This project answers a simple question: why are there so few fossils in sediment cores from Antarctica?s continental shelf? Antarctica?s benthos are as biologically rich as those of the tropics. Shell-secreting organisms should have left a trail throughout geologic time, but have not. This trail is particularly important because these organisms record regional climate in ways that are critical to interpreting the global climate record. This study uses field experiments and targeted observations of modern benthic systems to examine the biases inflicted by fossil preservation. By examining a spectrum of ice-affected habitats, this project provides paleoenvironmental insights into carbonate preservation, sedimentation rates, and burial processes; and will provide new approaches to reconstructing the Cenozoic history of Antarctica. Broader impacts include graduate and undergraduate research and education, development of undergraduate curricula to link art and science, K12 outreach, public outreach via the web, and societal relevance through improved understanding of records of global climate change.
As earth climate warms and ice sheets melt, more and more land cover will be exposed along the Antarctic continent. What influence will greater imput of terrestrial materials have on near shore marine environments? Can we better recognize similar episodes in earth history from the fossil record? This research project identified key aspects of "fossilization" processes in a setting associated with such an ice-free landscape, namely the Taylor Dry Valley in McMurdo Sound. In 2006 and again in 2008, research divers collected numerous sediment cores, deployed/retrieved experimental arrays, and conducted photo/video transects at primary research site, Explorers Cove, which is one of the few places in Antarctica that is readily accessible for such research. Our group helped determine the fate of wind-swept and meltwater-deposited sediment to the seafloor and identified the role of various organisms in disturbing surface sediment and thus influencing the fossil record. We also developed molecular markers for one key group of fossil-producing unicellular organisms (i.e., foraminiferan protists), which can now be used in future studies of "ancient DNA" in this and other Antarctic marine environments. During the course of this work, approximately 1,000 students and adults were directly addressed by participating scientists through school visits and public outreach talks.
