Лаццаро Спалланцани: Биолог, физиолог және ғылымға қосқан үлесі

Italian priest, biologist and physiologist

Lazzaro Spallanzani (; 12 January 1729 – 11 February 1799) was an Italian Catholic priest (for which he was nicknamed Abbé Spallanzani), biologist and physiologist who made important contributions to the experimental study of bodily functions, animal reproduction, and animal echolocation. His research on biogenesis paved the way for the downfall of the theory of spontaneous generation, a prevailing idea at the time that organisms develop from inanimate matters, though the final death blow to the idea was dealt by French scientist Louis Pasteur a century later. His most important works were summed up in his book Experiencias Para Servir a La Historia de La Generación De Animales y Plantas (Experiences to Serve to the History of the Generation of Animals and Plants), published in 1786. Among his contributions were experimental demonstrations of fertilisation between ova and spermatozoa, and in vitro fertilisation.

Spallanzani was born in Scandiano in the modern province of Reggio Emilia to Gianniccolo Spallanzani and Lucia Zigliani. His father, a lawyer by profession, was not impressed with young Spallanzani who spent more time with small animals than studies. With financial support from the Vallisnieri Foundation, his father enrolled him in the Jesuit Seminary at age 15. When he was asked to join the order, he declined. Persuaded by his father and with the help of Monsignor Castelvetro, the Bishop of Reggio, he studied law at the University of Bologna, which he gave up soon and turned to science. Here, his famous kinswoman, Laura Bassi, was a professor of physics and it is to her influence that his scientific impulse has been usually attributed. With her, he studied natural philosophy and mathematics, and gave also great attention to languages, both ancient and modern, but soon abandoned them. It took him a good friend Antonio Vallisnieri Jr. to convince his father to drop law as a career and take up academics instead. In 1754, at the age of 25, soon after he was ordained he became professor of logic, metaphysics and Greek in the University of Reggio. In 1796, Spallanzani received an offer for professor at the National Museum of Natural History, France in Paris, but declined due to his age. He died from bladder cancer on 12 February 1799, in Pavia. After his death, his bladder was removed for study by his colleagues, after which it was placed on public display in a museum in Pavia, where it remains to this day. His indefatigable exertions as a traveller, his skill and good fortune as a collector, his brilliance as a teacher and expositor, and his keenness as a controversialist no doubt aid largely in accounting for Spallanzani's exceptional fame among his contemporaries; his letters account for his close relationships with many famed scholars and philosophers, like Georges Louis Leclerc, Comte de Buffon, Lavoisier, and Voltaire. Yet greater qualities were by no means lacking. His life was one of incessant eager questioning of nature on all sides, and his many and varied works all bear the stamp of a fresh and original genius, capable of stating and solving problems in all departments of science—at one time finding the true explanation of stone skipping (formerly attributed to the elasticity of water) and at another helping to lay the foundations of our modern volcanology and meteorology. Spallanzani's experiment showed that it is not an inherent feature of matter and that it can be destroyed by an hour of boiling. As the microbes did not re appear as long as the material was hermetically sealed, he proposed that microbes move through the air and that they could be killed through boiling. Needham argued that experiments destroyed the "vegetative force" that was required for spontaneous generation to occur. Spallanzani paved the way for research by Louis Pasteur, who defeated the theory of spontaneous generation almost a century later. Spallanzani showed that some animals, especially newts, can regenerate some parts of their body if injured or surgically removed.

Spallanzani is also famous for extensive experiments in 1793 on how bats could fly at night to detect objects (including prey) and avoid obstacles, where he concluded that bats do not use their eyes for navigation, but some other sense. He concluded that bats do not need vision for navigation; although he failed to find the reason. At the time other scientists were sceptical and ridiculed his findings. He was still suspicious that deafness alone was the cause of disoriented flight and that hearing was vital that he conducted some rather painful experiments such as burning and removing the external ear, and piercing through the inner ear. After these operations, he became convinced that hearing was fundamental to normal bat flight, upon which he noted:

Gibelli, V. 1971 L. Spallanzani. Pavia. Lhoste, J. 1987 Les entomologistes français. 1750–1950. INRA (Institut National de la Recherche Agronomique), Paris. Osborn, H. 1946 Fragments of Entomological History Including Some Personal Recollections of Men and Events. Columbus, Ohio, Published by the Author. Osborn, H. 1952 A Brief History of Entomology Including Time of Demosthenes and Aristotle to Modern Times with over Five Hundred Portraits. Columbus, Ohio, The Spahr & Glenn Company.