Sporulation environment drives phenotypic variation in the pathogen Aspergillus fumigatus

Aspergillus fumigatus causes more than 300,000 life-threatening infections annually and is widespread across varied environments with a single colony producing thousands of conidia, genetically-identical dormant spores. Conidia are easily wind-dispersed to new environments where they can germinate and, if inhaled by susceptible hosts, cause disease. Using high-throughput, single-cell analysis we show that germination phenotypes vary among genetically-identical individuals and that the environment of spore production determines the degree of germination heterogeneity.