Biography of P. G. Svetlov (1892-1976)

He was born on September 9 (August 28) in 1892, in the village Ushaki (now Tosnensky district of the Leningrad region). His father, Grigory Ivanovich Svetlov, was a master of veterinary sciences.

In 1910, Pavel Svetlov graduated from the The Imperial Nicholas Gymnasium and was awarded a silver medal. After graduation, he entered St. Petersburg University at the Department of Natural Science of the Physics and Mathematics Faculty, in a group of

biologists, where he specialized in the Department of Zoology of Invertebrates. Even then, during the student years, Svetlov had an interest in embryology. He worked at the Sevastopol and Murmansk biological stations, studied the marine fauna. At that time, he studied the structure of sea stars, which became the basis of his thesis work. After graduating from the university in 1915, he was mobilized and, after graduation from the officer's school, sent to the Caucasian Front. After the revolution, in December 1917, he was elected as an assistant to the Department of Zoology of Invertebrates of Perm University. There the first works of Svetlov appeared in print and brought him world fame as an embryologist. In 1925, upon the invitation of Academician N. V. Nasonov, P. G. Svetlov moved to Leningrad and started working at the Special Zoological Laboratory of the Academy of Sciences of the USSR. There he began a series of studies devoted to the problem of embryonic regeneration and conducted several researches (influence on the development and regeneration of the cell external factors, in particular, ionizing radiation, poisons, etc. ) that served as a prerequisite for the creation of a theory of critical periods in the development of mammals. The higher mortality rate of the male population compared to the female population during the Siege of Leningrad prompted Pavel Grigorievich to study the physiological causes of this phenomenon. In a series of studies (1943-1950) on animals and plant objects, he convincingly demonstrated that differences in the sensitivity of the sexes to starvation and various damaging effects were inherent in the properties of cells protoplasm of the male and female body.

In addition to research, P. G. Svetlov conducted teaching work; he became a professor of the Faculty of Biology of Leningrad University. Since 1944, he headed the Department of Animal Genetics and the Laboratory of Embryology. In 1946, Pavel Grigorievich was elected a Corresponding Member of Academy of Medical Sciences of the USSR.

Rich research experience in the field of experimental embryology allowed P. G Svetlov to finish and send to print the book " Fundamentals of Mechanics of Development" in 1947. However, the book was never published during the life of Pavel Grigorievich. In August 1948, the sadly famous session of the All-Union Academy of Agricultural Sciences named after V. I. Lenin was held. After that, on the initiative of Lysenko, genetics was declared a " corrupt virgin of imperialism". Then came special resolutions of the Central Committee of the CPSU and ordered to develop only “Michurin’s biology” and destroy of scientific schools associated with genetics. On August 23, 1948 the Dean of the Faculty of Biology of the University, M. E. Lobashev, Professors Yu. I. Polyansky and P. G. Svetlov were dismissed by order of the Ministry of Higher Education. At the same time, the Department of Genetics of Animals headed by P. G. Svetlov was liquidated and almost all of its employees were dismissed. The book of P. G. Svetlov, which was in print, was destroyed; the ready-made set was scattered. Most scientists, geneticists, mindful of the fate of the colleagues destroyed by the regime, had to repent of the alleged mistakes. P. G. Svetlov did not avoid this bitter fate.

At the end of the forties, P. G Svetlov worked at the All-Union Leningrad Institute of Experimental Medicine (ALIEM) and headed the Embryology Office at the Institute of Obstetrics and Gynecology of Academy of Medical Sciences of the USSR. There he, together with G. F. Korsakova undertook a series of studies on experimental embryology of mammals.

In 1956, P. G. Svetlov headed the reconstructed laboratory of embryology ALIEM, where he continued experiments on the influence of a number of environmental factors on the development of animal embryos. The encyclopedic knowledge in various fields of biology and the experimenter's talent enabled him to make a series of large generalizations. The most important of them all is the theory of critical periods of development, which has general biological and medical significance.

This theory was finally formulated by Svetlov in the walls of the ALIEM in 1960. This theory was based on a huge amount of information accumulated by experimental embryology on the problem of reactions of a developing organism to external influences, and meaningful from the standpoint of modern genetics, cytology, biochemistry and physiology of reactive processes.

Through his experimental studies and interpretation of critical periods of development, P. G. Svetlov gave an embryological justification for the need to preserve the early period of the human uterine life (1961) and came to an almost important conclusion about the need to revise the principles of the protection of pregnancy. In 1968, Pavel Grigorievich was awarded the title of Laureate of the State Prize for the cycle of these studies.

Professor Svetlov devoted much effort and attention to the education of young scientists, dealt with issues of popularization and the history of science, wrote articles for the Great Medical Encyclopedia. The breadth of scientific and philosophical views of Professor Svetlov can be judged from the published correspondence of Pavel Grigorievich and his friend, the outstanding scientist and thinker A. A. Lyubishev, in which they conducted philosophical debates on the themes of being. According to contemporaries, a major scientist in the field of comparative and experimental embryology, Pavel Grigorievich Svetlov was a man of remarkable erudition, upbringing and spiritual purity. He was the true representative of the Russian intellectuals. Probably, many of these qualities, in any case, the knowledge of the Greek language and the history of the ancient world, he acquired through the classical education in the Imperial Nicholas Gymnasium.

Perhaps the fact or P. G. Svetlov`s advice, but the group of A. I. Nikitin (the Laboratory of IVF in the Research Institute of Obstetrics and Gynecology and Reproductology named after D. O. Ott, Leningrad) did not get acquainted with the works from Simferopol when they began to study the process of fertilization of the human oocyte in vitro in the early 70's. (It is very strange that a prominent embryologist did not consider innovative researches of Crimean scientists). In the conversation with V. Litvinov, Professor E. M. Kitaev (Obstetrician-gynecologist, employee of the IVF laboratory at the Research Institute of Obstetrics and Gynecology and Reproductology named after D. I. Ott, was in the group of A. I. Nikitin, Leningrad) said: “P. G. Svetlov did not recommended to explore researches from Simferopol… It is necessary to base and draw conclusions on our own research”. It is unfortunate that in 1996-1997, when meetings with the scientist were held, we did not ask questions that could clarify many details, such as: transfer of embryos, conclusions reported at the All-Union Congress of anatomists, embryologists, histologists (1966).

At the same time, Knorre Aleksey Georgievich (Photo № 10) highly appreciated the scientific researches of Petrov G. N. at the Crimea. A. G. Knorre was a prominent biologist, evolutionary morphologist, professor, Corresponding Member of Academy of Medical Sciences of the USSR, editor of the journal " Archive of Anatomy, Histology and Embryology". He " sent a letter to us to continue our work, because these studies have a unique significance. " This fact contributed to the continuation of G. N. Petrov’s scientific work.