The birth of chronobiology: Julien Joseph Virey 1814

Julien-Joseph Virey (1775-1846) held the position of pharmacist-in-chief at the Val-de-Grace, a military hospital. He was an innovative pharmacist, na turalist, anthropologist, and philosopher and a prolific author. His writin gs encompassed a wide range of topics, although many of his ideas were some times harshly questioned. Interest in Virey's work today stems from renewed appreciation of his doctoral thesis in medicine, which was completed in 18 14 in Paris and was the first devoted to biological rhythms. Virey envision ed biological rhythms to be innate in origin and controlled by living clock s entrained by periodic environmental changes, such as the day night altern ation in light and darkness. He also reported that the effects of drugs var y according to their administration time. But, above all, he collected and published quantified time series that demonstrated human circadian and annu al mortality rhythms. Statistical analysis of Virey's data using modern tim e series methods confirms his deduction that human mortality exhibits rhyth micity. Comparison of his findings with those derived from analyses of more recent human mortality time series shows the characteristics of these rhyt hms have changed little since 1807 despite differences in environmental con ditions. Virey deserves credit for establishing the field of chronobiology based on his insights and writings.