I am an observational astronomer interested in the formation and evolution of galaxies across cosmic history. I use imaging and spectroscopy from the most advanced telescopes in the world, including the recently launched James Webb Space Telescope (JWST), to understand how the first galaxies formed and what physical mechanisms control galaxy growth over time. The population of galaxies at very early times shortly after the Big Bang looks very different from the present-day galaxy population. I am working to characterize how the galaxy population changes over time and to identify the physical mechanisms that drive these changes and govern galaxy growth, including the movement of gas into and out of galaxies and the impact of energy produced in supernova explosions when stars die. I specialize in the study of the chemical makeup of galaxies, determining the abundance of various elements (e.g., hydrogen, oxygen, carbon, nitrogen). Since essentially all elements except hydrogen and helium were produced by nuclear fusion in the cores of stars, the chemical fingerprint of a galaxy informs us about its formation and growth history. The results tell us about the origin of galaxies like the Milky Way in which we live.