11-16-2018 Luigi Luca Cavalli-Sforza (1922–2018) Joaquim Fort
Luigi Luca Cavalli-Sforza passed away on August 31st, 2018. Born in Genoa (Italy) in 1922, at age 16 he begun his undergraduate studies in Medicine in Torino. Next year he continued them in Pavia, where at age 20 he begun publishing research papers on quantitative measurements of bacterial virulence. In this field he worked with his classmate Giovanni Magni, performing experiments using mice inoculated with virulent bacteria. They discovered a linear relationship between mean death time and the logarithm of dose (i.e., the number of bacteria used for inoculations), and proposed an interpretation that isolated the two factors of virulence, namely the reproduction time of the bacteria and their toxicity (which are related, respectively, to the slope and the intercept of the linear relationship) (Cavalli and Magni 1947).