Last week I attended the Geological Society of America’s 2017 meeting in Seattle with 6,500+ other delegates. I was an invited speaker for the ‘The Role of Silica in the Earth System: From Organisms to Global Biogeochemical Cycles’ session. Two synthesis talks (an excellent presentation by Dr Elizabeth Tower on The role of silica as a chemical sediment prior to the advent of metazoan biomineralization and my talk Plants and Silicon: a modern ecological perspective) were interspersed with brand new and recently published findings. The scope was broad, from microbial effects on early marine diagenetic Si cycling, role of sponges in chert formation, low temperature Si isotope exchange kinetics and fractionation, Si isotope records in marine sediments, to the evolution of biomineralization and Si accumulation in plants, the adaptive value of phytoliths (plant silica bodies), phytoliths in bryophytes and environmental impacts on the production of phytoliths in grasses.
The session pushed current boundaries of understanding in what we can learn using Si isotopes, how Si biogeochemical cycles might have been like before major biological Si users such as diatoms and plants appeared, how plant silicon uptake may have evolved using analysis of extant Si transporters and a discussion of what factors may have driven this evolution. I eagerly await the publication on phytolith production in bryophytes, as data for this plant group is lacking, which limits understanding evolution of plant silicon.
There were other talks and posters that were relevant to this session, mainly related to using phytoliths for palaeo-environmental reconstruction. Of particular note Dr Timothy Gallaher’s work on digitising grass silica cell phytoliths. There were several paleobotany sessions that I enjoyed and learning more about chemical analysis of preserved leaf waxes through a poster was memorable.
An unexpected highlight of the conference were many talks about innovative approaches of teaching geology (and environmental science), from virtual field trips, using mobile technologies to increase accessibility to geology fieldwork and involving natural history museums to enhance student experience and deepen learning.
I run a twitter feed for the module S112 Science: Concepts and Practice at The Open University, and asked students to vote for a talk at GSA which I would attend on their behalf. There was a tie between the two and I thought a talk on wine terroir would be of general interest, so I attended all three and prepared a summary of each for the students. I really enjoyed learning about Darwin’s contributions to geology (as opposed to his contribution to my field, biology). I found the talk on forensic geology from the interesting and informative Dr Laurance Donnelly, particularly his comments that the meticulousness with which scientists collect data can make it ideal for forensic evidence. The wine terroir talks also covered a new topic for me, and I thought the terroir wine tasting at the end was a great idea – such different taste from different soils and climates. I hope my summaries gave the students an idea of the breadth of geological applications.