I will briefly present my early work in Trypanosoma cruzi, the causative agent of Chagas disease, and then present my current research in Experimental Microbial Evolution using the pathogenic yeast model, Candida albicans. We study the effects of oxygen concentrations and temperature in morphology and mitochondrial and nuclear genomes. This has major implications for designing typing markers for hospital acquired infections, a severe problem in intensive care units.For more information on Marcelo R. S. Briones. Please visit: http://www.hhmi.org/scientists/marcelo-briones.