Special Earth-Science Review Issue Edited by ODU's Nora Noffke
Old Dominion University geobiologist Nora Noffke is the guest editor of a special issue of the journal Earth-Science Review exploring geological evidence of Earth's earliest life.
The title of the issue is "Microbial Mats in Earth's Fossil Record of Life: Geobiology."
Noffke, who has been widely recognized in recent years for her research about early life forms, also wrote one of the issue's articles: "The Criteria for the Biogeneicity of Microbially Induced Sedimentary Structures (MISS) in Archean and Younger, Sandy Deposits."
The issue, published this fall, includes an introduction by the eminent biologist Lynn Margulis, whose landmark work four decades ago helped to explain the evolution of microorganisms on the early Earth. Margulis is a professor in the Department of Geosciences at the University of Massachusetts.
Noffke was particularly pleased by this introduction, which resulted from a chance meeting of the two women at Oxford University last summer. "She enthusiastically agreed to write it, and found some really nice words to say about my work," Noffke said.
An ODU associate professor of ocean, earth and atmospheric sciences, Noffke also is a visiting scholar with the Carnegie Institution of Washington, D.C. (CIW). Her work there is funded by the NASA Astrobiology Institute Carnegie and sponsored by Robert Hazen, a researcher at the CIW's Geophysical Laboratory who is well known for his scientific investigations concerning the origin of life.
Noffke's research has shown that MISS, a term that her work has helped to coin, are reliable geobiological evidence of early life on Earth. The life forms colonized sandy coasts of Earth around 3 billion years ago during the Archean Age.
The work provides an answer to a question scientists have grappled with: If tiny microbes were the earliest living organisms, where in the geological record can we possibly find irrefutable evidence of their existence?
Noffke's latest research in South Africa has turned up a virtual treasure trove of geological samples supporting her case that the microbial mats we see today covering tidal flats were also present as life was beginning on Earth.
The mats, which are woven of cyanobacteria, can cause unusual structures in the sand beneath them. Noffke has identified two dozen such structures caused by present-day microbial mats, and has found corresponding structures in the geological record dating back through the ages.
Margulis wrote in the introduction that she was "thrilled" about the possibility that MISS examples discovered by Noffke may provide evidence for the earliest date for the appearance of oxygenic photosynthesis--about 3 billion years ago. She added, "We are enthusiastic about the fabulous color photos that document the striking similarity between modern and billions-of-years-old microbial mats" provided by Noffke.
In the introduction, Margulis notes that the work of Noffke and of others whose articles appear in the special MISS issue, has allowed her to look at some rock samples "with new eyes."
In 2007, Noffke was elected a Fellow of the Geological Society of America in recognition of her research establishing MISS as evidence of the earliest life on Earth. She also won the 2007 James Lee Wilson Award of the Society of Sedimentary Geologists, which is given annually to recognize international excellence in marine geology by a young scientist.