The Evolution of Photosynthesis

The Public Science Lectures October 19, 2010 Belmont Public Library, Belmont MA

Tanja Bosak, Ph.D., Assistant Professor,and Alexander Petroff, Ph.D. candidate, Department of Earth, Atmosphere and Planetary Sciences, Massachusetts Institute of Technology NOTE: as of 2011, Alex Petroff, Ph.D., is a Presidential Fellow, Center for Physics & Biology, Rockefeller University.

Professor Tanja Bosak and Ph.D. candidate Alexander Petroff describe a unique scientific investigation of the sedimentary record of early Earth. Their research reveals how photosynthesis and life emerged in the ancient chemical environment of this planet. Dr. Bosak and Alex Petroff describe how scientists are reconstructing the complex co-evolution of environment, photosynthesis, microbes and minerals. And they explain the substantial challenges of analyzing the ancient remnants of photosynthesis and its relationship to other natural processes billions of years ago. The joint lecture provides important details of the controversies generated by different interpretations of this ancient process.

Professor Tanja Bosak received the 2007 Subaru Outstanding Woman in Science Award. The Award is presented to a woman that has impacted the field of the geosciences in a major way based on Ph.D. research.

Alexander Petroff (at the time of this lecture) is doctoral student at MIT’s department of Earth, Atmospheric, and Planetary Science. His background is in mathematics and physics. His research focuses on how the complex and intricate patterns in the natural world arise from simple physical law.

Some background:

A Look Back in Time By linking the odd geometry of bacterial growths to photosynthesis, researchers may have a new way to study Earth’s oldest fossils.

Bacterial Growths May Offer Clues about Earth’s Distant Past. Deciphering the few clues about ancient bacterial life that are seen in preserved rocks is very difficult, but researchers from MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS) and the Russian Academy of Sciences may have found a way to glean new information from the fossils. Specifically, they have linked the even spacing between the thousands of tiny cones that dot the surfaces of stromatolite-forming microbial mats — a pattern that also appears in cross-sectional slices of stromatolites that are 2.8 billion years old — to photosynthesis.

abstract for article on this research by Petroff, Bosak, et al. (2010), in Proceedings of the Natl Academy of Science: Biophysical basis for the geometry of conical stromatolites