Zach studies two of the major transitions in the history of life as part of the Knoll Group: the origins of replicating molecules and the origins of the eukaryotic cell. For his PhD project, he discovered two new sources of microfossils in the 1.4 billion year old Belt Supergroup of Montana. The assemblages include unique specimens of Tappania plana, one of the earliest examples of complex eukaryotes and the first such fossils reported from Laurentia. Read more about Zachary Adam
Felix is a microbial biogeochemist studying the lipid "fingerprints" of archaea and bacteria ‒ microorganisms that control the cycling of elements such as carbon and nitrogen on our planet. His research focuses on reconciling microbiological lab experiments with geochemical observations from the modern ocean to improve the application of microbial lipids for the reconstruction of past environments. Read more about Felix Elling
I’m interested in connections between the geologic and biospheric carbon cycles. Specifically, my work aims to understand how processes occurring in river basins transfer carbon between these two cycles in order to regulate atmospheric CO2 concentrations over geologic timescales. To do so, I combine a suite of isotope geochemistry techniques (including compound-specific isotope measurements and novel reaction monitoring methods) with inverse models, satellite products, and geospatial analysis. My current projects include analysis of multi-year time-series samples from the Ganges-Brahmaputra and Congo Rivers, high-frequency samples from mountainous rivers in Taiwan, isotope analysis of bacteriohopanepolyols in continental shelf sediments, and development of the Ramped PyrOx radiocarbon instrument. I'm additionally working on reconstructing the mechanisms that control Cenozoic CO2 variability using inverse modeling methods.
Post-Doctoral Fellow Perez-Mercader Lab, Rowland Institute
Yuandu Hu studied in Huazhong University of Science and Technology in Wuhan China and earned his PhD in June 2013, majoring in Polymer Chemistry and Physics. He focused mainly on the fabrication of functional soft materials (e.g. shape controllable microgels and stimulus-responsive photonic crystal microparticles) by combining microfluidic techniques and self-assembly of colloidal particles together. Prior to joining the Perez-Mercader group in September 2014, he spent one year in the University of Notre Dame in Indiana as a postdoctoral research associate. His work at Notre Dame dealt mainly with the fabrication of Janus microgel particles and self-propelling materials to mimic mircoorganisms' motion behavior.
Jenan is a microbial biogeochemist and oceanographer interested in the important connections between microbial ecology and marine biogeochemical cycling.
Originally from Wisconsin, Jenan obtained a B.A. in biology and chemistry from Ripon College in Ripon, WI. Subsequently she earned her PhD from Scripps Institution of Oceanography in La Jolla, CA, studying chemical oceanography in the lab of Dr. Lihini Aluwihare. Her thesis research focused on the use of molecular signatures to investigate microbial metabolic diversity and function in marine environments, and specifically targeted two important classes of microbial lipid biomarkers: bacterial hopanoids and intact polar diacylglycerols. Read more about Jenan Kharbush
I study Earth’s great ice sheets using geophysical data and mechanical models. Most Antarctic ice loss occurs as ice slides off the continent into the sea. Understanding ice sheet sliding is therefore essential to understanding the contribution of ice sheets to past, present, and future sea level rise. Despite this importance, most ice sheet models still rely on ad-hoc sliding laws that omit important physics and exhibit pathological behaviors. My recent work has employed more physically realistic frictional sliding laws. Such sliding laws describe the resistance to sliding provided by a finite strength ice--bed interface. The difference between frictional sliding laws and traditional, unbounded sliding laws has important consequences in the context of global change: if the ice--bed interface has a finite strength, then its capacity to resist the forces driving ice loss is fundamentally limited. My primary research objective is to quantify the processes that govern the strength of the ice--bed interface.
Two themes distinguish my scientific work. First, I exploit an interplay between observation and theory. My science always starts with observation. My workflow then builds simple models from simple observations before iterating and creating a hierarchy of complexity. Second, my work informs the study of climate systems but is based in solid mechanics, earthquake science, and geophysics. This crossing of disciplinary boundaries allows me to leverage the best physical insights from diverse fields towards tackling new challenges in ice sheet physics.
Nagissa is broadly interested in microbial degradation of organic compounds including anthropogenic pollutants as well as natural organic matter. Nagissa completed her B.Sc. in Integrative Biology from the University of Toronto in Canada. Subsequently, she earned her PhD at McMaster University in Canada where she employed a variety of tools, ranging from isotope geochemistry to high throughput sequencing, to investigate microbial communities in petroleum impacted environments. This research involved assessing microbial carbon sources using natural abundance radiocarbon analysis of lipid biomarkers and subsequently linking degradation to specific taxonomic groups. Read more about Nagissa Mahmoudi
Before joining the Knoll Group, Drew received a B.S. in Biological Sciences from Cornell University and a Ph.D. in Geosciences from Virginia Tech. As a paleontologist and geobiologist, his work focuses on fossils of complex eukaryotes in the late Neoproterozoic-early Paleozoic interval (~1000-450 Ma) of the geologic record. By studying the paleobiology and paleoenvironments of these fossils, his work aims to understand the rise of animal life and its impact on the Earth system.
Post-Doctoral Fellow Perez-Mercader Lab, Rowland Institute
Kaixuan Ren earned her Ph.D degree in polymer chemistry and physics from Changchun Institute of Applied Chemistry, Chinese Academy of Sciences in July 2015. Her research focused on the design and synthesis of polypeptide-based copolymers, fabrication of hydrogels as 3D scaffolds for cartilage tissue engineering. After her PhD, she joined the Prof. Perez-Mercader’s group as a postdoctoral fellow in November 2015.
I received my PhD from the University of California, Santa Barbara; my MS from University of California, Los Angeles and my B.S. in Geology from Louisiana Tech University. I joined Andy Knoll's Lab in August of 2015 as a NASA Astrobiology Postdoctoral Fellow. Read more about Leigh Anne Riedman
Post-doctoral Fellow Junior Fellow of the Society of Fellows Knoll - Pierce - Lauder Groups
Elizabeth is both a paleontologist and biological oceanographer. She is broadly interested in the evolution, structure, and function of ocean ecosystems. She uses a multi-proxy approach to study how the open ocean ecosystem has changed through time, with a focus on how it has responded to climate and biotic events in the past. Elizabeth works primarily with ichthyoliths, microfossil fish teeth and shark scales found in deep-sea sediments world wide, which preserve an unparalleled record of fish diversity, abundance, and community structure through geologic time.