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Luigi Luca Cavalli-Sforza (1922–2018)
- Human Biology
- Wayne State University Press
- Early Views
- 10.1353/hub.2017.0049
- Article
- Additional Information
1 Complex Systems Laboratory, University of Girona, Catalonia, Spain. 2 Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Catalonia, Spain. *Correspondence to: Joaquim Fort, Complex Systems Laboratory, University of Girona, Building (edifijici) P2, 2nd floor, Offfijice 216, Avda. Maria Aurelia Capmany 61, 17003 Girona, Catalonia, Spain. E-mail: joaquim.fort@udg.edu. Human Biology, Spring 2018, v. 90, no. 2. doi: 10.13110/humanbiology.90.2.01. Copyright © 2018 Wayne State University Press, Detroit, Michigan 48201 in memoriam Luigi Luca Cavalli-Sforza (1922–2018) Joaquim Fort1,2 * Luigi Luca Cavalli-Sforza passed away on 31 August 2018. Born in Genoa, Italy, in 1922, at age 16 he began his undergraduate studies in medicine in Torino and continued them the next year in Pavia. At age 20 he began publishing research papers on quantitative measurements of bacterial virulence. In this fijield he worked with his classmate Giovanni Magni, performing experimentsusingmiceinoculatedwithvirulentbacteria . 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: 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). In1944,Cavalli-Sforzafijinishedhisundergraduate studies and had already published eleven research papers. These were followed by six papers the following year, including his fijirst one coauthored with Adriano Buzzati-Traverso (BuzzatiTraverso and Cavalli 1945), who was his teacher in a genetics course in 1942. Cavalli-Sforza had met Buzzati-Traverso after three years of looking for a mentor who could teach him how to become a researcher(Cavalli-SforzaandCavalli-Sforza2005). Buzzati-Traverso’s complete dedication to science deeply impressed Cavalli-Sforza, who considered him one of the people who had a major influence on his life. Their fijirst joint research papers dealt with population genetics of Drosophila (BuzzatiTraverso and Cavalli 1945) and planktonic organisms in lakes (Baldi et al. 1945). At the end of WorldWar II no jobs were offfered at Italian universities, and Cavalli-Sforza worked as a doctor in a hospital during 1944–1945. Discouraged by the lack of drugs to help patients, he found a job at the Istituto Sieroterapico Milanese, a pharmaceutical institute in Milan (Cavalli-Sforza and Cavalli-Sforza 2005). There, during the morningsheextractedbloodfrompatientsanddidother works, and in the afternoons he managed to performresearchexperimentsthatledtopublications on quantitative analyses of bacterial resistance to X-rays and other mutagens (Buzzati-Traverso et al. FIGURE 1. Luigi Luca CavalliSforza (le) and the author, at Cavalli-Sforza’s home in Milano, March 2016. 000 ■ Fort 1948).Healsofoundtimetolearnmathematicsand statistics on his own. Without prospects of improving his professional situation, he felt a strong desire to fijind a full-time research position in England or the United States. Only in 1948 he was awarded a grant to spend some months in England, in the lab of Kenneth Mather, a former student of Ronald A. Fisher. The latter was one of the most important evolutionary geneticists at the time and had also donemajorfoundationalworkinmodernstatistics. Fisher had been trying to test his mathematical theory of DNA crossing over using experiments with mice, but he wanted to do it with bacteria because Joshua Lederberg had shown in 1946 that bacteria recombine, and they have a much shorter generation time than mice. Thus, Fisher was lookingforaresearcherwithexperienceinbacteriology . Mather presumably recommended Cavalli-Sforza to Fisher, who offfered Cavalli-Sforza a position in Cambridge during a conference in 1948 (CavalliSforza 1990; Edwards 2009). Cavalli-Sforza accepted Fisher’s offfer, and that same year he moved to Cambridge and built a bacteriology laboratory from scratch in less than four months (Cavalli-Sforza and Cavalli-Sforza 2005). Although unexpected complications made itimpossibletotesttheFishermathematicaltheory of DNAcrossingoverusingbacteria(Cavalli-Sforza 1990), Cavalli-Sforza obtained new results during his stay in Cambridge (his publications during this period included two papers in Nature). Lederberg sent him the E. coli strain that he had used for his recombination experiments, and Cavalli-Sforza succeeded in isolating a mutant that exhibited an enormously higher frequency of recombination (Cavalli-Sforza 1950). He attained this success by repeating his previous experiments on E. coli mutantsresistanttoagents ,butnowusingLederberg’s...