. . "Fawcett sent over 100 questionnaires to eminent people in a \"study of the principle of heredity.\" He was interested in the influence of the number of siblings, parental age, birth order and inherited traits."@en . . . "Questionnaires"@en . . . . . . . . . . . . . . "Correspondence"@en . . . . . . "Correspondence of James Waldo Fawcett"@en . . . . . .