Joining with the IGRM21 we will have a lecture by Prof. Paul F. Hoffman from the School of Earth & Ocean Sciences at the University of Victoria, BC, Canada. Formerly Professor of Geology at Harvard University, Paul is best known for his work on the Neoproterozoic Snowball Earth hypothesis.

He will present a lecture at 7pm on Thursday 25 February, related to Snowball Earth entitled:

“On the freshwater ancestry of marine primary producers: a snowball Earth legacy and implications for the pre-Cryogenian marine fossil record

Abstract: Molecular reconstruction suggests that many modern marine primary producers evolved in freshwater over most of their evolutionary history. This is surprising in view of the marine fossil record of cyanobacteria and algae back to at least 2.02 and 1.04 billion years ago, respectively. We can reconcile this apparent conflict by assuming that all modern organisms are derived from the survivors of Cryogenian snowball Earths, when phototrophy was limited to meltwaters, ice-covered lakes, and certain hot springs. This suggests that most pre-Cryogenian marine fossils represent stem groups, lacking direct descendants in living taxa.