Tomaso was a postdoc working with myself, John Grotzinger and Victoria Orphan from 2008-10. His project at Caltech involved using NanoSIMS to measure the S isotopic composition of small kerogen inclusions in the 3.5 Ga Strelley Pool Chert stromatolites as evidence for microbial sulfur cycling on the early Earth. Tomaso received his Ph.D. from ETH in Zurich working with Judy McKenzie.