The genomic revolution has enabled researchers to assess cell-by-cell genetic variations, but very few techniques exist to measure cell-by-cell metabolic variations, a more powerful way to understand cell responses to changing environmental conditions. Researchers from Stony Brook University's School of Marine and Atmospheric Sciences (SoMAS), led by Gordon T. Taylor, Ph.D., demonstrated that Raman microspectroscopy can accurately measure cell-by-cell variations in growth rates of the bacterium E. coli grown in a broth medium. They validated the Raman-based technique against independent traditional population-based spectroscopic and mass spectrometric measurements.