Available Positions

The Halevy group is searching for excellent, creative and highly motivated PhD students or postdoctoral researchers to study organism-to-ecosystem controls on stable isotope fractionation by microorganisms.

Microbial activity generates measurable isotopic fingerprints, which may be used to interrogate environmental conditions on the present-day and ancient Earth, as well as aspects of microbial physiology, ecology and evolution. For such uses, a robust and nuanced theoretical understanding of the controls on microbial isotope fractionation is necessary.

The approach will include development and interrogation of isotopically-enabled metabolic network computer models of microbial metabolisms (dissimilatory sulfate reduction, methanogenesis, methanotrophy, dissimilatory nitrate reduction, others). These models will be used to understand the controls on microbial isotope fractionation at the levels of a single organism, a microbial population, and an ecosystem. Ultimately, the models and the insights gained from them will be used to understand the isotopic composition of natural materials in present-day environments and in the sedimentary rock record, and the ways in which these can be confidently used to constrain (paleo)environmental conditions and biological activity.

Required: MSc or PhD in microbiology or isotope biogeochemistry / understanding of metabolism / experience in biochemical thermodynamics and kinetics / experience in metabolic network modeling / programming in Matlab (Python and/or R beneficial) / complete control of English / control of MSOffice software

Optional and preferred: experience in scientific writing / computational biology / systems biology / molecular cell biology / biological data science / control of Overleaf/LaTeX

The Halevy group is searching for excellent, creative and highly motivated PhD students or postdoctoral researchers for several experimental (bio)geochemistry investigations.

The chemical, mineralogical and isotopic composition of sediments and sedimentary rocks is used to interrogate, among other topics, the environmental conditions on the present-day and ancient Earth, aspects of microbial physiology, ecology and evolution. Such uses require a robust and nuanced understanding of the processes that produce and preserve measurable geochemical signals in sediments and sedimentary rocks, which can be gained in carefully controlled laboratory experiments.

Upcoming experimental investigations include:

1. Development of an experimental system for near-equilibrium precipitation of minerals, with the objective of constraining chemical and isotopic fractionation during near-equilibrium mineral formation, which has been a longstanding problem in isotope geochemistry.
2. Exploration of metastable iron minerals as catalysts of abiotic synthesis of organic molecules, with the objective of determining possible roles of such minerals in abiogenesis on early Earth.
3. Utilization of stable iron and sulfur isotope labeling to constrain mechanisms of iron-sulfide mineral formation in incubation experiments, with the objective of using the isotopic composition of such minerals to constrain (paleo)environmental conditions, microbial activity and evolution.

Required: MSc or PhD in geosciences (preference for isotope geochemistry), chemistry or microbiology / experience in geochemical lab work / complete control of English / control of MSOffice software

Optional and preferred: experience in scientific writing / experience in (bio)geochemical thermodynamics and kinetics /  programming in Matlab (Python and/or R beneficial) / control of Overleaf/LaTeX