. This conclusion was reached from the records of preserved sediment rock volume and the timing of plant-assisted weathering as recorded in … Read More

The Carlsberg foundation supports field work in Siberia

January 27, 2021By Tais W DahlUncategorized

The Carlsberg Foundation is sponsoring field work led by Tais W. Dahl to Arctic Siberia, where an important climate catastrophe is recorded in marine sedimentary rocks. The expedition will bring back data and samples deposited in the oceans during a climate event that caused sulfidic anoxia to suddenly expand in warming oceans and wipe out … Read More